MR BA_VV_Ex_en

On-load tap-changer VACUTAP® V V-EXOperating Instructions BA273/02

www.reinhausen.com

NOTE

Changes may have been made to a product after going to press with this documentation.

We expressly reserve the right to make changes to a product’s technical data and design as well as changes tothe scope of delivery.

In all cases, the information submitted and agreements concluded during processing of the quotation and orderin question shall be binding.

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BA 273/02 - VACUTAP® V V-ExThe copying, distribution and utilization of this document as well as the communication of its contents to others without

expressed authorization is prohibited. Offenders will be held liable for the payment of damages. All rights reserved in the eventof the grant of a patent, utility model or ornamental design registration. ©Maschinenfabrik Reinhausen GmbH 2007

Contents

Contents

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

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

1.2 Specified application ................................................................................................................................................... 5

2 Design / Types ............................................................................................................................................................................ 6

3 Standards and regulations for explosion-proof on-load tap-changers ........................................................... 7

3.1 Basic principles .............................................................................................................................................................. 7

3.2 Explosion protection types ........................................................................................................................................ 8

4 Measures for ensuring compliance with explosion protection requirements ................................................ 8

4.1 Oil quality for explosion-proof on-load tap-changers ..................................................................................... 8

4.2 Oil quality for the explosion-proof transformer ................................................................................................ 8

4.3 Maximum surface temperature (DIN 60079-0 after 5.3) ................................................................................ 8

5 Installation instructions ........................................................................................................................................................ 9

5.1 On-load tap-changer oil system ................................................................................................................................ 9

5.2 On-load tap-changer oil system equipment .......................................................................................................... 10

5.3 Insulating oil .................................................................................................................................................................... 10

5.4 Level control .................................................................................................................................................................... 10

5.5 Dehydrating breather .................................................................................................................................................... 10

5.6 Oil conservator ................................................................................................................................................................ 10

5.7 Level indicator ................................................................................................................................................................. 10

5.8 Monitoring of the protective fluid level ................................................................................................................. 10

6 Shipment ..................................................................................................................................................................................... 11

7 Installing the on-load tap-changer for cover mounting .......................................................................................... 13

7.1 Mounting flange ............................................................................................................................................................. 13

7.2 Attaching the on-load tap-changer to the transformer tank .......................................................................... 13

8 Installing the on-load tap-changer in a transformer with bell-type cover ..................................................... 15

8.1 Installing the on-load tap-changer in the supporting structure .................................................................... 15

8.2 Preparation ....................................................................................................................................................................... 16

8.3 Separating the top part of the on-load tap-changer head from the bottom part ................................... 16

8.4 Attaching the bell-type cover .................................................................................................................................... 17

9 Connecting the tap winding and the tap-changer take-off terminal ............................................................... 17

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Contents

10 Transformer ratio test .............................................................................................................................................................. 18

11 Drying process and oil filling ................................................................................................................................................ 18

11.1 Drying process ................................................................................................................................................................. 1811.1.1 Vacuum-drying .................................................................................................................................................. 18

11.1.1.1 Vacuum-drying in the autoclave ................................................................................................ 1811.1.1.2 Vacuum-drying in the transformer tank .................................................................................. 19

11.1.2 Vapour-phase drying ....................................................................................................................................... 1911.1.2.1 Vapour-phase drying in the autoclave ...................................................................................... 1911.1.2.2 Vapour-phase drying in the transformer tank ........................................................................ 19

11.1.3 Operating the on-load tap-changer ........................................................................................................... 20

11.2 Oil filling ........................................................................................................................................................................... 20

12 Pipe connections ........................................................................................................................................................................ 20

12.1 Pipe connection R for protective relay RS 2001-Ex ............................................................................................ 20

12.2 Pipe connections S and R (connection Q specially designed)Connection to tap-changer interior ......................................................................................................................... 20

12.3 Connection E2 ................................................................................................................................................................. 21

13 Mounting the motor drive, bevel gear and drive shaft ............................................................................................. 21

13.1 Mounting the motor-drive unit (see appendix, drawing 898743) .................................................................. 21

13.2 Mounting the bevel gear ............................................................................................................................................. 21

13.3 Mounting the drive shaft (square tube) .................................................................................................................. 21

