BA2076_EPT202_en_Rev4

www.messko.de MTeC- EPT202 Digital ThermometerOperating Instructions BA 2076/04/01

Messko

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MesskoTable of Contents

1 General ............................................................................................................................................................................ 5

1.1 Safety Instructions .........................................................................................................................................................................5

1.2 Appropriate use...............................................................................................................................................................................5

1.3 Notes on the Operation of the Device .....................................................................................................................................5

1.4 Confi guration ..................................................................................................................................................................................5

1.5 Features of the basic units ..........................................................................................................................................................5

2 Technical Data ................................................................................................................................................................ 7

3 Installation ...................................................................................................................................................................... 9

3.1 EPT202 for rail mounting .............................................................................................................................................................9

3.2 EPT202 as 19 slide-in unit (42HP) ...........................................................................................................................................9

3.3 EPT202 for panal mounting .........................................................................................................................................................9

3.4 EPT202 as 19 slide-in unit (84HP) .........................................................................................................................................10

4 Electrical connection .................................................................................................................................................... 11

4.1 Device earthing ............................................................................................................................................................................. 11

4.2 Supply voltage ............................................................................................................................................................................... 11

4.3 Sensor inputs ................................................................................................................................................................................. 11

4.4 CT input (secondary) ....................................................................................................................................................................12

4.5 Analog outputs .............................................................................................................................................................................12

4.6 Digital interfaces ..........................................................................................................................................................................13

4.7 Relay contacts for controlling cooling stages .....................................................................................................................13

4.8 Relay contacts for alarm/trip messages ................................................................................................................................15

4.9 Error contact ..................................................................................................................................................................................15

5 Functional description .................................................................................................................................................16

5.1 Sensor inputs .................................................................................................................................................................................16

5.2 Deactivating the winding temperature ..................................................................................................................................16

5.3 Winding temperature calculation (hotspot temperature) ................................................................................................16

5.4 Winding parameters ....................................................................................................................................................................17

5.5 Lifetime consumption calculation ...........................................................................................................................................17

5.6 Relay contacts ...............................................................................................................................................................................17

5.7 Cooling system control ...............................................................................................................................................................18

5.8 Load cycle mode ...........................................................................................................................................................................22

5.9 Device self-monitoring ...............................................................................................................................................................23

5.10 Analog outputs .............................................................................................................................................................................23

5.11 Data logging ..................................................................................................................................................................................23

6 Operation ......................................................................................................................................................................24

6.1 Front panel .....................................................................................................................................................................................24

6.2 Menu control .................................................................................................................................................................................16

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7 Display and parametrierung ........................................................................................................................................267.1 Input and output confi guration ...............................................................................................................................................26

7.2 Cooling stage-specifi c parameters ..........................................................................................................................................27

7.3 Switching contacts for cooling system control ...................................................................................................................28

7.4 Switching contacts for alarm messages ................................................................................................................................29

7.5 Lifetime consumption calculation ...........................................................................................................................................30

7.6 Menu ...........................................................................................................................................................30

7.7 Menu ..............................................................................................................................................................31

7.8 Operator data menu ....................................................................................................................................................................31

7.9 Manufacturer data menu ...........................................................................................................................................................31

8 Visualization software ..................................................................................................................................................328.1 Installation of the visualization software for the EPT202 ................................................................................................32

8.2 Uninstalling the visualization software .................................................................................................................................33

8.3 Installing the USB driver ............................................................................................................................................................34

8.4 Uninstalling the USB driver .......................................................................................................................................................36

8.5 Software structure .......................................................................................................................................................................37

8.6 EPT202-Monitor ...........................................................................................................................................................................38

8.7 Menubar ..........................................................................................................................................................................................38

8.8 menu ...........................................................................................................................................................................39

8.9 menu ......................................................................................................................................................................41

8.10 Print wizard ....................................................................................................................................................................................42

8.11 menu ...............................................................................................................................................................43

8.12 menu .................................................................................................................................................................49

8.13 menu ...........................................................................................................................................................................51

8.14 EasySet function ...........................................................................................................................................................................56

8.15 menu ...................................................................................................................................................................57

9 Appendix .......................................................................................................................................................................58

9.1 Dimensional drawing EPT202 for rail mounting .................................................................................................................58

9.2 Dimensional drawing EPT202 as 19 rack (42HP)...............................................................................................................59

9.3 Dimensional drawing EPT202 for panel mounting .............................................................................................................60

9.4 Dimensional drawing EPT202 as 19 rack (84HP)...............................................................................................................61

9.5 Terminal diagram EPT202 for rail mounting ........................................................................................................................62

9.6 Terminal diagram EPT202 for panel mounting and 19 rack ...........................................................................................63

9.7 Circuit diagram 4...20 mA sensor connection ......................................................................................................................64

9.8 Circuit diagram Pt100 sensor connection, 3 wire...............................................................................................................65

9.9 Circuit diagram for Indicating instrument EI100/160 .......................................................................................................66

9.10 Wiring diagram for digital indicator .......................................................................................................................................67

Please keep this manual for future reference!

HINWEIS

Data contained herein may differ in details from the equip-ment delivered.

We reserve the right to make alterations without notice.

Table of Contents

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Messko1 General

1 General

1.1 Safety Instructions

All personnel involved in installation, commissioning, operation, maintenance or repair of the equipment must be suitably qualifi ed and strictly observe these operating instructions.Improper operation or misuse can lead to serious or fatal injury, damage to the equipment and property of the operator and a reduction in the effi ciency of the equipment.

Safety instructions in this manual are presented in three diffe-rent forms to emphasize important information.

1.2 Appropriate use

In conjunction with a temperature sensor the EPT202 device from the MTeC device series indicates the oil and winding temperature of oil-insulated transformers, reactors or on-load tap-changers. The device can be used to control individual cooling stages as a function of load and temperature and to switch off the whole transformer in the event of an emergency. Before commissioning the device be sure to read and observe the application limit values specifi ed on the nameplate and in the operating instructions.

1.3 Notes on the Operation of the Device

User adherence to national accident prevention regulations is mandatory.

It is also pointed out that work on active ports (i. e., parts which are hazardous to touch) is only permitted when these parts are potential free or are protected against direct touch.

WARNING

This information indicates particular danger to life and health. Disregarding such warnings can lead to serious or fatal injury.

CAUTION

This information indicates particular danger to the equip-ment or other property of the operator, risk of serious or fatal injury.

NOTE

These notes provide important information on a certain topic.

National regulations pertaining to electrical installation must be observed. To ensure correct operation, it is essential to connect the protective conductor (PE).

1.4 Confi guration

The device is available in four versions:

- As a compact device in an aluminum housing for mounting on a mounting rail according to EN 60 715 TH 35-7.5 and TH 35-15

- As a 19 slide-in unit (3U, 42HP, depth 176 mm) for installation in a 19 cabinet system

- As a device for panel mounting with a 236 x 142 mm panel cut-out

- As a 19 slide-in unit (3U, 84HP, depth 176 mm) for installation in a 19 cabinet system.

Plug connectors according to DIN 41 612 are used for the elec-trical connection.

NOTE

When using the additional modules EPT202OL, EPT202CT or EPT202OL/CT, please refer to the operating instructions BA 2078.

CAUTION

Make sure that all power supplies leading to the digital thermometer are disconnected at the switchgear cubicle before doing impulse voltage testing or any other kind of applied voltage testing to the transformer.

1.5 Features of the basic unit

The basic unit is used to visualise 1 oil temperature and 1 winding temperature of an oil-insulated transformer or similar device on an LCD display. To this end a temperature sensor with Pt100 or 4...20 mA output must be connected to the device for measuring the top oil temperature in the transfor-mer. The minimum and maximum values of the oil and winding temperature and the maximum value of the load current are recorded and can be retrieved later. Two analog outputs with freely programmable output signals and an RS485 interface are available for remote display of the temperature values. Through the data logging function the temperature-specifi c data are stored in the device at regular intervals and can be retrieved at any time. The thermal image of the transformer is simulated according to IEC 60076-7 or ANSI IEEE Std. C 57.91. To this end the CT current refl ecting the transformer load must be connected to the device. Transformer- and cooling stage-specifi c parametering can be carried out via the keys on the front or optionally available visualization software. The visua-lization software contains an Easy-Set function for paramete-

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1 General

Another special feature is calculation of life-cycle consumption according to IEC or ANSI standard.

