Vacuum Circuit Breaker Instruction for Storage Erection, Operation and Maintenance

Type VBF1VDU28001-YN

Asea Brown Boveri Limited

Outdoor Vacuum Circuit Breaker Type VBF36

List of contents

1. General.

2. Design.

3. Function.

4. Erection.

5. Commissioning

6. Maintenance.

7. Breaker With Spring Charged Mechanism.

8. Breaker With Magnetic Actuator Mechanism.

9. Breaker Pole.

10. List Of Drawings.

VBF 36

Instructions for Erection, Operation & Maintenance.

1.0 General

1.1 Validitv :

This operating instruction is applicable for Outdoor Vacuum Circuit Breaker. type VBF.

1.2 Type designation : VBF 36 16 25

Outdoor Vacuum Circuit Breaker

Rated voltage -36 kV

Rated normal current

16 for 1600A

Rated breaking capacity- 25 kA

1.3 Specifications :Specifications are contained in the order documentation and on the name plate.

l ype - Vacuum Circuit Breaker VBF 36 Sr. Number - Brcakcr production Serial NumberYear - Year of manufactureStandard - IEC - 56 Rated voltage - 36 kVFrequency - 50 Hz Insulation level - 70/170 kV PeakNormal current - 1600 Amp. Short circuit Breaking current - 25 kA Duration of short circuit - 3 Sec.Short circuit making current - 63 kAOperating sequence - 0-0.3S-CO-3 Min -COWeight - 800 Kg. Approx.Auxiliary voltage Closing coil - Rated voltage of closing coilOperating coil - Rated voltage of opening coil Motor (if applicable) - Rated voltage spring charging Instruction Manual - 1VDU28001-YN

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1.4 Weight of the Circuit Breaker :

The weight of a complete circuit breaker is approximately 800 Kg. contributed by ...

Weight of poles-500 Kg.

Weight of mechanisrn-100 Kg.

Weight of mounting structure-200 Kg.

1.5 Storage :

1.5.1 General

The medium voltage circuit breaker type VBF are delivered firmly secured to the floor/bottom of

their containers or crates and must always be transported or stored with care. The circuit breaker

is transshipped in suitable packing in the open (OFF) position and with closing spring discharged.

1.5.2 Receipt :

Each delivery is to be checked on receipt for ...

*Completeness & correctness.

(Check against order and delivery documents)

*Any possible damage in transit & material losses.

Abnormality, if any, must be notified immediately to :

*ABB, Nashik

*The forwarding agent & the insurance company

2.Design (Fig. 1 )

The circuit breaker type VBF is a three pole vacuum circuit-breaker and designed in a column

type construction with spring stored energy operating mechanism mounted beneath the middle

pole. It consists of :

- Three breaker poles - FI - Support structure - Vs

- Control cabinet with spring stored energy mechanism - Cs

- Actuator rod and connecting links - Ds & Ts

- Pole support duct - Or

2

2.1 Breaker Pole :

The breaker pole (ref fig. 10) consists of

- Insulator body - 14

- Vacuum interrupier - 18

- Bottom current collector - 16

- Upper & lower terminal - 26 & 17

The poles are filled with a dry air (Nitrogen) individually at a pressure of 1 .2 bar (abs).

3. Function

3.1 The typical schematic circuit diagram (Fig. 2) of the breaker shows how the switching

ON and switching OFF commands are given to operate the circuit breaker.

The control circuit can also be referred in the order related engineering drawings.

3.2 Switching operations.

3.2.1 Starting conditions.

As supplied from Asea Brown Boveri Ltd., Nashik, the circuit breaker will be in open

position and closing spring in discharged condition. When the control supply is given to

the breaker, the closing spring will be charged automatically with the help of the spring

charging motor. After charging the spring, the circuit breaker will show the mechanical

indication of 'Spring Charged' from the mechanism observation window.

3.2.2. "Closing" Operation :

To close the circuit breaker, a "CLOSE" control element i.e. closing magnet is actuated ,

whereby the spring stored energy mechanism will release and thus the linkage system

moves the moving contact of all the three poles upward, closing the circuit breaker. This

movement also exerts a contact pressure of desired magnitude.

3.3.3 "Opening" Operation :

To open the circuit breaker, a "OPEN" control element i.e. opening magnet is actuated

whereby the energy stored in a opening spring gets released anci thus the linkage

system moves in reverse direction to move the moving contacts in downward direction,

thus separating the contacts of the circuit breaker.

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4. Erection

4.1 General:

- As supplied from M/s. Asea Brown Boveri Ltd., Nashik, the circuit breakers are complete in

all the respects with all the necessary setting for smooth and trouble free operations of the

breaker. All the moving parts of the circuit breaker are positioned correctly and coupled

together and they are well secured with the fasteners.