14 Commissioning the on-load tap-changer at the transformer manufacturer's site ...................................... 22

14.1 Operational tests ............................................................................................................................................................. 22

14.2 Complete oil filling ........................................................................................................................................................ 23

14.3 Ground connections ...................................................................................................................................................... 23

14.4 Electrical tests on the transformer ............................................................................................................................ 23

15 Transport to the operating site ............................................................................................................................................ 24

16 Commissioning at the operating site ................................................................................................................................ 24

17 Monitoring during service ...................................................................................................................................................... 25

18 Failures ........................................................................................................................................................................................... 25

19 Maintenance ................................................................................................................................................................................ 26

20 Appendix ........................................................................................................................................................................................ 27

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1 General

1.1 Safety Instructions

All personnel involved in installing, commissioning, operating,maintenance or repair of the equipment must:

- be suitably qualified 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

user and- a reduction in the efficiency of the equipment.

Safety instructions in this manual are presented inthree different forms to emphasize important information.

WARNING

This information indicates particular danger to life andhealth. Disregarding such a warning can lead to serious orfatal injury.

CAUTION

This information indicates particular danger to theequipment or other property of the user. Serious or fatalinjury cannot be excluded.

NOTE

Notes give important information on specific subjects.

CAUTION

The on-load tap-changer may only be used with the trans-former specified in the order.Installation, electrical connection and commissioning ofthe on-load tap-changer must only be carried out byqualified, skilled personnel and only in accordance withthese Operating Instructions.

It is the responsibility of the user to ensure that the on-load tap-changer is used for the specified application only.For safety reasons, any unauthorised work such as installa-tion, alteration, electrical connection, commissioning ormodification to the on-load tap-changer equipment isforbidden without first consulting MR!

The trouble-free operation of the drive, on-load tap-changer and transformer may be put at risk.

1 General

1.2 Specified application

WARNING

All relevant fire protection regulations must be strictlyobserved.

Operation of the VACUTAP® VV-EX is always permitted withinthe entire temperature range covered by IEC 60214-1.The properties required by MR for the types of oil to be usedmust always be adhered to under all circumstances.

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1

2 Design/Types

The on-load tap-changer VACUTAP® V V-Ex (fig. 1) is con-structed as an on-load tap-changer of tubular design.It combines the functions of a diverter switch unit and a tapselector.The on-load tap-changer is attached to the transformer coverby the tap-changer head.Where required, the on-load tap-changer is equipped with achange-over selector.The design and designation of the main components of theon-load tap-changer can be found in the installation drawings(see appendix, drawing 898864).The on-load tap-changer designs V V-Ex without a change-over selector are available with a maximum of 12 operatingpositions. Designs with a change-over selector have a max. of23 operating positions.These Operating Instructions apply to the following on-loadtap-changer designs (each with or without a change-overselector):

Three-phase tap-changers:V V III 250 Y-Ex, V V III 400 Y-Ex, V V III 600 Y-ExV V III 250 ∆-Ex, V V III 400 ∆-Ex, V V III 600 D-Ex

2 Design/Types

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3 Standards and regulations for explosion-proof on-load tap-changers

3 Standards and regulations for explosion-proof on-load tap-changers

3.1 Basic principles

All VV-Ex on-load tap-changers from the MR product rangeare certified for II 3G EEx nAC II T3.

Equipment in this category is intended for use in areas in which explosive atmospherescaused by mixtures of air and gases, vapors or mists or by air/dust mixtures are presentcontinuously, for long periods or frequently.

Equipment in this category is intended for use in areas in which explosive atmospherescaused by gases, vapors, mists or air/dust mixtures are likely to occur.

Equipment in this category is intended for use in areas in which explosive atmospherescaused by gases, vapors, mists, or air/dust mixtures are unlikely to occur or, if they do occur,are likely to do so only infrequently and for a short period only.

for g

ases

for p

owde

r

Definition

1G(0)

2G(1)

3G(2)

1D(20)

2D(21)

3D(22)

Equipment category / zone classification

Equipment in this category is intended for use in underground parts of mines as well as those parts of surface installations of such minesendangered by firedamp and/or combustible dust.

