RPM 8 Manual

INSTRUCTION MANUAL FOR

RPM-8

Reactive Power Manager

Relay 8 Stage

CONTENTS

Sl.No. Topic Description Page No.

1.0 Introduction 1

2.0 Installation & Wiring 4

3.0 Settings & Programming 8

3.2 Menu Structure 11

4.0 Display & Menu Operations 12

5.0 RPM-8 Operation 21

6.0 Alarms in RPM-8 25

7.0 Technical Specifications 28

8.0 Warranty 32

Appendix-1 Guidelines for Cap. Bank selection 33

Appendix-2 Effect of high rate of load fluctuation 34

-1-

1.0 INTRODUCTION

Reactive Power Manager Relay (Model RPM-8) is designed for

automatic control of capacitor banks in 3 phase 4 wire LT distribution

systems. The relay maintains the system power factor at a set value,

under fluctuating load conditions, by connecting or disconnecting

capacitor banks to the 415V bus. The relay employs state of the art

micro controller design for measurement of reactive power

compensation required, system power factor, voltage and current. A

specially formulated optimization program for capacitor bank switching

ensures accurate power factor control at the set point and hunt free

operation.

RPM-8 is designed to control up to 8 capacitor banks. The front panel

arrangements and other features of the unit are explained in the

following sections:

1.1 Non uniform Banks: RPM-8 can accept capacitor banks whose

values are at random (i.e.) it is not necessary to connect banks in

ratios of 1: 1: 1: or 1: 2: 2: or 1: 2: 4: etc. The kVAR ratings of the banks can be in any random denomination. It is not necessary

that the banks should be in multiples of the smallest bank. This

feature helps in providing maximum kVAR compensation with

least number of banks (the number banks can go up to 8)

2

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1.2 Bank Configuration: The user will have facility to enter the

bank size of each bank (in kVAR) at the time of commissioning.

Any bank which is not connected will have to be entered as zero

kVAR. The banks whose values are entered as zero will be

treated as unconnected banks. The relay will not switch these

zero value banks in its normal operation. Consequently the time for PF correction will be minimized.

1.3 Automatic c/k selection: The user need not perform complicated

mathematics to calculate c/k ratio and set in the relay. The relay

will do the PF correction without the need for c/k ratio. It

automatically calculates the threshold kVAR by taking into

account the bank values already entered. Hence there is no need

to set the c/k ratio.

1.4 Accurate display of Power Factor: The unit uses a specially

designed measurement circuit, which facilitates accurate

measurement and steady display of PF, even in conditions where

harmonics are present.

1.5 Optimization of connected banks: RPM-8 will constantly

monitor the kVAR compensation required and select the right

combination of banks to ensure that the plant PF is maintained

very close or equal to the set value.

1.6 Hunt Free operation: A unique optimization program for bank

switching, combined with online monitoring of total reactive

compensation required as mentioned above, ensures that the relay

does not hunt at a bank value during load fluctuations. 3

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1.7 Multi parameter Display: RPM-8 has a 4 digits, seven segment,

super bright LED display on the front panel. The unit shows the

plant PF as a default display. On demand, the unit can also

display feeder current, bus voltage, kVAR, settings and bank

values.

1.8 Measurement sensitivity of 1%: The unit can continue PF

correction even when the load current goes up to 1% of the rated

value. Thus PF correction is ensured even in very low load

conditions (like in night times or during the initial stages of a

plant commissioning).

1.9 Alarms: RPM-8 provides an alarm contact whenever there is an

abnormality like over voltage, under current, CT polarity reversal, over compensation and under compensation.

1.10 Design Philosophy: RPM-8 uses a unique combination of two

powerful, state of the art integrated circuits one for doing analog measurements accurately and the other for doing the peripheral

functions efficiently. The analog IC carries out the measurement

of Voltage, current, active energy and apparent energy with the

accuracy levels required in energy measurement instruments. The

measured values are transferred to a high memory micro

controller with built in EEPROM which carries out the peripheral functions like display, switching logic and push button

access for menu options. Consequently, the circuit has very few

components, which increases the reliability of the device as a

whole. 4

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2.0 INSTALLATION & WIRING

2.1 Preliminary checks: The relay package consists of:

- 1 no. RPM-8 Relay - 2 nos. mounting clamps - 1 no. Instruction Manual - 1 no. Test certificate

Check the RPM-8 relay for any damage. If damaged, please

inform nearest L&T office or dealer. If found OK, follow the

instructions below for basic functional checks:

a) Remove the terminal cover from the rear terminal block and Connect 240 V AC supply at terminals 1 & 2.

b) Switch on the supply voltage. The display will show PFR8, the power factor and then the error code uCrr. The LEDs

marked Auto and Alarm will glow continuously. All other

LEDs will remain off.