A temperature sensor for logging the ambient temperature can be connected via the 4-20 mA sensor input. In this case a Pt100 sensor must be used for detecting the top oil tempera-ture.

ring according to IEC standard. A total of 6 relays can be used for controlling cooling stages or issuing messages such as oil temperature warning or trip. Additional functions are available for the cooling stage contacts:

Alternating fan operation ensures that the units for similar cooling stages (e. g. fans for ONAF-1 and ONAF-2) are used uniformly over time.

The periodic cooling stage activation function can be used to briefl y switch on cooling units that only operate occasio-nally.

The load-dependent cooling stage activation function acti-vates the cooling stages in the event of a rapid load increase. This is useful for machine transformers with high loads or in the event of failure of a transformer operating in parallel mode.

The switching point, the hysteresis and the delay time of the individual relays are freely adjustable. The relay contacts can be activated and deactivated via the oil or winding tempera-ture.

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2 Technical Data

Protective housing

Rail mounting: Rail mounting: Aluminum housing, can be snapped on for carrying rail in accordance with DIN EN 60715 TH 35-7.5 and TH 35-15, protection rating: IP 00 in accordance with IEC 60529, weight: approx. 1.2 kg

19 slide-in unit 42HP: 19 slide-in unit 42HP: 19 rack in accordance with DIN 41494, part 5, 223 x 133 x 178 mm (W x H x D) for installation in 19 cabinet system, protection rating: IP 00 in accordance with IEC 60529, weight: approx. 1.5 kg

Panel mounting: Panel mounting: Aluminum housing, 270 x 200 x 133 mm (W x H x D) for panel mounting with a 236 x 142 mm panel cut-out, protection rating: IP 00 in accordance with IEC 60529, weight: approx. 1.5 kg

19 slide-in unit 84HP: 19 slide-in unit 84HP: 19 rack in accordance with DIN 41494, part 5, 483 x 133 x 178 mm (W x H x D), protection rating: IP 00 in accordance with IEC 60529, weight: approx. 2.5 kg

Temperature ranges

Operation: -25C to +70C

Storage: -30C to +85C

Operator elements, indication, terminals

Operator elements: 5 function buttons with perceptible pressure point

Indication: Monochrome display, black letters on white backlight or alternatively white letters on blue backlight, 128 x 64 pixels

Status LEDs: 1 LED, green, for POWER operational indication1 LED, yellow, for ALARM switching contact1 LED, red, for TRIP switching contact1 LED, red, for ERROR switching contact4 LEDs, yellow, for switching contacts S1, S2, S3 and S4

Terminals: Safety screw terminals, for rigid braided leads: 0.2 - 2.5 mm2, AWG 24 - 12,fl exible braided leads (with core end sleeves): 0.2 - 2.5 mm2, AWG 24 - 12

Inputs

Supply voltage: 80 to 265 V AC, 40 to 400 Hz80 to 353 V DCoptional: 20-72 V DCPower consumption: Max. of 10 VA or 10 W

Temperature sensor: Pt100 signal in accordance with IEC 751 in 2 or 3-conductor technology or 4 to 20 mA signal (active or passive), standard measuring range: -20 C to +140 C (others on request)

Measuring converters can be provided for other input signals e. g. 0 to 1 mA or 0 to 10 V.

Optional: The 4-20mA input can be used to record the ambient temperature (active or passive signal), the standard measuring range is -40 to +120 C.

Current transformer: 0,5 to 5 A CT rated current

Continuous load capacity: 10 A for 8 hours

Short-time current: 500 A for 1 second

Optional: Design including a split core current transformer for cable diameters up to max. 10

2 Technical Data

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2 Technical Data

Outputs

Analog outputs: 1 oil temperature, standard temperature range: -20 C to +140 C1 winding temperature, standard temperature range: 0 C to +160 C

Both analog outputs can be set as desired to: 4 to 20 mA (error signal < 3.6 mA)4 to 20 mA (error signal > 22 mA)0 to 20 mA (error signal > 22 mA)Free adjustable mA signal (max. 0-20mA)Free adjustable V signal (max. 0-10V)

Service interface: 1 USB, socket type B

Bus interface: 1 RS485 on screw terminals

Relays: 6 c/o contacts for switching points and alarm messages

1 c/o contact for device self diagnostic function

Contact capacity: S1 to S4: AC: 250 V / 12 A, 120 V / 12 A; DC: 250 V / 0,3 A, 120 V / 0,4 A, 24 V / 12 AS5, S6 and Error contact: AC: 250 V / 5 A, 120 V / 5 A; DC: 250 V / 0,3 A, 120 V / 0,4 A, 24 V / 5 A

Tests

Electrical safety: Protection class 1 in accordance with IEC 60536Protection rating IP00 in accordance with IEC 60529Degree of soiling 2 in accordance with IEC report 664-1Overvoltage category III in accordance with IEC report 664-1

Electromagnetic IEC 61000-4-2 Interference immunity against electrostatic discharge with 6/8 kVcompatibility: IEC 61000-4-3 Interference immunity against HF fi elds with 10 V / m, 80 to 1000 MHz IEC 61000-4-4 Interference immunity against bursts with 2 kV IEC 61000-4-5 Interference immunity against surges with 2 kV IEC 61000-4-6 Interference immunity against HF on lines with 10 V, 150 kHz to 80 MHz IEC 61000-4-8 Interference immunity against magnetic fi elds with 30 A/m, 50 Hz, continuous IEC 61000-4-11 Interference immunity against voltage drops with AC supply: 30 % / 0.5 period 60 % / 5 periods; with DC supply 100 % / 10 ms and 60 % / 100 ms EN 61000-6-2 CE conformity EN 61000-6-4 CE conformity

Temperature and IEC 60068-2-1 Dry cold, -25 C / 20 hours climate resistance: IEC 60068-2-2 Dry heat, +70 C / 16 hours IEC 60068-2-2 Dry heat, +70 C / 16 hours IEC 60068-2-3 Moist heat, constant, +40 C/93 % / 2 days, no moisture condensation IEC 60068-2-30 Moist heat, cyclic (12 x 12 hours) + 55 C / 93 % / 6 cycles

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3 Installation

3.1 EPT202 for rail mounting

The EPT202 (see Fig. 1) is designed for installation on a mounting rail according to EN 60715 TH 35-7.5 or TH35-15. To install the device use the assembly bracket to position it on the mounting rail and push it upwards until it snaps onto the mounting rail. The dimensions are specifi ed in the Annex (Section 9.1).

3.2 EPT202 as 19 slide-in unit (42HP)

The standardized EPT202 slide-in unit is designed for instal-lation in a 19 cabinet system. Slide the unit into the cabinet system and fasten it via the holes at the front (see Annex, Section 9.2).

3.3 EPT202 for panel mounting

A panel cut-out must be provided in the control cabinet for installation of the EPT202 (dimensions see Annex, Section 9.3). Slide the device into the cut-out and fasten it via the holes at the front.

Fig. 3Fig. 2

CAUTION

Installation, electrical connection and commissioning of the device may only be carried out by qualifi ed, skilled personnel and only in accordance with these operating instructions. It is the responsibility of the user to make sure that the EPT202 is used for the specifi ed application only. For safety reasons any unauthorized work, i.e. installation, modifi cation, electrical connection or commissioning of the equipment is forbidden without fi rst consulting Messko.

Fig. 1

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3.4 EPT202 as 19 slide-in unit (84HP)

A double-width 19 slide-in unit (84HP) is available for in-stallation in the motor drive unit ED from MR or other control cabinet applications. The unit is installed in the same way as the standard 19 unit (see 3.2). The dimensions are specifi ed in the Annex.

3 Installation

Fig. 4

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4 Electrical connection

Connect the EPT202 according to the device-specifi c wiring diagrams shown in the Annex (see 9.5-9.7). The individual connections are explained in more detail below.

4.1 Device earthing

To create safe equipotential bonding between the casing and electronic components and to discharge fault currents that may be generated through EMC infl uences the device should be earthed via the designed ground screw on the side. The housing potential must be equal to the potential of the grounding terminal (terminal 21 in the rail mounting version or terminal 43 in the 19 version).

WARNING

Ensure that the EPT202 is connected and earthed with due care. Danger to life! Do not switch on the supply voltage before the electrical connection was completed.

NOTE

The EPT202 was developed in compliance with the relevant EMC standards. The following instructions must be followed to ensure that the EMC characteristics are maintained:

Follow the separate installation instructions for the device Ensure that the EPT202 is earthed properly via the earth

terminal. Be sure to use only shielded cables for the data and signal

link between the EPT202 and other equipment. Earth the shield at the designed terminals.