Equipment in this category is intended for use in other areas in which explosive atmospheres may be present.

Equipment groups

I

II

!!

Temperature class

Explosion group

Protection type

Explosion-proof equipmentEquipment category

Equipment group

Sign for explosionprotection

!

d flameproof enclosuree increased safetyl intrinsic safety (la, lb)

m encapsulationo oil immersionp pressurized apparatusq powder filling

n protection type „n“ (only zone 2)

n A: non-sparking apparatusn C: sparking apparatus with special

protection of contactsn R: restricted breathing enclosuresn L: energy-limited equipmentn P: equipment with simplified

n-pressurization

Protection types

Temperature Max. equipment Ignition temperatureclass surface temperature of the inflammable

substances

T1 450 °C > 450 °C

T2 300 °C > 300 °C < 450 °C

T3 200 °C > 200 °C < 300 °C

T4 135 °C > 135 °C < 200 °C

T5 100 °C > 100 °C < 135 °C

T6 85 °C > 85 °C < 100 °C

Gases, vapors Min. ignition EN/IEC(examples) energy

(mJ)

- ammonia -- IIA

- acetone, methane, ether, petrol, benzene,diesel, petroleum, acetic acid, fuel oil, hexane,methane, propane

- ethylene, isoprene, town gas 0.06 IIB

- hydrogen, acetylene, carbon disulfide 0.02 IIC

Explosion group Temperature classes

!

II 3G EEx nAC II T3

!

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3 Standards and regulations for explosion-proof on-load tap-changers4 Measures for ensuring compliance with explosion protection requirements

4 Measures for ensuring compliancewith explosion protection require-ments

For certification of the on-load tap-changer for application inareas subject to explosion hazard, explosion protection class"nAC" according to the harmonized EN 60079-15 standard isused.

4.1 Oil quality for explosion-proof on-load tap-changers

The quality of the insulating oil in the diverter switch oilcompartment that is required according to IEC 60296 isensured through compliance with the thermal applicationcriteria specified in IEC 60214, and through application ofvacuum cells in transition circuits.

4.2 Oil quality for the explosion-proof transformer

During switching operations, sparks (low energy) may begenerated at the tap selector of the on-load tap-changer inthe transformer oil chamber.Sections 5.1.6 and 5.1.7 of the IEC 60214 on-load tap-changer standard must be followed.

CAUTION

The oil quality and the dielectric strength must be checkedregularly.

The service intervals (oil change) must be complied with.

For certain on-load tap changer types (see OperatingInstructions no. 18, oil filter plant) an MR oil filter plant isused.

4.3 Maximum surface temperature (DIN 60079-0after 5.3)

During each switching operation additional heat is transferredto the oil. The heat originates from the transition resis-tors. Theswitch-off value of the temperature sensor is set such that thetemperature of the warmest oil layers in tap-changer oilcompartment does not exceed +130 °C. Temperaturemonitoring in the on-load tap-changer cover prevents furtherswitching operations of the on-load tap-changer, thuspreventing an additional temperature rise of the insulating oilin the on-load tap-changer. This ensures that the surfacetemperature at the on-load tap-changer, the protective relayand the oil filter plant does not exceed 130°C duringoperation.

For each order, the set value of the temperature sensor isspecified individually for all explosion-proof on-load tapchanger types.

CAUTION

The set value of the temperature monitoring system is setin the factory. This value must not be changed.

3.2 Explosion protection types

The following standards and regulations apply to explosion-proof on-load tap-changers:

• Protection type "nAC" according to EN 60079-15 forsparking equipment with suitably protected contacts(except restricted breathing enclosures, energy-limitedcircuits or pressurized apparatus).

• Supplementary requirements apply to:

vacuum interrupters- hermetically sealed equipment that generates arcs,

sparks or hot surfaces

the on-load tap-changer oil compartment- sealed or enclosed equipment that generates arcs,sparks or hot surfaces

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5 Installation instructions


5.1 On-load tap-changer oil system

The oil system of the on-load tap-changer consists of an oilconservator, a protective relay and an on-load tap-changeroil compartment.

The required oil level in the on-load tap-changer oil system ismaintained through the measures described in sections 5.2 to5.8.