If the unit has passed above checks, it is ready for panel

mounting.

5

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2.1 MOUNTING ON PANEL:

RPM-8 relay is designed for flush mounting on any control panel.

Please refer to the dimensional drawing shown below for

understanding the overall & cutout dimensions of RPM-8.

Provide a cut-out of 138mm x 138 mm on the panel. Push the RPM-8

relay through the cut out and fix the relay to the panel by means of the

two mounting clamps.

6

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2.3 WIRING OF RPM-8 RELAY ON PANEL:

Please refer wiring diagram shown below (the same is affixed on

top side of the unit). There are 4 groups of connections as

explained below:

a) Auxiliary supply to RPM-8: Please connect R phase voltage

of the capacitor bank panel to terminals 1 & 2 of the unit. Please

note that it should be 240 V AC 50 Hz supply (Phase to neutral

voltage). Phase is connected to 1 terminal and neutral is

connected to the 2 terminal of the unit. RPM-8 uses this supply

as the auxiliary supply for electronic circuit as well as

measuring voltage for PF and kVAR computation. 7

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b) CT input to RPM-8: The unit is suitable for connecting to CT secondary of either 1A or 5A rating. Please ensure that the CT

is on R phase. CT secondary is to be connected as follows:

1A rating Terminals 8 & 9 5A rating Terminals 7 & 9

c) Supply to Capacitor Bank contactor coil supply: RPM-8 is meant for connecting up to 8 capacitor banks through external

contactors. Consequently it provides 8 relay contact outputs.

- One terminal of all 8 contactor coils is to be connected to neutral of the contactor coil supply.

- The other terminal of each of the contactor coil has to be connected to RPM-8 terminals 17 to 24 as shown in the

wiring diagram.

- The phase supply of contactor coil should be connected to terminal 14 of RPM-8

d) Alarm Circuit: RPM-8 provides a change over contact at terminals 4, 5, 6.

this is an 8A rated contact and can be used for energizing a buzzer.

Note: Please ensure that:

a) The auxiliary supply is 240 V ac b) The CT is on the same phase as the auxiliary supply c) Earth connection to the relay is provided properly

8

-8-

The relay terminals are suitable for 2.5 sq.mm lugs. After

completing the wiring, fix the protective cover back on the terminal

block with the help of 4 screws.

3.0 SETTINGS & PROGRAMMING

3.1 FRONT PANEL OF RPM-8

As shown in Fig. 1 on page 9, the front panel of RPM-8 has the

following provisions:

3.1.1. 4 digit seven segment LED display:

The on line measured values and various set values will be

displayed in the seven segment display. The default display is

the plant PF. All other parameters are to be read by

manipulating the PBs as explained in Section 4.

3.1.2 A row of 8 nos. Capacitor bank status LEDs:

The row of 8 LEDs will indicate Capacitor bank (CB) on / off

status. Since the relay is meant for connecting up to 8 stages of

capacitor banks, there are 8 LEDs in a row, each with the bank

number associated with it.

If a particular LED is on, the respective CB is switched on. If

the LED is off, the respective CB is switched off. For example,

if LED 4 is on, capacitor bank 4 (CB04) is switched on.

9

-9-

Fig.-1

10

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3.1.3 A column 5 nos. Plant status Leeds:

The column of 5 LEDs indicates the plant status.

Lead LED will be ON during leading PF in the plant.

Lag LED will be ON during lagging PF in the plant.

Auto LED will be ON at all times, except when the PBs are pressed for some kind of manual operation. This LED indicates

that the RPM-8 relay is in auto mode of PF correction.

Manual LED will come ON whenever the RPM-8 relay is taken in to manual mode of operation.

Alarm LED will come ON if the plant goes into any of the alarm conditions as explained in Section 6.

3.1.4 Push buttons (PBs):

The 4 PBs, marked as Menu, , , and Enter are used to view display parameters, settings in the relay and to change /

programmed the settings in the relay as is explained in detail in

Section 4.