Fig. 5

Rail mounting

Fig. 6

19-/panel mounting


4.2 Supply voltage

The EPT202 has a wide-range power supply unit for supply voltages between 80-265 VAC, 40-400 Hz or 80-353 VDC. Optionally a power supply unit for 20-72 VDC is available. Connect the supply voltage at the corresponding terminals.

19 panel mounting

4.3 Sensor inputs

A temperature sensor for determining the top oil temperature must be connected to the EPT202. A Pt100 sensor or a sensor with 4-20 mA output can be connected. If the ambient tempe-rature is to be logged in addition to the top oil temperature, a Pt100 sensor should be used for the top oil temperature and a 4-20 mA sensor for the ambient temperature.

4.3.1 3-wire Pt100 signal (RTD)

The Pt100 sensor should be connected in 3-wire mode (2 mea-suring lines and 1 compensating line). The 3 stranded wires should be identical (same length and cross-section). Otherwise deviations may occur through incorrect compensation of the line resistances. To connect a sensor in 2-wire mode the termi-nal for the compensating line (terminal 9 for the mounting rail version, terminal 12 for 19/panel mounting) should be short-circuited with the measuring line. Measurement errors arising from lack of line resistance compensation can be corrected with the zero point correction function.

Rail mounting

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Rail mounting 19/panel mounting

4.3.2 Input I1 for passive 4 to 20 mA sensor

Input I1 has an internal voltage source for supplying a passive 4-20 mA sensor via the measuring lines (e.g. poin-ter thermometer MT-ST160SK/TT or temperature sensor Kombi/TT). Please ensure that the connected sensor sup-ports this voltage supply method. The voltage source supplies 24 VDC 15 %.

4.3.3 Input I2 for aktive 4 to 20 mA sensor

An active 4-20 mA sensor (e. g. tempe-rature sensor TT-PWM60) with external supply can be connected to input I2.

4.4 CT input (secondary)

The CT input is designed for a rated current (at rated transfor-mer load) of 0.5 A - 5 A. Please ensure that this matches the characteristic data of the CT transformer.

The maximum input current is 8 A. While higher value will not destroy the input, the value will no longer be detected.

WARNING

Caution: high voltage with open transformer terminals and connected secondary current transformer (CT). The CT transformer must be earthed single-sided.


4.5 Analog outputs

The EPT202 has analog outputs for the oil temperature and the winding temperature for remote data transmission to control room, for example. Please specify the measuring ranges of the analog outputs with your order. The standard ranges are -20 - +140 C for the oil temperature and 0 - +160 C for the winding temperature. The output signals of the analog outputs are freely parameterizable within the following ranges: DC voltage signal: 0 - 1.0 V to 0 - 10.0 V DC signal: 0 - 1.0mA to 0 - 20.0mA

In addition 3 standard signals (with fault signal) are available: 4 - 20 mA (fault signal < 3.6 mA) 4 - 20 mA (fault signal > 22 mA) 0 - 20 mA (fault signal > 22 mA)

The fault signal is connected to the analog outputs if the oil temperature sensor is detected as faulty as a result of a cable break or a short circuit. The connected display will show a mini-mum (3.6 mA) or maximum (22 mA) value to indicate the fault. This function is not available for the freely parameterizable outputs, where the output is 0 mA or 0 V.

If an analog output is not used it must be looped through with a short-circuiting jumper. Otherwise an open analog output will be detected in the device and reported as a fault. If the analog output is operated as a DC voltage signal this type of fault detection is not possible.

If the analog outputs are parameterized as DC voltage outputs, a maximum burden resistance (total resistance of the lines and connected devices) of 750 must not be exceeded.

If the analog outputs are parameterized as DC current outputs, the output burden resistance must be greater than 1 k. The electronic analysis equipment and the display should have high input impedance.

The measuring ranges of the EPT202 and the connected devices (electronic analysis system, display, ...) must match. Otherwise incorrect values will be displayed.

Example:EPT202 data:Measuring rangeAnalog output for oil temperature: -20 - +140COutput signal: 4 - 20 mA 4 mA corresponds to -20 C

20 mA corresponds to +140 C

Data display:Input signal for the connected display: 4 - 20 mAIndicating range of the connected display: -20 - +140 C

Rail mounting

19/panel mounting


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RS485 interface:

A permanent communication link between the visualization software and the EPT202 can be established via the RS485 in-terface. The RS485 interface is confi gured as a 2-wire system. In addition to the two signal cables the GND potential should be included in the loop. The maximum connection length is limited to 500 m in accordance with ISO 8482. Low-capa-citance/attenuation, twisted pair cables should be used.

The signal cables should be terminated with 120 resistors at both ends (see Fig. 7). According to ISO 8482 an interface card or interface converter with galvanic isolation must be used in order to avoid potential differences that may arise between the individual system ground connections due to the large trans-mission lengths. Up to 32 devices can be connected to the bus system.

Fig. 7

4.6 Digital interfaces

USB interface:

The EPT202 features a USB port at the front. For connection to the EPT202 a USB cable with a USB type B connector at one end (typical printer cable) is required.

This interface is designed for parametering the device and data retrieval with a PC or laptop, but not for a permanent data link. When connecting a PC or laptop ensure that the supply voltage of the EPT202 and the PC/laptop have the same potential (use socket in control cabinet). Operate a laptop in battery mode if possible. Potential differences may destroy the equipment.

Rail mounting

19/panel mounting

4.7 Relay contacts for controlling cooling stages

Relay contacts S1 to S4 can be used to control up to 4 additional cooling stages. The number of cooling stages can be parameterized, thereby defi ning the number of relay contacts used for controlling the cooling stages. Relay contacts that are not used for controlling cooling stages can be used as alarm or trip contacts. The switching characteristic of the relay contacts used for controlling cooling stages differs from the switching characteristic of alarm and trip contacts. Therefore please ensure correct parametering of the relay contacts and cooling stages. Further information on switching contact parametering can be found in the functional description in Section 5.

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When connecting the relay contacts for controlling cooling stages please note the switching characteristic. Two following settings are possible:

Fail safe mode:

This mode ensures that the cooling stages are switched on if the supply voltage for the EPT202, the EPT202 itself or the oil temperature sensor fails, in which case the current oil or winding temperature is unknown.

The cooling stages or their contactors must be connected at the NC contacts of the corresponding change-over contact. See the following example of a motor (fan) connected to relay contact S1 in the top hat rail version of the EPT202.

Original stateEPT202 without motor on supply voltage (cooling stage on)EPT202 faulty

Operating state,switching point motor off not exceeded, (cooling stage off)EPT202 OK

Operating state,switching point motor onexceeded, (cooling stage on)EPT202 OK

Oil temperature motor onsensor faulty (cooling stage on)

Standard mode:

In standard mode the cooling stages are only activated if an oil temperature sensor fails, but not in the event of failure of the supply voltage or the EPT202 itself. The cooling stages or their contactors must be connected at the NO contact of the corres-ponding change-over contact. See the following example of a motor (fan) connected to relay contact S1 in the top hat rail version of the EPT202.

Original stateEPT202 without motor off supply voltage (cooling stage off)EPT202 faulty

Operating state,switching point motor off not exceeded, (cooling stage off)EPT202 OK

Operating state,switching point motor onexceeded, (cooling stage on)EPT202 OK

Oil temperature motor onsensor faulty (cooling stage on)

Rail mounting

19/panel mounting

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4.9 Error contact

The internal self-monitoring function issues an error message via the error contact if a fault is detected in the device. The switching characteristic can be parameterized by the user:

Fail safe mode:

In this mode an error message is issued if the supply voltage for the EPT202 fails or the EPT202 is faulty.

The wiring must be connected to the NC contact of the cor-responding change-over contact. See the following example of a signaling lamp connected to error relay contact in the top hat rail version of the EPT202.

Original stateEPT202 without lamp on supply (error message)voltage

Operating state, lamp offno fault (no error message)

Fault:input sensorfaulty, analog output lamp onopen (error message)internal fault,supply voltagefault


Standard mode:

In this mode no error message is issued if the supply voltage for the EPT202 fails or the EPT202 is faulty. This setting can be used in confi gurations with frequent switching of the EPT202 supply voltage between internal supply and mains supply or internal supply and battery backup. In fail safe mode an error message would be issued in this case.