-It is recommended to use standard tools and standard practices for lifting and transport of the

circuit breakers at the time of erection, so as to avoid mechanical damages of the pole parts.

In general the lifting of the circuit breaker shall be done as shown in fig. 3.

4.1.1. Preparations :

To be made available are ...

- An erection crane with a load carrying capacity of about 1000 Kg and a crane hook height of

at least 4 m ( = 13 ft.) above the floor.

- Lifting ropes

- Dimension drawing, erection drawings, wiring and circuit diagrams.

- Torque wrench for a range of 6 - 100 NM.

- Circlip plier

- . Commercially available set of open end 8 ring spanners size from 7 mm. to 43 mm.

- Cleaning and working materials like cloths etc.

- Conducting grease

- Spirit level

4.2 Erection Procedure :

- Attach consignment unit breaker assembly with crane using the hooks (ref. Fig. 3 ).

- Place the support plate of the mvunting structure leg assembly on the prepared foundation.

Tighten the structure with the foundation bolts with specified hardware. (ref. fig. 1 )

- The exact location and the method of foundation can be obtained from the installation

layout plan or a general arrangement drawing. (Fig. 1 )

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4.2.1 Adjustment of control cubicle and spring mechanism cabinet.

The complete circuit breaker with control cabinet has adjustment provision to maintain a

maximum ground clearance upto 3860 mm in a slot of every 100 mm. Depending on the site

requirements of Incoming and Outgoing cable, the height of the pole terminals can be adjusted

suitably as shown in GA drawing.

- Once the height is adjusted, the fasteners shall be tightened to achieve the required ground

clearance & clearances between phases.

- Ensure the level of the breaker by spirit level.

4.3 High voltage connection : (Fig. 1 )

The high voltage connection fasteners shall be preferably of M 12 size stainless steel bolt and

nut and at least 1 washer and i spring washer.

Terminal connectors (Aa - Fig. 1 ) should be properly cleaned using SS Wire brush to remove

the aluminium oxide film and conducting grease to be applied.

The cable terminals shall be connected in such a fashion that the clearance are maintained

properly.

4.4 Low voltage connections :

The auxiliary circuit connection shall be checked as per the relevant schematic diagram for

correctness. (See fig. 2 for typical schematic). A removable gland plate is provided in the bottom

of control cable (Ls - Fig. 1 ) which can be suitably drilled as per control cable glands.

5. Commissioning

All the data / parameters which are checked or measured shall be entered in a commissioning

record and kept for later comparison. The final trial switching operations shall be carried out on

fully erected circuit breaker, isolated from the high voltage system and earthed according to the

regulations.

Once the auxiliary circuit is connected to the low voltage system, the spring charging motor get

a supply and the motor starts charging the spring. As the spring is charged completely,

automatically the motor supply will get cut off and the breaker is ready for closing operation.

The closing and opening operations, then can be performed as explained in paint 3.2.2 and

point 3.3.3..

Space Heaters :

One Space Heater is provided in the control cabinet. The heater switch must be always "ON",

when the breakers are in service to prevent condensation.

(5)

6. Checking the Vacuum

Before putting the breaker in service, or if any interrupter is suspected for leakage, vacuum

should be checked. The best way to check vacuum if to conduct high voltage test. ( 56kV,

1 Min.) Across the open contact of circuit breakers. If HV test kit is not available, then the

following procedure shall be followed.

1. Put the circuit breaker off.

2. Isolate the circuit breaker from high voltage connections.

3. Earth the circuit breaker.

4. Disconnect auxiliary supply.

5. Discharge the springs manually.

6. Visually inspect the circuit breaker and carry out further maintenance.

Remove the bottom covers & side covers of the duct ( Refer fig.l1 ) Remove the circlip from

the pin used for connecting the linkage system (links 6,7 and 8 ) of each pole. When the pin is

removed, the actuating rod will be suddenly pulled up due to the vacuum in the healthy

interrupter.

6.1 Dielectric Test :

Prior to commissioning the breaker or putting it back into service after a maintenance outage,

the circuit breaker should be checked for insulation resistance for following configurations

using a 5kV meggar kit.

1. CB open, between phase terminals (2 readings)

2. CB open, between top terminals and earth (3 readings) and

3. CB closed between terminals and earth (3 readings)

(6)

7. MAINTENANCE

7.1 Caution :

Before carrying out any maintenance work it is essential to follow the procedures given below :

· Open the circuit breaker and check that both opening and closing springs are discharged.