11

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....12

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4.0 DISPLAY & MENU OPERATIONS RPM-8 will display plant PF at all times as a default display. The

user can also view and programme many other parameters as

explained in following sections.

4.1.1 Main Menu: Connect auxiliary supply to RPM-8. Press the PBs in the

sequence shown in the table below and observe the respective

displays.

Operation Display

Press Menu d.dAt

Press d.SEt

Press P.SEt

Press d.dAt

It can be seen that, when the Menu PB is pressed, it opens up

three more sub menu options namely:

a) d.dAt : In this option, RPM-8 displays on line data.

b) d.SEt : In this option, RPM-8 displays all the parameter Settings.

c) P.SEt : In this option, user can change the set parameters.

(Programme settings).

13

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4.1.2 Online value display - d.dAt menu options: As mentioned earlier, this sub menu helps user to view on line

values. Following table shows the procedure to view on line

values:

Display of measured values

Operation Display Remarks

Press Menu d.dAt

Press Enter volt Displays value of phase to

neutral voltage of the bus. Press Enter 0246

Press Enter Cur Displays value of feeder

Current Press Enter 0127

Press Enter vAr Displays plant kVAr value

Press Enter 0056

Press Enter volt Repeat show

14

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4.3 Parameter settings display - d.SEt menu options

This sub menu helps the user to view all settings of various

feeder parameters as listed below:

Display of parameter settings


Press Menu d.dAt

Press d.Set Choose dset option

Press Enter TrPF Display of

Target PF Press Enter 00.98

Press Enter CtSl Display of CT secondary

rating (1A or 5A) Press Enter 0005

Press Enter Ctrt Display of feeder

CT ratio Press Enter 0050

Press Enter Td Display of interbank

Switch on delay (sec) Press Enter 0030

Press Enter Cb01 Display of kVAR

connected at Bank1 Press Enter 0005







.15

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Display of parameter settings (contd)










Press Enter TrPF Repeat show

4.4 Parameter programming - P.SEt menu option:

This option helps the user to programme the feeder parameters in

RPM-8. Once the feeder parameters are entered correctly, the

RPM-8 will do PF correction automatically, 24 hours a day.

Before entering into this menu, please keep the following feeder

related values at hand.

- the CT ratio - kVAR values of all banks connected at stages 1 to 8

- recommended time delay in sec. for inter bank switch on - target PF required to be achieved

Since Programming/changing the set values in the RPM-8 is an

authorized function, entry into P.Set option is made tricky. Please

refer table below for entering into PSEt option and do

programming. 16

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Parameter Programming P.SEt Menu


Press Menu d.dAt

Press d.Set Choose d.set option

Press P.Set Choose P.set option

Press Enter, then , and release Enter

TrPF Ready to change target

pF setting

Press Enter 00.95

(flash)

Set value of target PF

(00.95) will flash

Press for increase or for decrease of display value trPF

00.98

(flash)

The trPF value is

changed to 00.98 (will

remain flashing)

Press Enter (after

reaching the desired

value for trPF

setting)

CtSl

New trPF value is

registered. Next setting

CT sec. ready is ready to

be changed.

Press Enter 0005

(flash)

The set value of CT sec

(0005) will flash

Press for increase or for decrease of display value Ctrt

0001

(flash)

The new CtSl value is

changed to 0001 (1A)

(will remain flashing)

Press Enter (after


value of CtSL sec

setting)

Ctrt The CtSL value is


CT ratio is ready to be

changed

17

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Parameter Programming (contd)


Press Enter 0250

(flash)

The set value of CT ratio

(0250) will flash

Press for increase or for decrease of display value Ctrt

0300

(flash)

The new Ctrt value is

changed to 0300 (will

remain flashing)

Press Enter (after


value for Ctrt

setting)

Td The Ctrt value is


Cap. Bank switch on

time delay is ready to be

changed

Press Enter 0035

(flash)

The set value of time

delay (0035) will flash

Press for increase or for decrease of display value td

0030

(flash)

The new td value is

changed to 0030 sec


Press Enter (after


value for td setting)

Cb01

The td value is

registered. Next setting,

Bank 1 kVAR value is

ready to be changed.