The wiring must be connected to the NO contact of the cor-responding change-over contact. See the following example of a signaling lamp connected to error relay contact in the top hat rail version of the EPT202.

Original stateEPT202 without lamp off supply (no error message)voltage

Operating state, lamp offno fault (no error message)

Fault:Input sensorfaulty, analog output lamp onopen (error message)internal fault,supply voltagefault

Rail mounting 19-/panel mounting


4.8 Relay contacts for alarm/trip messages

The ALARM and TRIP relay contacts and relay contacts S1 - S4 (when not used for controlling cooling stages) can be used for overtemperature messages, alarm messages or also signals for transformer tripping.

In contrast to the relays for controlling the cooling stages these relays only respond if the switch point is exceeded, and not in the event of a device or sensor fault or failure of the supply voltage.

The wiring must be connected to the NO contact of the cor-responding change-over contact.

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5 Functional description


The EPT202 is used for temperature monitoring and cooling stage control at transformers or similar equipment.

The device can be used to record the oil temperature from which the winding temperature can be calculated. Based on the temperatures the EPT202 can control fans or other cooling units via relay contacts. The individual functions are explained in more detail below.

5.1 Sensor inputs

Suitable input sensors for the top oil temperature are Pt100 sensors or sensors with active or passive (supply voltage via the measuring lines) 4-20 mA output signal. The sensor type can be customized, although the input ranges have to be factory-set (standard input range -20 C +140 C). The temperature range of the input sensor must match the input range of the EPT202 (see nameplates).

Otherwise the oil and winding temperature display is incorrect.

The EPT202 can optionally be used to log the ambient tem-perature. In this case a sensor with 4-20 mA output must be connected as input sensor for the ambient temperature and a Pt100 sensor as input sensor for the top oil temperature.

The two sensor inputs for Pt100 and 4-20 mA are monitored via the device self-monitoring function (see Section 5.9). In the event of a short circuit or cable break/signal disruption an error message is issued via the ERROR relay.

5.2 Deactivating the winding temperature

The winding temperature function can be deactivated in the EPT202 if only the oil temperature is to be logged as a basis for cooling system control, for example. If this function is deac-tivated the following calculations and algorithms are automa-tically disabled:

CT input, load current and load factor calculation Winding temperature calculation MIN/MAX winding temperature logging Analog winding temperature output Lifetime consumption calculation Load-dependent cooling stage activation

5.3 Winding temperature calculation (hotspot temperature)

The thermal image (hotspot temperature) is calculated accor-ding to IEC 60076-7 or ANSI IEEE standard C57.91 based on the oil temperature and the actual load current. The formulas for calculating the hotspot temperature are shown below. Further information can be found in the corresponding stan-dards.

Calculation according to IEC 60076-7

Calculation according to IEC 60076-7

with : Hotspot temperature at time t

: Current top oil temperature

: Hotspot factor (only for IEC standard)

: Gradient between mean winding temperature and mean oil temperature at rated current (only for IEC standard)

: Gradient between hotspot temperature and top oil temperature at rated current (only for ANSI standard)

: Load factor (actual/rated current)

: Winding exponent (only for IEC standard)

: Exponent for calculating the current hotspot temperature (only for ANSI standard)

: Transformer oil time constant

The current top oil temperature is logged with a Pt100 sensor or a temperature sensor with 4-20 mA output and fed into the EPT202.

The CT current transformer is connected to the EPT202 for mapping the actual load current.

The other factors and parameters described above have to be parameterized in the EPT202.

For parametering according to ANSI standard the hotspot factor should be set to 1.0 and the winding exponent to 2 x m (i. e. for m = 0.8 a factor of 1.6 should be used).

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5.4 Winding parameters

The EPT202 processes two different types of winding parame-ters.

The parameters hotspot factor and CT ratio are generally valid for the transformer and do not change when individual cooling stages are switched on or off.

The parameters gradient, rated CT current, winding exponent and time constant may change when cooling stages are swit-ched on or off. For example, the rated CT current may increase due to the fact that a transformer can handle a higher load as a result of increased cooling capacity when a cooling stage is switched on. These parameters can be set in the EPT202 for up to 5 cooling stages.

5.5 Lifetime consumption calculation

The lifetime consumption calculation can be confi gured based on two different algorithms (ANSI or IEC standard) or deac-tivated. Please refer to the relevant standards for the lifetime consumption calculation formulas.

Both algorithms are a function of the hotspot temperature.

The calculation can only provide a sensible value if the winding parameters are set correctly.

Both algorithms provide the lifetime consumption in percent based on the expected service life. To this end the expected service life must be parameterized.

The expected service life for the insulation system of a trans-former winding is a function of the materials and the design.

This value can be requested from the transformer manufac-turer.

5.6 Relay contacts

The EPT202 has 7 relay contacts in total with the following functions:

ID Function Alternative function

S1 cooling system control warning message




ALARM warning message

TRIP warning message

ERROR device self-monitoring

In the EPT202 the number of cooling systems (max. 4 in addition to natural cooling) can be parameterized. Relay contacts S1-S4 (if not used for controlling a cooling system) can be used as relay contacts for warning messages (e. g. alarm or trip message). The following confi guration would be possible, for example:

ID Function Description

S1 cooling system control ONAF-1 via winding temperature

S2 cooling system control ONAF-2 via winding temperature

S3 warning message alarm via oil temperature

S4 warning message trip via oil temperature

ALARM warning message alarm via winding temperature

TRIP warning message trip via winding temperature

ERROR device self-monitoring device fault

CAUTION

The EPT202 lifetime consumption calculation is based on thermal aging of the transformer insulation according to ANSI or IEC standard. The calculated value may differ from the actual value.

The lifetime consumption only relates to the insulation system of the transformer, not the whole transformer.

18 BA 2076/04 /01

The relay contacts used for warning messages have different switching characteristics than the contacts for controlling the cooling stages. If the oil temperature sensor fails the contacts for controlling the cooling stages are activated, but not the contacts for warning messages (e. g. alarm or trip).

The relay contacts for warning messages can be activated via the oil or winding temperature. The switching point, hysteresis and delay time can be set. Unused contacts can be hidden.

5.7 Cooling system control

The individual transformer cooling stages can be controlled via relay contacts S1-S4.

The EPT202 is designed to use natural transformer cooling (usually ONAN) as the basic cooling stage (referred to as Cooling 0 in the device). This cooling stage has no cooling unit controlled by the EPT202.

In additional to the basic cooling stage up to 4 further cooling stages (Cooling 1-4) can be activated via relay contacts S1-S4.

The relays and therefore the cooling stages can be activated via different functions:

Exceedance of switch points for the oil or winding tempera-ture (this function is explained below).

Exceedance of a particular load. This function is described in section 5.7, page 20, Load-dependent cooling stage activati-on.

Via time control. This function is described in section 5.7, page 21, Periodic cooling stage activation.

Activation of the cooling stages via switch points for the oil or winding temperature:

For the individual cooling stages temperature exceedance switch points can be parameterized, e.g. switch on cooling stage ONAF when the oil temperature exceeds 60 C. The cooling stage activation can be based on the oil temperature or the winding temperature. In addition, cooling stages can be switched on permanently via the command.

The cooling stage is deactivated and switched off when the temperature value falls below the switching point minus an adjustable hysteresis. Again, switching can be controlled via the oil or the winding temperature. The fi ve possible control options are shown below:

Activation Deactivation Notes

Manual on --- cooling stage always switched on

Oil temperature Oil temperature only possible parameterization with hidden winding temperature

Oil temperature Winding temperature technically not meaningful, since the oil temperature follows the winding temperature. Incorrect parametering may lead to relay fl utter

Winding temperature Oil temperature

Winding temperature Winding temperature


19BA 2076/04/01


Example:

Transformer with the following cooling stages and settings:

ONAN, basic transformer cooling ONAF-1 First fan bank, switches on when the oil tem-

perature exceeds 50 C, switches off via the oil temperature at 45 C with a hysteresis of 5 K.

ONAF-2 Second fan bank, switches on when the oil temperature exceeds 60 C, switches off via the oil temperature at 55 C with a hysteresis of 5 K

Cooling stage switching (e.g. switching between Cooling 1 and Cooling 2) results in switching of the parameters for calcu-

Hysteresis

HysteresisSwitch point S2

Switch point S1

Relay S1

Relay S2

Cooling 0(ONAN)active

Cooling 1(ONAF-1)

active

Cooling 2(ONAF-2)

active

Cooling 1(ONAF-1)

active


lating the winding temperature. The current parameter set is always the parameter set for the currently active cooling stage.