2

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CAUTION

The explosion-proof on-load tap-changer must only beoperated in conjunction with an explosion-proof protectiverelay (fig. 2; no. 2).


5.2 On-load tap-changer oil system equipment

The explosion-proof on-load tap-changer must only beoperated in conjunction with an explosion-proof protectiverelay.

5.5 Dehydrating breather

A dehydrating breather [6] (see fig. 2) with oil barrierprevents water, impurities, insects etc. from entering theinsulating oil.

5.6 Oil conservator

The oil conservator [5] (see fig. 2) ensures that all oil systempiping of the on-load tap-changer is always filled with insu-lating oil during the operation (when temperature changes ofthe insulating oil occur).

5.7 Level indicator

A level indicator [3] (see fig. 2) enables the level of theprotective fluid to be monitored during operation.The maximum and minimum level of the protective fluidmust be clearly identified.

5.8 Monitoring of the protective fluid level

Monitoring of the protective fluid level [4] (see fig. 2) in theoil conservator ensures that during the specified operationthe oil system piping of the on-load tap-changer is alwaysfilled with insulating oil.The minimum permissible protective fluid level is in the oilconservator. The protective fluid level must be monitoredcontinuously at the oil conservator during operation via alimit value contact or limit value contacts (if prior warning isrequired).

5.3 Insulating oil

MR on-load tap-changers, protective relays and associated oilfilter plants must only be operated with insulating oil accord-ing to IEC 60296 and IEC 60422. This requirement is currentlyspecified in the Technical Data / General Part / Section 2.16(and noted in the operating instructions for the explosion-proof on-load tap-changer and the explosion-proof protec-tive relay).

5.4 Level control

The explosion-proof on-load tap-changer must only beoperated in conjunction with an oil conservator with levelcontroller. Using a suitable oil system, the oil conservator orthe fittings and the pipes must ensure the oil level in the on-load tap-changer oil conservator.The customer is responsible for the installation of the oilconservator and all associated piping. It is not part of MR’sscope of delivery.

CAUTION

Any existing stop valves may not be allowed to affect levelregulation.

CAUTION

If the oil level falls below the lowest permissible protectivefluid level, the transformer must be turned off.

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6 Shipment

6 Shipment

On-load tap-changer and motor-drive unit are shipped in theadjustment position.

The on-load tap-changer equipment is shipped as follows:(insulating parts are protected against moisture):

On-load tap-changer VACUTAP® V V-Ex

V V III 250/400/600/40 kV, with change-over selector,(ca. 240 kg),V V III 250/400/600//76 kV, with change-over selector,(ca. 255 kg),V V III 250/400/145 kV, with change-over selector,(ca. 280 kg), fig.3

3

TAPMOTION® ED-Ex 100 S-Ex (ca. 80 kg), orTAPMOTION® ED-Ex 100 L-Ex (ca. 130 kg), fig. 4.

Drive shafts with coupling parts and bevel gear(max. ca. 20 kg), fig. 5.

Protective relay RS 2001-Ex (3.5 kg), fig. 6.

The shipment should be checked against the consignmentdocuments to ensure it is complete. The parts must be storedin a dry place until assembly.

The on-load tap-changer must remain packed air-tight in theprotective wrapping and should only be removed shortlybefore installation.

NOTE

In general, the drive shafts, the bevel gear and theprotective relay are packed with the on-load tap-changer.

WARNING

When carrying out any work on the on-load tap-changer,motor-drive or components, ensure they are positionedsecurely.Otherwise there is a danger that individual devices may tipover accidentally. This can result in serious injury and, insome cases, fatalities.

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6 Shipment

4 898743

6

MRMR

5 726140

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7 Installing the on-load tap-changer for cover mounting

plan

CAUTION

When attaching the on-load tap-changer, ensure that thelifting device uses 4 cables of equal length, at least 1m (seeappendix, drawing 898866), otherwise the equipment maybe damaged.

164M005

CAUTION

Under all circumstances, avoid dropping parts into the oilcompartment, as there is a risk that the on-load tap-changer will be blocked.This could damage the on-load tap-changer and the trans-former.For this reason, check the quantities of small parts whendisassembling and reassembling to ensure they are identical.