Press Enter 0001

(flash)

Already set value of

Bank 1 kVAR (0001)

will flash

Press for increase or for decrease of display value Cb01

0005

(flash)

CB01 value is changed to

0005 kVAR

(will remain flashing) 18

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Press Enter (after


value for Cb01

setting)

Cb02

The new Cb01 value is




Press Enter 0003

(flash)

Already set value of

Bank 2 kVAR (0003)

will flash


0010

(flash)

CB02 value has been

changed to 0010 kVAR


Press Enter (after


value for Cb02

setting)

Cb03





Press Enter 0006

(flash)

Already set value of bank

3 kVAR (0006) will flash


0015

(flash)

CB03 value has been



Press Enter (after


value for Cb03

setting)

Cb04





19

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Press Enter 0008

(flash)




0020

(flash)

CB04 value has been



Press Enter (after


value for Cb04

setting)

Cb05





Press Enter 0010

(flash)




0025

(flash)

CB05 value has been



Press Enter (after


value for Cb05

setting)

Cb06





Press Enter 0015

(flash)




0030

(flash)

CB06 value has been


(will remain flashing) 20

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Press Enter (after


value for Cb06

setting)

Cb07





Press Enter 0020

(flash)




0035

(flash)

CB07 value has been



Press Enter (after


value for Cb07

setting)

Cb08





Press Enter 0025

(flash)




0040

(flash)

CB08 value has been



Press Enter (after


value for Cb08

setting)

TrPF


registered and the menu

will return to the first

parameter, the target PF

21

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As can be seen, there are a total of 11 parameters to be set

in the relay RPM-8 for satisfactory PF control.

5.0 RPM-8 OPERATION Main objective of RPM-8 relay to perform PF control in a LT

sub-station, by adding or deleting capacitor banks to / from a

three phase 415V bus.

RPM-8 can work in two modes - Auto and manual mode.

5.1.1 Operation in Auto mode: Whenever powered on, RPM-8 goes into auto mode operation by default (since its function is to

correct power factor automatically). No special activity is

required to bring the unit to auto mode.

In this mode, the unit continuously displays the plant PF,

measures the required kVAR for compensation and carries out

the power factor correction as per set parameters automatically,

without any intervention from the operator.

5.1.2 Operation in Manual mode: In this mode the user can add or delete capacitor banks by pressing the PBs on the front panel of

the RPM-8. The main purpose of providing this feature is to

check the wiring of RPM-8 to various banks, while

commissioning.

Procedure for manual operation is explained in following table.

22

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Manual addition of Capacitor banks from RPM-8


Press Menu d.dAt

Press d.Set Choose dset menu

Press Enter TrPF Display of target PF

Press Enter 00.98

Press Enter CtSL Display of CT Ratio

Press Enter 0005

Press Enter Ctrt Display of CT sec. Rating

Press Enter 0250

Press Enter Td Display of time bank switching

time delay Press Enter 0030

Press Enter Cb01 Display of Bank 1 kVAR value

Press Enter 0005

Press 0005 Bank 1 will be switched on.

Press 0005 Bank 1 will be switched off.

Press Enter CB02 Display of Bank 2 kVAR

Press Enter 0010




Press Enter 0015

.23

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Manual addition of Capacitor banks from RPM-8 (Contd.)





Press Enter 0020




Press Enter 0025




Press Enter 0030




Press Enter 0035




Press Enter 0040



24

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It should be noted that, RPM-8 goes to manual

Mode, only when any PB is pressed on the front

panel. If no PB is pressed for more than 30 sec

(approx.), the unit returns to Auto mode by itself.

In manual mode, the unit does not perform any measurement

or PF correction. The operator is expected to do the PF

correction by manually adding / deleting the capacitor banks.

In case it is required to do PF correction in manual mode for

a long duration, following provisions should be made on the

PF correction panel.

a) A pair of dedicated On/Off PBs for each capacitor bank b) An Auto/Manual switch - This switch has to be kept in Auto position when the PF

correction is to be done automatically by RPM-8. Wiring

should be such that, the phase supply of all contactor coils

will be connected to terminal 14 of RPM-8 only if the this

switch is in auto position.

- The switch is to be kept in manual position, when capacitor banks are to be added / deleted manually. When in manual

position, the phase supply of all contactor coils will be

disconnected to terminal 14 of RPM-8.

25

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- Thus the RPM-8 will be prevented to do any capacitor bank addition /deletion. However, the operator is free to add /

delete the capacitor banks by means of the dedicated PBs on

the main control panel. The RPM-8 will keep indicating the

PF and guiding the operator as to whether the target PF has

been reached or not.