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Load-dependent cooling stage activation

The load-dependent cooling stage activation function is designed to switch on cooling stages in the event of rapid or strong load changes, based on exceedance of a parameteriz-able load. This function prevents the transformer reaching a temperature limit value through cooling. It can be useful if one of two transformers running in parallel mode fails, causing the second to handle twice the load, or for generator transformers that are operated with overload for short periods.

The function is parameterized via the following parameters:

The CT activation limit value, which corresponds to the transformer load in percent. The cooling stages are activated if this value is exceeded.

The delay time describes the duration for which the cooling stages keep running once the temperature has fallen below the limit value described above.

Example: Set the parameters to 80 % and 30 min. respectively to activate the cooling stages at 80 % transformer load and keep them running for 30 minutes after the load has fallen below the limit value.

Cooling system control via the temperature limit value is active in the background. If the cooling stage was already activated through exceedance of a temperature limit value it remains

active. If a temperature limit value is still exceeded after the delay time described above the cooling stage remains active until the temperature falls below the limit value.

Relay S1

Relay S2

Delay time

80 % transformerload at Cooling 2

80 % transformerload at Cooling 1

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Periodic cooling stage activation

The periodic cooling stage activation function is designed to activate the cooling system for a short time after a specifi ed interval. This function is useful for transformer cooling systems that are only switched on occasionally. It can prevent seizing of bearings as a result of long idle time.

The function is parameterized via the following 3 parameters:

Turn-on delay (1-1000 h): After this time the cooling stages are switched on for the fi rst time.

Operating time (5-120 min.): Operating time of the individu-al cooling stages

Interval (10-1000 h): The cooling stages are switched on periodically based on the interval setting.

This function must be activated for each individual cooling stage during parametering. It enables selected cooling stages to be switched on periodically while others remain switched off, e. g. pumps in a cooling system.

The individual cooling stages are switched on/off at 1-minute intervals in order to avoid load peaks.

Operatingtime

Relay S1

Relay S2

1 min. 1 min.

t

t

Interval IntervalTurn-on

delay

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5.8 Load cycle mode

The load cycle mode function ensures that the load is distri-buted evenly across the cooling units (usually fans) connected to switching contacts S1-S4. In load cycle mode the relays for the corresponding switching contacts are activated sequen-tially at adjustable load cycle intervals. The LED display and the winding parameters of the active cooling stage remain unchanged.

Please note that only cooling stages of similar type (usually several fan banks) should be operated in load cycle mode.


Switchpoint S3

Switchpoint S2

Switchpoint S1

Relay S1

Relay S2

Relay S3

Relay S1

Relay S2

Relay S3

without load cycle mode


Cooling 1(ONAF-1)

active

Cooling 2(ONAF-2)

active

Cooling 3(ONAF-3)

active

. . .

. . .

. . .

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Messko

5.9 Device self-monitoring

The EPT202 has a self-monitoring function.

The following faults are detected and reported via the software and the ERROR relay:

Supply voltage failure (only alarm via ERROR relay possible) Input sensor faulty (line interruption or short circuit) Analog oil temperature output open Analog winding temperature output open Internal hardware fault

The switching characteristic of the ERROR relay is parameteriz-able (see also Section 4.9):

In standard mode supply voltage failure or complete device failure is not reported via the ERROR relay. This function can be used for applications in which the supply voltage tends to be interrupted for short periods due to switching processes (e. g. between internal and mains supply). In fail safe mode as described below an error message would be generated with each switchover sequence.

In fail safe mode the ERROR relay reports each of the errors described above.

To check the signaling path for the ERROR relay an error has to be generated manually by pulling the connector for an analog output or the input sensor. For safety reasons please ensure that the EPT202 is switched out before pulling or inserting a connector.

An input sensor faulty error results in the following EPT202 response:

The winding temperature can no longer be calculated, since the oil temperature is no longer available as the basis of the calculation.

Both temperatures are no longer displayed. The residual lifetime calculation is suspended. Since the current oil and winding temperature is unknown

when this error occurs, for safety reasons all contacts for controlling the fan groups are activated.

The contacts for alarm and trip messages are not activated but remain in the state before the sensor failure.

5.10 Analog outputs

The EPT202 has two analog outputs for remote oil tempera-ture and winding temperature transmission. For both analog outputs three fi xed output signals are available:

0-20 mA (fault signal > 22 mA) 4-20 mA (fault signal > 22 mA) 4-20 mA (fault signal < 3.6mA)

The fault signal is output if the oil temperature sensor is faulty. The electronic analysis system (digital display, moving coil in-strument etc.) responds with an unrealistic display to indicate that there is a fault.

In addition two adjustable output signals are available:

Voltage output: Freely adjustable between 0.0-1.0 V and 0.0-10.0 V Current output: Freely adjustable between 0.0-1.0 mA and 0.0-20.0 mA

The adjustable output signals can be used to generate custo-mized such as 0- 5 V or 0-10 mA.

The adjustable signals do not result in a fault signal if the oil temperature sensor fails.

Please ensure that the analog outputs match the measuring and display ranges of the EPT202 and the connected electro-nic analysis system and the maximum burden resistance (for current signals) or minimum burden resistance (for voltage signals).

5.11 Data logging

The EPT202 has an internal memory for storing data. The log-ging interval between two datasets is freely parameterizable.

In addition a dataset is stored after an event.

The following events result in dataset logging:

Supply voltage on/off Test mode activated/deactivated Trip activated/deactivated Alarm activated/deactivated Device fault activated/deactivated Switching contacts (S1-S4) activated/deactivated Device lockout inactive/active

The data memory has capacity for approx. 32,000 datasets. With a time interval of 10 minutes datasets can therefore sto-red for a period of approx. 7.5 months. The longer the logging interval the longer the period. The data memory has 128 seg-ments. Once the memory is full it is sequentially overwritten segment by segment, starting with the oldest data.

The data logger is read via the visualization software and the data are save in an Excel fi le. The data analysis can be carried out in Excel as required.


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6 Operation

6.1 Front panel

The front panel is basically identical for all four versions (see Fig. 6), with the terminals for the EPT202 for panel mounting and the 19 rack fi tted at the back and the SPI bus fi tted internally.

The 8-line LCD display shows the menus, measured values and parameters.

Via a USB cable the device can be connected with a PC for parametering or data transfer.

Additional modules such as the EPT202CT with 2 additional CT inputs can be connected via the SPI bus.

The status LEDs indicate the following operating states:

green POWER LED lit: device running green POWER LED fl ashing: key lock released

yellow ALARM LED lit: ALARM contact is operated

red TRIP LED lit: TRIP contact is operated

red ERROR LED lit: device fault

yellow LED S1...S4 lit: contact S1...S4 and the corresponding parameter set is activated

6.2 Menu control

Use the 5 control keys to display parameters and measured values.

Parameters can only be modifi ed once the key lock has been released.

A more detailed description of the menu structure and navi-gation can be found in the quick reference guide (BA2097).

Temperature display mode

The device usually operates in tempe-rature display mode. If a menu item is selected and the device is not operated for 30 seconds it automatically switches to the higher-level menu or temperature display mode.

Messwertanzeige O IL - T E M P

65 , 8 C

W IN D I N G - TE M P

74 , 2 C

NOTE

The LCD display is dimmed after approx. 10 minutes. Press any key to activate the display.

Fig. 6

4 Control keys

5 SPI bus

6 USB interface

Use the 5 control keys to switch between the individual menus, edit parameters and reset measured values.

1 Status-LEDs

2 Terminals

3 LCD display

6 Operation

25BA 2076/04/01

Messko

Device faults are indicated in bottom line in temperature display mode.

The individual error messages and pos-sible causes are described below:

: The connected sensor is faulty Line interruption or loose contact Incorrect input sensor paramete-rized

: Indicating instrument faulty Line interruption or loose contact Bridge terminals 2 and 3 if the output is not used

: see

: Loss of supply voltage

Releasing the key lock and changing the key code

To change or release the key lock simultaneously press and while the device is in temperature display mode.

The key lock is factory-set to and not active with this setting. The key code can be chan-ged and thus activated when the menu is accessed for the fi rst time. The key code can only be modifi ed if it is released.

To release it, simultaneously press and while the de-vice is in temperature display mode and enter the key code. The green POWER LED then starts fl ashing.