7

r


int013

8

7.1 Mounting flange

A mounting flange is required for mounting the tap- changerhead to the transformer cover. This mounting flange shouldbe designed according to the sealing surface of the tap-changer head (see fig. 7 and fig. 8 and appendix, drawing898866).

We recommend using a template to position the studs (M12,max. length 45mm), see fig. 9 and appendix, drawing893787. This template is supplied free of charge for the initialinstallation of an on-load tap-changer VACUTAP® V V-Ex, ifdesired.

7.2 Attaching the on-load tap-changer to thetransformer cover

Proceed as follows to attach the on-load tap-changer:

1. Remove the tap-changer cover (fig. 10)• Loosen the 24 bolts M10 x 35/w.s.17,

remove the 24 locking washers.• Remove the tap-changer head paying attention

to the sealing (fig. 11).

2. Loosen the fixing screws in the top part of the head(22 hexagonal screws M8/w.s.13, locking washers forsecuring, fig. 12).

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3. Separate the top part of the head from the bottompart• Lift up the top part of the head. Take care not

to damage the O-ring gasket on the bottompart of the head (fig. 13).

4. Clean the sealing surface on the mounting flange andon the tap-changer head.

5. Place an oil-resistant gasket on the mounting flange.

6. Place upper part of the tap-changer head over thestud bolts of the mounting flange – do not tighten!

7. Check the position of the tap-changer head when it isinstalled. The on-load tap-changer can be turned to-wards the top part of the head in steps of 15 degrees.

8. Slowly lift the on-load tap-changer from underneathtowards the top part of the head using 4 cables ofequal length (min. 1m), (see appendix, drawing898866).Pay attention to the centering bolts.

9. Screw the top and bottom part of the head together• 22 hexagonal screws M8/w.s.13

(tightening torque 20 Nm).

10. Attach upper part of the tap-changer head to themounting flange.

11. Fix the tap-changer cover• 24 bolts M10 x 35/w.s.17 (max. torque 34 Nm),

24 locking washers.

int0149

10

11

r

164M009

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8 Installing the on-load tap-changer in a transformer with bell-type cover


To install the on-load tap-changer in a transformer with abell-type cover, the on-load tap-changer must be mountedonto a supporting structure. For this purpose, the bottompart of the tap-changer head is designed as a supportingflange (see appendix, drawing 899110).

Firstly, lift the on-load tap-changer into the supportingstructure and connect it to the tap winding. The on-load tap-changer must be attached to the supporting structure in sucha way so it cannot be displaced.

The supporting flange is provided with drill holes, so it can befixed to the supporting structure easily. Placing spacer blocksbetween the supporting structure and the supporting flangetemporarily may be of help. These are to be removed beforeattaching the bell-type cover.

Once the bell-type cover is attached, lift the on-load tap-changer with the lifting device (see appendix, drawing899110) and fix it to the bell-type cover together with thetop part of the head.

To attach the tap-changer head to the bell-type cover, werecommend using a mounting flange as described in section7.1.

NOTE

Due to the supporting structure, the diverter switch withan external change-over selector is limited in its installa-tion position. The supporting structure and the change-over selector including the activation lever must not collide(see appendix, drawing 899409).

The transformer ratio test and drying process are to becarried out according to sections 10 and 11.

CAUTION

Make sure that the connected leads do not exert any forceon the on-load tap-changer.In addition, there should be sufficient slack so that the on-load tap-changer can be raised to its final installationposition after the bell-type cover is attached.

8.1 Installing the on-load tap-changer inthe supporting structure

Lift the on-load tap-changer into the supporting structure.Check the installation position of the tap-changer and fix itsecurely.

By using the temporary spacer blocks between the supportingstructure and the supporting flange, the on-load tap-changeris at the correct final installation height after the bell-typecover is attached.This means the leads to be connected to the on-load tap-changer are correctly dimensioned in length.Connect the tap winding and the tap-changer lead accordingto section 9.

CAUTION

When attaching the on-load tap-changer, ensure that thelifting device uses 4 cables of equal length, at least 1m (seeappendix, drawing 899110), otherwise the equipment maybe damaged.

NOTE

The on-load tap-changer must be suspended exactlyvertical in the supporting structure.The on-load tap changer must be installed, so it cannot belifted by more than 5-20 mm after the bell-type cover isattached.