6.0 ALARMS IN RPM-8 RPM-8 is designed to provide alarms under 5 abnormal

conditions. The alarm will be in the form of a change over

contact output at terminals 4, 5, 6 and an error code display on

the front seven segments LED. Following are the details of

alarms.

6.1.1 CT polarity reversal ( Ctrv ) : As explained earlier, the RPM-8 needs a 240 V AC input and

1A/5A CT secondary input for measuring PF and kVAR. Both

these inputs must be from the same phase in the APFC panel.

Some times the polarity of S1 & S2 terminals of CT may be

reversed when connecting the CT input to RPM-8. If this

happens, the PF calculations will go wrong. RPM-8 has a built in

check system for detecting CT polarity problem at the

commissioning stage itself.

Immediately after power on, with all banks in switched off

condition, the unit will show Ctrv display if there is a CT

reversal. At the same time the alarm contact will come on. This

alarm is indicated only for first 30 second. 26

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If this alarm is observed following must be done:

a) Switch off the voltage connection b) Short the CT secondary terminals at the terminal strip at

bottom of the panel

c) Interchange the CT connection at terminals 9 & 7of RPM-8 d) Power on again and ensure that the alarm is off.

6.2 Under Current Alarm (Ucrr):

RPM-8 is designed to work up to a load current level of 1% of

rated value. Some times this current can go even below 1% - any

PF correction at this stage may take the plant to leading PF state

for a long time - which may not be desirable. RPM-8 gives an

alarm Ucrr under such conditions and all the capacitor banks will be switched off so that plant PF does not go to leading PF

unnecessarily.

6.3 Over Compensation alarm ( OCPn ):

Many times, if the load is small, the PF may go lead even without

the least capacitor bank on. This is a case of over compensation this will result in pulling down average PF of the plant.

RPM-8 will give OCPn alarm under such condition

6.4 Under compensation ( UCPn )

There can be condition (particularly when the plant is on full

load) that all 8 banks are switched on but the target PF is not reached.

27

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This is a clear indication that the capacitor banks, as sized, are

inadequate for the plant. Under such conditions, RPM-8 will give

UCPn alarm so that user can re-configure the capacitor bank sizes.

6.5 Over Voltage alarm ( OvoL ) RPM-8 has a built in over voltage protection at +20% of rated

voltage (288 V). If the input voltage exceeds the 2885 V point, the RPM-8 will give OvoL alarm. At the same time all banks will

be switched off so that, the capacitor banks are saved from

exposure to over voltages.

28

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7.0 TECHNICAL SPECIFICATIONS OF RPM-8

Voltage Input 240V AC 15%, 50 Hz, Current Input 5A / 1A from CT secondary

(Field selectable)

Rated Frequency 50 Hz 2.5%

Accuracy of 1% 1digit between 0.7 lag to 0.8 lead

PF Display other ranges 2% 1digit.

Accuracy of other 2% digit

Display Parameter

Target PF setting 0.7 lags to 0.9 lead

CT ratio For 1 Amp secondary 1 to 6400

For 5 Amp secondary 1 to 1280

Threshold reactive Auto

Current setting (C/K ratio)

Bank selection Relay will recognize number of

Connected banks automatically

Bank configuration Suitable for non-uniform cap. Banks

Safety lock out time 30 sec 10%

Auto / Manual Operation Selectable ..29

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Capacitor bank a) 1 to 250sec in steps of 1 sec

Switching on delay for switching between two

different banks

b) 60 sec for same

Bank switching

(Timing Accuracy 10%)

Operational LEDs for all relays status Indicators LED for `ALARM`

LED for `AUTO/MANUAL`

LEDs for Lead / Lag

Four 7-segment displays for display of

Plant PF, Current, kVAR, ALARM-Codes,

capacitor bank values, Target PF, and

Time delay for switching.

Power Factor From 1% to 120% of rated current

Control Range

Burden < 0.3 VA at CT input at nominal

voltage

< 15VA at PT input at nominal voltage

Out put contacts a) 8 nos. N/O contacts for bank

contactor switching

b) 1 N/O for alarm

30

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Contact rating 250V AC, 5A for bank contactor

switching, 250V AC, 6A for alarm

Resistance to As per IEC 255-21-1/2 Class 1

Vibration &Shocks

Temperature Operating Temperature 00 to 60

0 C

Storage temperature -200 to 70

0 C

Case Front Bezel 144 x 144 mm

Panel Cutout 138 x 138 mm

Depth 100 mm

Weight 2 kg approx.