·

7.2 General features :

During normal service the circuit breaker require only limited maintenance. The frequency -

and the sort of inspection and maintenance basically depend on the service conditions.

Various factors must be taken into account e.g. frequency of operations, interrupted current

values and relative power factor as well as the installation ambient.

The following table gives the maintenance schedule showing the relative time intervals between

maintenance work. As far as the time interval between these operations is concerned, it is

advisable to comply with specification given in the table.

On the basis of the results obtained during the periodic inspection, it is possible to set the

optimal time limits for carrying out maintenance work.

These rules should also be followed :

Any circuit breaker which will only operate a few times or which will remain closed (ON) or open

(OFF) for long periods, should be operated from time to time to prevent clogging which may

cause a reduction in the closing or opening speed.

When the circuit breaker is in service it should be visually inspected to detect any dust, dirt or

damage of any kind.

7.3 Maintenance schedule :

Maintenance operations Installation in Instalplation in dusty or

normal ambient polluted ambient

Carry out tne general inspection One year Six months

(For details, refer clause 7.4)

Measure the insulation resistance Three years 1 year

Lubricate the sliding points 1 year 1 year

Carry out operating mechanism Five years or every Three years or every

maintenance 10,000 operations 5,000 operations

Complete overhaul Ten years or every Five years or every

10,000 operations 10,000 operations

Maintenance of operating mechanism Refer Section 8.2 Refer Section 8.2

(7)

7.4 . General inspection of the circuit breaker

Part subjected to Abnormalities noticed Remedies

1 ) Operating Mechanism Presence of dust on the Clean with a dry brush or cloth

mechanism

Distorted or oxidized springs Replace the damaged spring

Locking rings out of place, Refit the locking rings in their position

loose nuts or screws and tighten the nuts or screw suitably.

Wires and relative fasteners Replace the wires, fasteners and

detached reconnect the detached wire correctly.

2) . High voltage breaker pole Presence of dust or dirt on the Clean with a dry brush or cloth

part insulating parts.

Locking circlips out of place. Refit the locking circlips in their

Loose nuts or screws position and tighten the nuts or

screws

Distortion or cracking of the Ask ABB Nashik for replacement

of insulating parts the damaged parts.

Traces of overheating or loose Clean the connections and the

screws on the connections to breaker terminals with a rough rag

the circuit breaker terminals. soaked in a suitable solvent cover

them with neutral grease and tighten

the screws.

3. Earthing connection Traces of oxidation and/or Clean with a rough cloth soaked in a

loose nut suitable solvent. Tighten the earthing

connection fully and cover it with

neutral grease.

4. Auxiliary circuit supply Check the supply voltage of The releases and the electrical

voltage the operating mechanism interlocking devices must work

electrical accessories, correctly for values between 85%

and 110% of the relative rated

voltage.

5. Operating and control Carry out the functional tests. Replace the damaged or faulty

elements Loose hardware of control elements (If necessary ask ABB

elements. Nashik.) Tighten the hardwares of

control elements.

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8. Operating Mechanism

The operating mechanism has a spring charging device which can be operated by motor or by hand.

The operating device has compression spring for closing and tension springs for opening. The opening

spring is charged automatically when the breaker is closed . A closed breaker with charged closing

spring can be operated OPEN - CLOSE - OPEN without intermediate motorised or manual charging

and the breaker can therefore be used

for auto re-closing. Charging of the closing spring can be stopped by disconnecting the voltage to the

motor and manually operate the breaker CLOSE - OPEN.

An indication shows whether the closing spring is charged or not and the number of opening operations

are recorded on a counter.

The motor can be supplied via .a station battery, a network or via a transformer with a limit load of at

least 500 VA. The motor starts after each closing operation and charges the closing springs within 15

seconds.

The construction of the operating mechanism is shown in figure 4. The device has two shafts. The top

shaft (6) is connected to the breaker poles via links and is directly actuated by the openings springs (5).

The bottom shaft (3) is connected directly to the closing spring (11). These two shafts are linked via the

driving disc (9) and the link (12), and by the trip free device (14). The bottom shaft is also connected to

the charging device via the trip-free device (1 ) and the link (4).

The latching & trip free devices (1 )and (14) are of the same type that have been used in ABB

equipment since 1950 and have proven extremely reliable .

The motor operated unit consists of a toothed transmission gear with an eccentricity driven tooth wheel

as a last step. The operating device is also mounted with auxiliary contacts and trip coils.

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SPRING MECHANISM

SR.NO. ITEM DESCRIPTION PART NO.

1 & 2 Trip Free Device ( Bottom) IN 5436 0001 - A

3 Bottom Shaft IN 5439 0002 - D

Assembly.............................