Changing to menu level

To change from temperature display mode to menu level (navi-gate to the main menu ) press .

Switching between main menus

The main menus are arranged in aloop. Press or toswitch between the different main menus.

6 Operation

Einloggen

E nt e r K e y- C o d e

12 5 6 _

KeyCode ndern

C ha n g e K ey - C o d e_

00 0 0 _

Messwertanzeige O IL - T E M P

65 , 8 C


74 , 2 C

Sensor defekt O IL - T E M P

65 , 8 C


74 , 2 C O TI - S e n s or d e f ._

PeakValues_Generell < -P E A K - V AL U E S - > M ax . O i l -T e m p . M in . O i l -T e m p .

M ax . W i n d in g - T e m p M in . W i n d in g - T e m p M ax . L o a d -C u r r e n t M ax . A m b i en t - T e m p M in . A m b i en t - T e m p

oder



oder +

Lastfaktor L oa d - F a c to r_

0 ,9 1 _ _ _ _

Selecting a menu item

Press or toselect the required menuitems and press .

To return to temperature display mode select the main menu header and press .

Menu functions

If the submenu is only used for display purposes and no parameters are modifi ed, press to return to the higher-level menu.

To modify a parameter select it with or and confi rm with .

The MIN and MAX values can be reset by pressing or .Press to confi rm. The peak value is overwritten by the current value.

For menu items with sub-menus select the heading ( or ) andpress to returnto the higher-level menu.

CT-Ratio C T- R a t i o

1 20 0 : 1

S av e ? Y ES N O

oder +

Max ltemp

M ax . O i l -T e m p .

58 , 2 C

S av e ? Y ES N O

oder +

Schaltpunkt generell S 3 A L A R M __ _ _ _ _ Co n f i g u ra t i o n S wi t c h - P oi n t H ys t e r e s is D el a y - T i me oder +

26 BA 2076/04 /01

7 Display and parametering

7 Display and Parametering

This section describes the individual menus and parameters that are displayed on the device and can be parameterized via the control keys.

Parametering of the EPT202 via the visualization software is described in Section 8.

The date and time are kept in memory for at least 2 weeks without supply voltage. After this time the data are lost.

The current date and current time must be set when the device is connected for the fi rst time or reconnected after approx. 2 weeks without power supply. The device automatically opens the relevant menu item.

The EPT202 must be fully parameterized in order to ensure correct function.

The following description of the individual menu items is based on the parametering sequence. The menus are arranged to offer convenient navigation during operation. The menu struc-ture is explained in quick reference guide BA 2097.

7.1 Input and output confi guration

This menu is used for confi guring the inputs and outputs and turning the win-ding temperature calculation on or off.

Sensor input

If the menu is se-lected a further submenu appears with 3 menu items for selecting the input sensor , for setting an offset correction and for setting a correction for compen-sating temperature losses in the thermo-meter pocket.

Select the input sensor in the menu .

Please also refer to Section 5.2 on page 16.

The offset correction can be use to compensate constant temperature deviations resulting from unfavourable location of the thermometer pocket, for example. Simply enter the offset value. For example, if the measurement is consistently 3.0 C too low, enter an offset value of +3.0 C and confi rm.

The temperature correction function can be used to compen-sate measurement errors caused by heat losses at the thermo-meter pocket. If this function is activated the system calculates an internal correction value based on empirical data. The correction value takes effect at oil temperatures above 30 C and increases linearly.

Parametering the analog outputs

This menu is used for parametering the output signals for the analog oil tempe-rature output. The analog output for the winding temperature is parameterized in the same way.

The fi rst 3 signals (0-20 mA and 2 x 4-20 mA) are preset out-put signals.

Use menu item to scale the 4th mA output signal between 0-1 mA and 0-20 mA. Use menu item to scale the voltage signal between 0-1 V and 0-10 V.

The scalable signals can be selected in the menu shown above.

Ambient temperature logging

In this menu item ambient temperature logging can be activated.

Further information about this function can be found in Section 5.3 on page 16.

Only the 4-20 mA input can be used as input sensor for the ambient temperature. In this case a Pt100 sensor must be used for the top oil temperature input.

Parametering of the input sensor for the oil temperature is then automatically set to Pt100.

ERROR relay confi guration

The switching characteristic of the ERROR relay is confi gurable. There are 2 modes, and . In fail-safe mode an error message is generated if the supply voltage fails or if the device fails com-pletely, in standard mode no error message is generated. See also Section 4.9.

Winding temperature on/off

In this menu item the winding tempera-ture can be turned on or off.

This means that all functions and calcu-lations based on the winding tempera-ture are deactivated.

For further information please refer to Section 5.2

7.2 Cooling stage-specifi c parameters

In this menu the cooling stage-specifi c parameters, which also form the basis for calculating the winding temperature, are parameterized.

I/O Config_Generell < - I / O C ON F I G - > O il - T e m p .I n p u t

Oi l - T e m p. O u t p u t A mb . T e m p . O n / O f f

E rr o r - R e la i s W in d i n g Co n f i g

W in d . T e m p. O u t p u t

ltemp Eingang Gen. - OI L - T E M P. I N P U T -

I np u t - S i gn a l O ff s e t - C or r e c t ._T em p - C o r re c t i o n_

Eingang ltemp O il - T e m p .I n p u t I np u t - S i gn a l

4 -2 0 m A_P t1 0 0 _

S av e ? Y ES N O

Offsetkorrektur O il - T e m p .I n p u t

O ff s e t - C or r e c t ._

3, 0 K

S av e ? Y ES N O

ltemp Ausgang Oi l - T e m p. O u t p u t 0- 2 0 m A ( > 2 2 ) 4 - 2 0 m A ( < 3 , 6 )

4- 2 0 m A ( > 2 2 ) 0 -1 0 , 0 m A_ _ _0 - 5 , 0 V__ _ _

A dj u s t m A- O u t p u t A dj u s t V -O u t p u t_

ltemp Ausgang mA Oi l - T e m p. O u t p u t A dj u s t m A- O u t p u t

0 -1 0 , 0 m A_ _ _

S av e ? Y ES N O

Umgebungstemp an/aus

A mb . T e m p . O n / O f f

A mb i e n t - Te m p O n_A mb i e n t - Te m p O f f

S av e ? Y ES N O

Error-Relais

E rr o r - C o nf i g

F ai l - S a f e S ta n d a r d _

S av e ? Y ES N O

Wicklung ein/aus

W in d i n g - Co n f i g

W in d i n g On Wi n d i n g O f f

S av e ? Y ES N O

Winding Generell < - C O O L IN G - > C T/ L o a d - Cu r r e n t_H ot s p o t - Fa c t . ( H ) C oo l i n g Co n f i g C 0 O N A N_ _ _ _ _S 1 O N A F- 1_ _ _S 2 O N A F- 2_ _ _

27BA 2076/04/01

Messko7 Display and parametering

Current transformer ratio, load current and load factor

Menu item con-tains 3 submenus for parametering the CT ratio and displaying the actual load current and the load factor.

The EPT202 has an input for the CT transformer current that is used for mapping the actual transformer load. The transformer ratio is parameterized in the menu. It forms the basis for calculating the actual transformer load current. The CT ratio is normalized to 1. For example, a value if 750:1 must be parameterized i.e. if the transformer nameplate shows a transformer ratio of 1500:2.

The menu indicates the actual load current.

In the menu is actual load factor, calculated as actual load current / rated load current, is displayed.

Hotspot factor (H)

The hotspot factor is an empirical value used for determining the hotspot tempe-rature according to IEC 60076-7.It depends on the transformer size, the short-circuit impedance and other factors.

If the value is set to 1.0, the mean temperature of the top winding layer is calculated according to IEC standard and displayed.

For the calculation according to ANSI standard this value must be set to 1.0, since it is not used in the calculation.

Number of cooling stages

The number of cooling stages (1-5) is set in the menu. If the transformer has 3 cooling stages, for example (ONAN, ONAF-1, ONAF-2), the value must be set to 3. During parametering please note that the fi rst cooling stage is always the basic transformer cooling stage, i.e. it is not activated with an EPT202 relay.

The basic cooling stage is displayed as C0, the other cooling stages as S1-S4. These are then also activated with relay con-tacts S1-S4. The cooling stage IDs can only be changed in the visualization software.