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rr

164M008 728070012 13

8.3 Separating the top part of the on-loadtap-changer head from the bottom part

Proceed as follows to attach the on-load tap-changer:

1. Remove tap-changer cover (fig. 10)• loosen the 24 bolts M10 x 35/w.s.17,

remove the 24 locking washers.• lift off the tap-changer cover. Take care not todamage the sealing (fig. 11).

2. Loosen the fixing screws in the top part of the head(22 hexagonal screws M8/w.s.13, locking washers forsecuring, fig. 12).Keep the loose parts for reinstallation.

3. Separate the top part of the head from the bottom part;• Lift up the top part of the head from the bottom

part. Take care not to damage the O-ring gasket onthe bottom part of the head (fig. 13).

8.2 Preparation

Before attaching the bell-type cover, the top part of the headmust be separated from the bottom part of the head (see 8.3).

Make sure the on-load tap-changer is in the adjustmentposition. This position is given in the connection diagramsupplied with the on-load tap-changer.

CAUTION

Under all circumstances, avoid dropping parts into the oilcompartment, as there is a risk that the on-load tap-changer will block.This could damage the on-load tap-changer and thetransformer.For this reason, check the quantities of small parts whendisassembling and reassembling to ensure they are identical.

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8 Installing the on-load tap-changer in a transformer with bell-type cover9 Connecting the tap winding and the tap-changer take-off terminal

8.4 Attaching the bell-type cover

1. Before attaching the bell-type cover, clean the sealingsurface of the bottom part of the head. Remove thespacer blocks (see section 8.1).

2. Lift the bell-type cover over the active part of thetransformer.

3. Before mounting the tap-changer head clean the sealingsurfaces on the mounting flange of the transformer.Place an oil-resistant gasket on the mounting flange.Depending on the height adjustment, there must be aclearance of 5 - 20 mm between the top part of the headand the bottom part. The position of the fixingholes in the top part of the head must align with theposition of the threaded holes in the bottom part of thehead. The on-load tap-changer can be turnedtowards the top part of the tap-changer head in stepsof 15 degrees.

4. Place upper part of the tap-changer head over the studbolts of the mounting flange – do not tighten!

5. Check the position of the tap-changer head when it isinstalled. The on-load tap-changer can be turned towardsthe top part of the head in steps of 15 degrees.

6. Using the lifting device, lift the on-load tap-changer to aposition (see appendix, drawing 899110) so that thebottom part of the head is aligned with the top part ofthe head and the connection screws of the top part andbottom part of the head (22 hexagonal screws M8/w.s.13and locking washers for safety) can be screwed in. Payattention to the centering bolts.

7. Screw the top part of the head and the bottom parttogether:

• 22 hexagonal screws M8/w.s.13(20 Nm tightening torque)

8. Attach upper part of the tap-changer head to themounting flange.

9. Fix the tap-changer head

• 24 bolts M10 x 35/w.s.17 (max. torque 34 Nm)• 24 locking washers

CAUTION

Under no circumstances should the on-load tap- changerbe lifted up with the fixing screws as this can damage thetop part of the head.

The tap winding and the tap-changer take-off terminal mustbe connected according to the connection diagram suppliedwith the tap-changer equipment.

If connection leads have to cross the open surface of the oilcompartment, there must be a clearance of at least 50 mmbetween the lead and the surface.

The designation of the tap-changer connecting terminals areshown in the connection diagram. They are provided withvertical drill holes, 11mm diameter for M10 bolts (seeappendix, drawing 898864).

9 Connecting the tap winding andthe tap-changer take-off terminal

CAUTION

Make sure that all connections are correctly and securelymade. The connection leads must be connected withoutexerting force on the on-load tap-changer.

CAUTION

The connecting terminals must not be twisted as this willjeopardise the functioning of the on-load tap-changer.

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11.1 Drying process

A precondition of MR's guaranteed dielectric values of theon-load tap-changer is that a minimum drying process mustbe carried out according to the instructions below (either11.1.1 or 11.1.2).

11.1.1 Vacuum-drying

11.1.1.1 Vacuum-drying in the autoclave

Heating:Heat the on-load tap-changer in air at atmospheric pressure,increasing the temperature by approx. 20 °C/h up to a max.temperature of 110 °C.