Electrical Performance specifications:

a) Insulation As per IEC 60255-5, 2 kV AC, RMS, 50 Hz for one

minute across independent circuits & 1 kV AC, RMS,

50 Hz for one minute across open contacts

b) Impulse withstand 5 kV (CM), 2kV (DM) peak, 1.2/50 micro sec, as per IEC

60255-5

31

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c) Surge Immunity As per IEC 61000-4-5, Level 4, 4 kV (CM), 2kV (DM)

d) Electrical fast Transient As per IEC 60255-22-4, 2 kV, 5 kHz

e) Conducted Disturbance As per IEC 61000-4-6, Level 3, 10V, 150 kHz to 80 MHz

f) Electro Static Discharge As per IEC 60255-22-2, air discharge 8 kV

g) Immunity to voltage Variations, dips and short Interrupts

As per IEC 61000-4-11, 200 ms

32

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8.0 WARRANTY

LARSEN & TOUBRO LIMITED (L&T) warrants that the

protective Relay model RPM-8 will meet L&Ts published specifications and will be free from defects in workmanship and

materials for a period of 12 months from the date of shipment.

L&Ts obligation under this warranty shall be limited to servicing or replacing the defective parts provided that notice of

such defects and satisfactory proof thereof is given to L&T by

its customer within the warranty period.

This warranty does not cover any defect caused by accident,

misuse, neglect alteration, modification or substitution of any of

the components or parts or any attempts at internal adjustment by

unauthorized service personnel.

Under no circumstances shall L&T be liable for any

consequential damage, resulting injury, loss or expense, directly

or indirectly, arising from the use of this product.

This forgoing warranty is in lieu of all other warranties

expressed or implied and is the sole and exclusive remedy for

any claim arising from the defect in the product.

.33

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Appendix-1

Guidelines for selection of Capacitor Bank size:

The RPM-8 relay will continuously evaluate the required kVAR

compensation and keep adding to the bus- thus bringing the plant PF

close to the set value. Some times, in operation, RPM-8 may not find

the closest match for the required kVAR and may stop adding. This

may result in a PF much less than the set target.

In order that RPM-8 brings the plant PF closest to target PF, the

system should have right denomination of capacitor banks as

required by the load conditions of the plant. To determine, the right

denomination of bank sizes (8 in total), following approach may be

followed:

Plant kVAR requirement

>100kVAR

Plant kVAR requirement

< 100kVAR

Bank

no.

Size (kVAR) Bank no. Size (kVAR)

1 X 1 X

2 2X 2 X

3 3X 3 2X

4 5X 4 2X

5 10X 5 3X

6 20X 6 5X

7 30X 7 10X

8 40X 8 15X

34

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Appendix-2

Effect of high rate of load fluctuation on PF control:

RPM-8 corrects PF by adding or deleting the connected capacitor

banks. As per the requirement of standards for Capacitor banks, the

banks are switched on / off with a set time delay. This inter bank

switch on delay is normally of the order of 15 to 30 sec.

In case the loads are fluctuating faster than this 15 sec, the time delay

can be reduced to the order of 5 sec. However, whenever the same

bank is switched on, the delay is preset to 60 sec as required by the

Standards. It can now be seen that whenever the load fluctuates in

less than 15 sec period, the switching action of RPM-8 may not

match with the correction requirements. This is mainly because, the

load changes before the action of RPM-8 is completed- with the

result that RPM-8 may not add capacitor at all.

This will lead to a situation where despite installing RPM-8, there is

a large gap between the target PF and actual plant PF reached like target PF may be 0.95, actual may be 0.87. It should be noted that

RPM-8 has brought the plant PF up to 0.87 it is not able to improve because it is not able to add additional capacitors due to rapid

fluctuations in load. This is particularly true for small plants where

the total kVAR itself is less than 10 kVAR.

For such applications it is advisable to have more small value banks-

like 1 kVAR, 1.5 kVAR etc. Alternately it is better to have individual

capacitors connected across each load.

Manufactured by

LARSEN & TOUBRO LIMITED,

KIADB INDUSTRIAL ESTATE,

HEBBAL, HOOTAGALLY,

MYSORE 570 018. INDIA.

Visit us @ www.lntmps.com

www.lntebg.com

www.larsentoubro.com

Reach us @ [email protected]

Part No. 4D060111 Rev. 4

Documents

RPM 8 Manual