CT Generell - CT / L O A D CU R R E N T -

C T- R a t i o Lo a d - C u rr e n t_L oa d - F a c to r_

CT-Ratio C T- R a t i o

1 20 0 : 1

S av e ? Y ES N O

Laststrom L oa d - C u r re n t

1 08 9 A

Lastfaktor L oa d - F a c to r_

0 ,9 1 _ _ _ _

Hotspot Faktor H ot s p o t - Fa c t o r

1 ,3 _

S av e ? Y ES N O

Anzahl Khlstufen C oo l i n g Co n f i g M ax . C o o li n g

3

S av e ? Y ES N O

Cooling stage-specifi c parameter

Each cooling stage has a submenu with menu items for parametering the rated CT current, the gradient, the winding exponent and the time constant.

Rated CT current

The rated CT current is the current pre-sent at CT transformer if the transformer is operated with rated load. For each cooling stage the rated CT current can be set between 0.5 A and 5.0 A.

The rated CT current is calculated as the rated transformer current divided by the CT transformer ratio.

Example: Rated transformer current IN = 820 ACT ratio = 1000:1ICT = IN / = 820 A / 1000 = 0.82 A

Gradient gr

The gradient indicates the temperature difference between oil and winding temperature at rated load (for hotspot factor H = 1.0). The gradient can have a different value for each cooling stage. Range:0.0 - 50.0 K.

Winding exponent y

The winding exponent y can be set between 1.0 and 2.0. IEC 60076-7 spe-cifi es the following values for different cooling types:

Cooling ON.. y = 1.3Cooling OF.. y = 1.6Cooling OD.. y = 2.0

For the calculation according to the ANSI standard y is the result from (2 x m). According to the ANSI standard m is between 0.8 and 1.0.

Time constant

A sudden change in load current does not generate a sudden change in winding temperature. It approaches the actual value based on an exponential function. If the load current increases suddenly the winding temperature reaches 63.5% of its fi nal value after time and 95% of its fi nal value after 3 .

The time constant can be set between 0.0 and 30.0 minutes for each cooling stage.

S1 generell S 1 O N A F- 1 _ _ _R at e d C u rr e n t_G ra d i e n t (g r )

W in d i n g Ex p o n e n t T im e C o n st a n t_

Nennstrom S 1 O N A F -1_ _ _ _R at e d C u rr e n t_

2 ,0 0 _ _

S av e ? Y ES N O

Gradient S 1 O N A F -1_ _ _ _G ra d i e n t (g r )

2 6, 0 _K

S av e ? Y ES N O

Wicklungsexponent S 1 O N A F -1_ _ _ _

W in d i n g Ex p o n e n t

1 ,6 _

S av e ? Y ES N O

Zeitkonstante S 1 O N A F -1_ _ _ _T im e C o n st a n t_

6 _ m in

S av e ? Y ES N O

28 BA 2076/04 /01

7.3 Switching contacts for cooling system control

The switching contacts for controlling the cooling system are parameterized in menu . The fi rst 3 menu items are used for parametering the special functions load cycle mode, periodic cooling stage activation and load-dependent cooling stage activation.

The number of switching contacts shown in the menu appear depends on the number of cooling stages set in menu .

Load cycle mode

This menu item is used for parametering the interval at which the relay contacts for controlling the cooling stages associated with load cycle mode are alternated. Further information about the load cycle mode function can be found in Section 5.8.

To deactivate load cycle mode set the load cycle interval to 0 h.

Periodic cooling stage activation

The periodic cooling stage activation function is used to activate the cooling stages assigned to this function for a parameterizable interval. Further information about this function can be found in Section 5.7.

The following 3 parameters must be set:

Turn-on delay:

Once this time has elapsed the cooling stages are activated for the fi rst time. This parameter can be used to initiate activation at a particular time on a particular day of the week.

To this end the time remaining up to this time must be calcu-lated and parameterized.

Operating time:

The operating time specifi es how long the cooling stages are activated. If several cooling stages are activated, activation of the individual stages takes place with a time delay of 2 minutes in order to avoid voltage spikes.

Interval time:

The next activation takes place after the interval time has elapsed. To activate the cooling stages every 2 weeks, for example, set an interval time of 336 h. The interval time can be set between 2 - 1000 h.

Cool Contact Generell < -C O O L . C ON T A C T - >

A lt e r n a t e_A ut o m a t . -C o o l i n g L oa d - C t r l. - C o o l . S 1 O N A F- 1_ _ _S 2 O N A F- 2_ _ _

Lastwechselintervall

A lt e r n . - In t e r v a l

10 0 h

S av e ? Y ES N O

Automatic Cooling A ut o m a t . -C o o l i n gP ow e r - u p D e l a y O pe r a t i o n T i m e In t e r v a l T i m e

Einschaltverzgerung A ut o m a t . -C o o l i n g P ow e r - u p D e l a y

70 h

S av e ? Y ES N O


Load-dependent cooling stage activation

With load-dependent cooling stage activation the cooling stages are activated when a parameterized load factor is exceeded.

Further information about this function can be found in Sec-tion 5.7.

The function can be activated and deac-tivated via menu item . Activation activates all cooling stages, if the corresponding load factor is excee-ded.

The cooling stages are activated if the activation limit value is exceeded. Set the load factor in %. This is the transformer load in % depen-ding on the currently active cooling stage.

The switch-off delay time specifi es how long the cooling stages remain activated once the load has fallen below the ac-tivation limit value parameterized above. The value can be set between 5 - 120 minutes. After this time has elapsed the cooling stages are deactivated again, unless a temperature limit value was exceeded in the meantime. After this time has elapsed the cooling system is once again control-led via the temperature limit value.

Parametering the switching points

Each cooling stage activated via swit-ching points has a submenu for confi gu-ring the switching point and setting the switching point, the hysteresis and the delay time.

Menu item has a submenu for setting the switching characteristic and confi guring activation and deactivation, activating/deactivation load cycle mode and periodic cooling stage activation

Switching characteristic:

The contact switching characteristic can be set to 2 different modes. In contrast to standard mode, in fail-safe mode the contacts are closed even if the supply voltage fails.

Auto Laufzeit A ut o m a t . -C o o l i n g O pe r a t i o n T i m e

3 0 m in

S av e ? Y ES N O

Auto Intervallzeit A ut o m a t . -C o o l i n g In t e r v a l T i m e

33 6 h

S av e ? Y ES N O

Lastab generell L oa d - C t r l. - C o o l .C on f i g O n/ O f f_

A ct i v . - T hr e s h o l d O pe r a t i o n T i m e

Lastab Konfig L oa d - C t r l. - C o o l . C on f i g O n/ O f f_

L oa d - C t r l. O n Lo a d - C t rl . O f f

S av e ? Y ES N O

Lastab Aktivierung L oa d - C t r l. - C o o l . A ct i v . - T hr e s h o l d

8 0 %

S av e ? Y ES N O

Lastab Nachlaufzeit L oa d - C t r l. - C o o l . O pe r a t i o n T i m e

3 0 m i n

S av e ? Y ES N O

Contact S1 S 1 O N A F -1 _ _ _ _C on t a c t Co n f i g S wi t c h - P oi n t H ys t e r e s is D el a y T i me

Contact Config S 1 O N A F -1 _ _ _ _C on t a c t Mo d e A ct i v a t i on

D ea c t i v a ti o n A lt e r n a t e_

A ut o m a t . -C o o l i n g

Contact Mode S 1 O N A F -1_ _ _ _C on t a c t Mo d e

Co o l . F ai l - S a f e C oo l . S t an d a r d

S av e ? Y ES N O

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Activating the switching contacts:

Activation of the cooling stages and their contacts is confi gured in the menu.

With the switchingpoint is permanently active.

is used to activate the switching point if the oil temperature is exceeded

is used to activate the switching point if the winding temperature is exceeded

Deactivating the switching contacts:

In is used to confi gure the temperature at which the cooling stages and the associated switching contacts are deactivated. This menu is inactive if permanent activation is enabled via .

Activating load cycle mode:

With load cycle mode is activated for this cooling stage.

Further information about load cycle mode can be found in Section 5.8:

Activation of periodic cooling stage activation:

With periodic cooling stage activation is activated for this cooling stage. Further information about this function can be found in Section 5.7

Switching point

Menu is used to set the temperature switching point for activating the respective cooling stage and the corresponding switching con-tact.

Hysteresis

The hysteresis is set in the menu. The cooling stage and the asso-ciated switching contact is deactivated once the temperature falls below the switching point minus the hysteresis.