Pre-drying:Pre-dry the on-load tap-changer in circulating air at a max.temperature of 110°C for 10 hours.

10 Transformer ratio test11 Drying process and oil filling

Drying:Vacuum-dry the on-load tap-changer at a max. temperatureof 110 °C. The duration of the drying process depends on thatof the transformer.

14

NOTE

Before drying the transformer in the autoclave, the on-loadtap-changer cover must be removed and stored outside theautoclave.

KHW1139-4

E

bN

11 Drying process and oil filling10 Transformer ratio test

It is recommended that a transformer ratio test be carried outbefore the transformer undergoes drying.

To operate the drive shaft of the tap-changer head, a pipe(nominal width 25mm) with screwed-in coupling bolts(diameter 12mm) and a hand wheel or hand crank can beused.

16.5 drive shaft revolutions are required for one tap changeoperation. You should be able to hear the switching action ofthe on-load tap-changer clearly.

When operating the change-over selector (adjustment posi-tion ± 1 tap position), noticeable by the increased expendi-ture of force, the tap-change operation already under waymust always be completed without changing the rotationdirection.

Keep the number of tap-change operations without oil to aminimum.

The end positions, which are given in the connection diagramsupplied with the equipment (position designation), mustnever be overrun. To ensure this, always check the operatingposition reached through the inspection window on the tap-changer head (fig. 14).

After the transformer ratio test, the on-load tap-changermust be operated back to the adjustment position (seeconnection diagram supplied with the on-load tap-changer).

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11.1.1.2 Vacuum-drying in the transformer tank

The tap-changer head cover is vacuum-proof.

To ensure the interior of the oil compartment and the built-intap changer insert is sufficiently dried, a short connectingpipe with a nominal width of 25mm must be inserted bet-ween the transformer tank and a connecting flange on thetap-changer head which leads directly to the interior of theoil compartment.

The connecting pipe should be fitted on the tap-changerhead between the connections E2 and Q or E2 and R (for theposition of the connections see fig. 16 and section 12).

Details on the procedure, temperature and duration of thedrying process are described in section 11.1.1.1.

11.1.2 Vapour-phase drying

Before the drying process, the kerosene drain plug screw inthe oil compartment bottom must be opened to drain thecondensate.

The kerosene drain plug screw can be opened from outside(w.s.24) or from the inside (hexagonal recess screw w. s.8), (seefig. 15). The plug cannot be lost as it is attached. It must beclosed again after the drying process (torque 39 Nm).

11 Drying process and oil filling

11.1.2.1 Vapour-phase drying in the autoclave

Heating:Supply kerosene vapour at a temperature of approx. 90°C.Keep this temperature constant for approx. 3-4 hours.

Drying:Increase the kerosene vapour temperature applied to the on-load tap-changer by approx.10 °C/h to the desired finaltemperature which should not exceed 125 °C.The duration of the drying process depends on that of thetransformer.Check that the kerosene drain plug screw is closed after thedrying procedure.

CAUTION

Ensure the kerosene drain plug screw is securely closedafter the drying process to avoid oil from the oil compart-ment getting into the oil chamber of the transformer tank.

164M013

NOTE

Before drying the transformer in the autoclave, the tap-changer cover must be removed and stored outside theautoclave.

15

r

NOTE

If the transformer is to be dried in its own tank, the interiorof the on-load tap-changer must be connected to thevacuum by a connecting pipe, as the tap-changer headcover remains closed for the entire drying process.

11.1.2.2 Vapour-phase drying in the transformer tank

For vapour-phase drying in the transformer tank, the tap-changer insert must be removed to unscrew the kerosenedrain plug from inside the oil compartment (fig. 15).Please contact MR for specific instructions on removing andre-installing the tap-changer insert.

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12 Pipe connections

11 Drying process and oil filling12 Pipe connections

CAUTION

The oil compartment and its associated oil conservatormust only be filled with new insulating oil for transformersaccording to IEC 60296 (Specification for unused mineralinsulating oils for transformers and switchgear) andIEC 60422 (Supervision and maintenance guide for mineralinsulating oils in electrical equipment). For dielectricstrength limit values see section 19, table 1. The use ofany other oils may put the trouble-free operation of theon-load tap-changer and the transformer at risk.