5 Opening Spring................................... 1 VYN402850-001

6 Top Shaft Assembly 1VYN402801-AR

11 Closing Spring:................................... 1VYN402801-Z

12 Link..................................................... IN 2194 0001 - AE

9 & 14 Trip Free Device (Top)........................ IN 5436 0001 - B

OPERATING MECHANISM

SR.NO. ITEM DESCRIPTION PART NO.

1 Closing coil......................................... IN 5274 0001 - A*

2 Closing damping device..................... IN 5456 0711 - 4

3 Micro switch........................................ IN 5445 0744 - A

4 Tripping coil........................................ IN 5274 0001 - A*

5 Auxiliary contact................................. IN 5218 0004 - 1

6 Motor.................................................. IN 4461 0002 - E*

7 Counter.............................................. IN 5692 0501 - 2

* Please specify voltage

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8.1 Operating Mechanism Working Principle :

Fig 4 shows the operating device with the breaker in the open position .The closing spring

(1 1 ) is charged, if the latch (2) is tripped the bottom shaft (3) is released, its turning is transmitted

via link (12) to the mechanism top shaft (6)

Thus the circuit breaker is closed and at the same time the opening spring (5) has been charged.

Driving disc (9) comes to rest against stop (10). The energy of closing spring is transmitted via link (12)

and held by the trip - free device (14) which also prevents the opening spring turning the mechanism top

shaft (6). Now, the charging device starts and link (4) moves upwards until latch (2) is engaged. At this

point link (4) turns and begins to move downwards, whereupon the bottom shaft turns and retention.

Thus the closing spring position is reached.

During the breaker opening, latch is released, thus releasing the top shaft which via the insulating

links (7), actuates the moving contact of the breaker poles, for interruption. The spring (8) returns the

link (12) with the associated driving pin and the operating device to the position.

For rapid re-closing the associated control cabinet can be fitted with suitable relay equipment. The

VBF can be fitted with two opening coils and one closing coils.

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8.2 . Maintenance of Operating Mechanism

Maintenance Schedule

Sr Description Before Interval Interval Every 1000 No Start up of of Operations 1 Year 5 Years01 CHECKING OF OPERATING MECHANISM.

1.1 Checking of fastener tightness Fig. 5A - item B.H.L.BM.

1.2 Checking of shock absorbers for - leakage or stuck-up. Fig.5A item F&G.

1.3 Checking of top & bottom trip free mechanism, cap & coupling Fig.5A, Item J&K.

1.4 Closing & Tripping spring assembly & split pin (N) on them (Fig. 5A)

1.5 Bearing item (P) Fig. 5A

1.6 Checking of setting

Coupling & knife catch gap (Setting 1, Fig. 5B) Top TFM & CAP gap (Setting 2, Fig.5A) Both gaps should be between 1-2 mm)

1.7 Spring cut off micro switches.

02 LUBRICATION OF CHARGING DEVICE AND OPERATING GEAR

NOTE1 ) Complete overhaul of circuit breaker with replacement of pole parts to be done after 10,000 operations or 10 years, whichever is earlier.

2) Ask ABB for details of overhaul procedure.

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-

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-

-

-

-

-

-

-

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8.3 Replacement of Operating Coils

Refer. Fig.6 & 8 which Indicates the mounting arrangement for closing coil and the tripping coil and

auxiliary switch.

8.4 Replacement of Microswitch (Fig.7)

Microswitch is mounted on a circuit breaker frame and likely to get distributed. Theframe is

provided with slots vertically and the microswitch can be adjusted vertically. After the adjustment

of the microswitch, screws of the fixing bracket shall be fasten correctly.

8.5 Replacement of Motor

Refer. Fig.9. for replacement of motor. The figure is self explanatory. The motor is mounted on spring

charging device, with the help of screws.

8.6 Breaker Pole :

ABB 36kV Outdoor Circuit Breaker type VBF is developed using a well proven vacuum interrupters,

excellent arc quenching and insulating properties of vacuum offer long reliable service.

The construction of the pole of this breaker is very simple and has very less number of moving parts, so the

operating energy level is very low, thus requires a very low maintenance. However, assembly of a pole at site may

be required for replacement of vacuum interrupter.

Construction & Assembly of a Pole :

- Fig. No. 10 shows the complete assembly of a pole.

Assembly of pole can be done as follows :

The crank housing assembly consists of a crank housing (1 ). Clean and degrease the sealing surface

and sealing ring grooves. Mount damper and lock it (2) with a circlip. Now push the bearing (3) in the

bearing seat provided inside the crank housing. Fix the bearing (4) on the other side of crank housing.