Example: Switching point 70 C, hysteresis 5 C: the cooling stage is deactivated at 65 C.

Contact Aktivierung S 1 O N A F -1_ _ _ _

A ct i v a t i on

Ma n u a l On Oi l - T e m p.

Wi n d i n g -T e m p . S av e ?

Y ES N O

Contact Deaktivierung S 1 O N A F -1_ _ _ _D ea c t i v a ti o n

O il - T e m p . Wi n d i n g -T e m p .

S av e ? Y ES N O

Contact Lastwechsel S 1 O N A F -1_ _ _ _

A lt e r n a t e_

A lt e r n a t e O n Al t e r n a te O f f

S av e ? Y ES N O

Contact AutoCool S 1 O N A F -1_ _ _ _

A ut o m a t . -C o o l i n g

A ut o . - C o ol . O n Al t e r n a te O f f

S av e ? Y ES N O

Schaltpunkt S 1 O N A F -1_ _ _ _S wi t c h P oi n t

7 5, 0 C _

S av e ? Y ES N O

Delay time

The menu can be used to set a delay time. In this case the switching contacts are activated with a delay of, say, 2.0 seconds after the temperature limit is exceeded. This can be used to minimize voltage spikes, for example, by switching on two cooling units with a time delay.

7.4 Switching contacts for alarm messages

Switching contacts S5 (ALARM) and S6 (TRIP) are designed to generate alarm, trip or warning messages.

Contacts S1-S4 are also available for alarm messages, if they are not used for controlling the cooling system. If the transformer has 3 cooling stages, for example, (of which 2 can be activated with switching contacts), con-tacts S3 and S4 can be used to generate further warning messages.

The switching contacts for warning messages differ from the contacts for controlling the cooling stages in that they are not activated in the event of an oil temperature input sensor fault.

This menu also contains the test function for the switching contacts. It offers a convenient method for testing the signa-ling path after installation or revisions.

Test function:

Selecting the menu item brings up a further submenu for specifying whether the switching contact test is to be carried out with or without the switching contacts for alarm and trip messages.

Please note that a test that includes the alarm and trip con-tacts may generate signals that switch off the transformer.

After the selection a window appears in which a (test) temperature is displayed. This temperature can be modifi ed with the Up or Down arrow key. The simula-ted temperature has no effect on the calculation algorithms within the device. It only affects the switching contacts.

Switching contacts:

Each switching contact has a sub-menu for confi guration and setting the switching points, the hysteresis and the delay time.

Hysterese S 1 O N A F -1_ _ _ _

H ys t e r e s is

5, 0 C _

S av e ? Y ES N O

Verzgerung S 1 O N A F -1_ _ _ _

D el a y - T i me

2, 0 s _ _

S av e ? Y ES N O

Switch Cont. generell < -S W I T C H -C O N T . - > T es t - F u n ct i o n_S 3 A L A R M__ _ _ _ _S 4 T R I P_ __ _ _ _ _S 5 A L A R M I I_ _ _S 6 T R I P II_ _ _ _

Auswahl Testfunktion -T e s t - F UN C T I O N -- A l a r m / Tr i p + A l a r m / Tr i p

Testfuktion T ES T - F U N CT I O N_! ! a c t i v e ! !

2 0, 0 C _

Schaltpunkt generell S 3 A L A R M __ _ _ _ _ Co n f i g u ra t i o n S wi t c h - P oi n t H ys t e r e s is D el a y - T i me

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Confi guration:

The submenu can be used to specify whether the contact is activated via the oil or winding tempe-rature. Alternatively the contact can be deactivated with .

The switching point, hysteresis and delay time are set in the same way as the switching contacts for controlling the cooling stages (see Section 7.2).

7.5 Lifetime consumption calculation

In this menu the lifetime consumptioncalculation is parameterized and displayed.

A more detailed description of the life-time consumption calculation can be found in Section 5.5.

Life-cycle consumption calculation confi guration

This menu item can be used to confi gure the calculation algorithm (calculation according to ANSI or IEC standard) or deactivate the calculation.

Calculation according to ANSI standard C57.91-1995 (+errata)

This option is recommended for transformer designs based on the ANSI and IEEE standards.

Calculation according to IEC 354, second edition 1991-9

This option is recommended for transformer designs based on IEC standards.

Deactivating the calculation (OFF)

If the device is installed at a transformer as a retrofi t and the expected residual lifetime is unknown, the calculation algorithm can be deactivated

Expected service life

This menu item can be used to parame-terize the expected service life for the transformer insulation system.

Menu item

This menu item indicates the current lifetime consumption.


7.6 Menu

This menu can be used to parameterize default settings for the data logging function. This function can only be used with the additional visualization software.

Further information about this function can be found in Sec-tion 5.10 on page 23.

Menu item

This submenu is used to set the current time and date.

This menu also appears when the device is switched on for the fi rst time or after a prolonged period.

Menu items and

Menu item indicates the number of currently saved datasets.

In menu item the data logging interval can be set if the key lock is released.

The default setting is 10 minutes.

7.7 Menu

This menu contains the following min and max values:

Max. oil temperature Min. oil temperature Max. winding temperature Min. winding temperature Max. load current Min. ambient temperature Max. ambient temperature

The max. values can be reset by pressing the or key if the key lock is released.

A reset resets the peak values to the current measured values.

The peak values are updates every minute.

Lebensdauer generell < -L I F E - C ON S U M . - > C on f i g L if e - C o n .

n or m a l L if e _ L if e - C o n su m p t i o n

Lebensdauer Config

C on f i g L if e - C o n .

C al c . A N S I 1 1 0 C_Ca l c . I E C 9 8 C _

O ff _S av e ?

Y ES N O

Lebensdauer erwartet

N or m a l L if e_

3 0 Y e a r_

S av e ? Y ES N O

Lebensdauer verbr.

L if e - C o n su m p t i o n

5 ,8 %_

NOTE

The device does not automatically switch between summer und winter time. Please note that this may lead to time differences.

Datalog generell < -D A T A - L OG G I N G - >

D at e / T i m e_D at a L o g - Co u n t s

D at a L o g - In t e r v a l

Datum D at e

[ dd . m m . y yy y ]

14 . 1 1 . 2 00 7_

S av e ? Y ES N O

Zeit T im e

1 0: 0 3 : 2 5

S av e ? Y ES N O

Datenstze D at a L o g - Co u n t s

1 17 1

Interval

D at a L o g - In t e r v a l

3 0 m i n

S av e ? Y ES N O

Schaltpunkt config S 3 A L A R M__ _ _ _ _ Co n f i g u ra t i o n

O ff _o il - T e m p ._

W in d i n g - Te m p ._S av e ?

Y ES N O

Schaltpunkt S 3 A L A R M__ _ _ _ _S wi t c h - P oi n t

8 5, 0 C _

S av e ? Y ES N O



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7.8 Operator data menu

This menu can be used to retrieve ope-rator data.

This information (with the exception of the RS485 address) can only be entered via the visualization software.

Set the RS485 address with the or key and confi rm.

Operator < - O P E R AT O R - >

L oc a t i o n T ra n s f o r me r N o ._M ea s u r i n g P o i n t_

I nf o R S4 8 5 - A d dr e s s_A dd r e s s Na m e

RS485-Adresse

R S4 8 5 - A d dr e s s_

2 _

S av e ? Y ES N O

Manufacturer < -M a n u f a ct u r e r - >

A rt i c l e No ._S er i a l N o.

M an u f a c t . D a t e I np u t R a ng e_

F ir m w a r e V e r s i o n F ir m w a r e D a t e_

7.9 Manufacturer data menu

This menu contains the following manufacturer-specifi c data:

Article number Serial number Date of manufacture Sensor input range Software version Software date

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8 Visualization software

Proceed as follows to install the visualization software:

1. Run the setup fi le from the \setup folder on the CD or a user-specifi ed location.

2. Select a language for the installation wizard.

3. The installation wizard will guide you through the installation. Click .

4. In the component selection window ensure that is ticked and click .

8.1 Installation of the visualization software for the EPT202

PLEASE NOTE

The installation procedure is described for Microsoft Windows XP, Service Pack 2. In other operating systems the installation procedure may be different.

5. Select the destination folder for installing the visualization software and click to continue.

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Messko

6. The software will now be installed on your computer. After the installation click .

7. The installation is now complete. Untick to exit the installation wizard without running the software. Click to complete the installation wizard.

Documents

BA2076_EPT202_en_Rev4