Then insert a spacer (5). Insert the seal (6) duly with grease Syntheso PROAA2.

13

Then insert a spacer (7) and one more seal in the opposite direction as shown in fig. Insert the spacer

and press the bearing (4). Now insert the crank shaft (8) Match the serration's of crank shaft with the pole

lever (9) Push the shaft completely inside and tighten the bolt of the pole lever. Ensure that pole lever is

located correctly in the shaft. Then fix the spacer (10) and fix the circlip. Ensure the circlip

is properly expanded in the groove.

Ensure the free movement of crank inside the crank housing.

Connect the insulating rod assembly(11 ), with a pin (12) and special clip (13) The insulating rod assembly

is used to connect the pole lever with the actuating stud which is fixed to the moving contact of the

vacuum interrupter.

The insulating rod assembly consist of a cup assembly which contains a set of spring washers and

a actuating stud, which exerts a required contact pressure on the moving contact while the breaker is

closing.

Now, mount the porcelain insulation (14) with the crank housing assembly. Ensure that the 'O' ring is

properly located in a 'O'ring groove. Now take the lower terminal and ix the guide bush (15). Mount the

current collection hub (16) duly greased from inside (contact grease L3) on the lower terminal (17) and

tighten the bolts from bottom side. Now fix the lower terminal on the support insulator. Ensure the 'O'

rings are correctly located in the groove.

Take the interrupter (18) and fix the contact plug (19) on the moving contact of the interrupter. Fix the

guide ring (20) on the groove of the contact plug. The contact plug is specially designed and used for

holding the lamella contact (21 ) in the proper place. Apply a light coat of contact grease L3 on the lamella

contact. Then fix the actuating stud (22) with a special washer (23). Tighten the assembly with M10 hex.

nut and Belleville washer.

14

Caution :

While fixing the contact plug and actuating stud, vacuum interrupter shall be protected from twisting

movement, which may damage the sealing bellows of the vacuum interrupter.

Insert this interrupter assembly in the collector collection hub and match the hole of the actuating stud

and the insulating rod. Insert the special pin (24) and fix the split pin. Now mount the upper insulator

and fix it with the lower terminal plate. Fix the 'O' ring in the upper terminal and then locate the upper

terminal (24) on the insulator body. Secure the vacuum interrupter with the upper terminal and fix the

bolt. Before tightening the upper bolt take few manual operations by fixing the inter pole lever (27) for

R&B pole and for Y pole composite lever (28) .

Ensure the free movement of the contact and then tighten the bolt of vacuum interrupter with a torque

of 90 NM. Fix the sealing cover with a sealing 'O'ring and tighten the hardware. Fasten the hardware

of inter pole lever and composite lever. This completes the pole assembly.

15

FAULT FINDING CHART

FAULT CAUSE REMEDY

Spring does not get Motor has wrong or no Measure voltage on the charged operating voltage motor leads

Motor shaft broken Change motor Motor gear damage Change motor The latch for the tripping Check mechanism device does not function

Disconnection in the wires Check by measuring Micro-switch arm wrongly Adjust the micro switch adjusted operating arm

Closing of breaker does not Operating coil does not Measure the voltage adjust take place although there is operate the coils adjustment screw. an indication that the Check the breaker springs. springs are charged

Breaker closes then opens The toggle joint of the Adjusts the toggle joint again mechanism are incorrectly adjusted

Main circuit is wrong Check the wiring as per schematic drawing

Wrongly adjusted clearance Adjust the opening magnet. of opening magnets armature

Breaker continuously opens Anti-pumping relay wrong Change relay and closes or faulty.

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LIST OF DRAWINGS

Fig. 1 : Circuit Breaker GA Drawing

Fig. 2 : Schematic circuit diagram.

Fig. 3 : Lifting of Breaker

Fig. 4 : Operating Principle of Circuit Breaker

Fig. 5 : Maintenance of Mechanism Fig.5A / 5B

Fig. 6 : Replacement of tripping coil

Fig. 7 : Replacement of microswitch

Fig.8 : Replacement of closing coil

Fig. 9 : Replacement of motor

Fig. 10 : Breaker Pole Assembly

Fig. 11 : Breaker Assembly

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No liability is accepted for the accuracy of the information contained in this publication. We reserve the right to make amendments in the courseof technical progress.

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Asea Brown Boveri LimitedPlot No 79, Street No 17MIDC Estate, SatpurNashik - 422 007Telephone: (0253) - 351095/96/97/98 : (0253) - 351261/62/63/64Telex : (0752) -288/389 ABBN INTelefax : (1253) - 350644 / 351249Gram : ABBFILIAL