11.1.3 Operating the on-load tap-changer

11.2 Oil filling

Close the tap-changer head by lowering the cover. Tighten all24 bolts M10/ w.s.17 on the cover uniformly (torque 34 Nm).

To fill with oil, use the connection S or R on the tap-changerhead. To apply a vacuum to the transformer and oil compart-ment simultaneously, install a connection pipe between theconnection E2 and R or S.

CAUTION

Do not operate the on-load tap-changer after dryingwithout a complete oil filling of the oil compartment, asbearings and gaskets will be damaged.The external change-over selector must also be wetted withoil after the kerosene drying, when switching occurs.

CAUTION

Under vacuum, fill the on-load tap-changer andtransformer simultaneously with new transformer oil.

There are 2 pipe connections provided on the tap-changerhead for different purposes.All pipe connections can swivel freely by loosening the thrustcollar (4 bolts M10/w.s.17), see fig.16 and appendix, drawing898863.

12.1 Pipe connection R for the protective relayRS 2001-Ex

Install the protective relay RS 2001-Ex (see appendix, drawing723653) according to our Operating Instructions no. 272 forprotective relay RS 2001-Ex.

12.2 Pipe connections S and R (Connection Q asspecial design)Connection to tap-changer interior

To lower the oil level during maintenance (approx. 7 l), apipe connection should be fitted to one of the freeconnections R, S or Q which ends at the side of thetransformer tank at operating height for a drainage tap.

NOTE

The stamped serial number must match the serial numberof the on-load tap-changer.

The protective relay must be installed directly on the tap-changer head in a horizontal position.

The arrow on the installed protective relay must point tothe oil conservator.

The pipe leading to the oil conservator must have aninclination of at least 2 %.

Ensure that the maximum space between the transformercover and the top edge of the tap-changer oil conservatordoes not exceed 5 m.

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164M014

16

12 Pipe connections13 Mounting the motor-drive unit, bevel gear and drive shaft

12.3 Connection E2

This connection is closed by a dummy plug. It leads into theoil chamber of the transformer, directly under the tap-changer head. When necessary, it can be connected to acollective pipe for the Buchholz-relay.

13.2 Mounting the bevel gear

The bevel gear is attached to a support on the transformercover with 2 screws (drill holes 18 mm, see appendix, drawing892916).

13 Mounting the motor-drive unit,bevel gear and drive shaft

NOTE

The serial number of the motor-drive unit must match thatof the on-load tap-changer (name plate).The motor-drive unit must be in the same operating posi-tion as the on-load tap-changer when coupling.The adjustment position is given in the connection diagramsupplied with the on-load tap-changer.

The motor-drive unit must be mounted at the providedplace on the transformer tank in a vertical position andprotected against transformer vibrations.

13.1 Mounting the motor-drive unit(see appendix, drawing 898743)

Detailed mounting instructions can be found in our Opera-ting Instructions no. 271 for the TAPMOTION® ED-Ex.

NOTE

The stamped serial number must match that of the on-loadtap-changer.

The horizontal drive shaft must align with the shaft end ofthe tap-changer head.

By loosening the thrust collar (6 screws M8/w.s. 13) theupper gear unit can swivel freely. After mounting, tightenthe thrust collar, (torque 15 Nm).

The bolts are to be secured.The above instructions also apply to bevel gears of specialdesigns and to intermediate bearings of the vertical andhorizontal drive shafts.

13.3 Mounting the drive shaft (square tube)

The drive shaft must be mounted according to our OperatingInstructions no. Nr. 276 for drive shaft-Ex.

The drive shaft is the mechanical connection between themotor-drive unit and the tap-changer head.

The bevel gear is responsible for changing the direction fromvertical to horizontal.

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13 Mounting the motor-drive unit, bevel gear and drive shaft14 Commissioning the OLTC at the transformer manufacturer's site

Accordingly, the vertical drive shaft must be installedbetween the motor-drive unit and the bevel gear, and thehorizontal drive shaft between the bevel gear and the tap-changer head.

The drive shaft is designed as a square tube and is connectedon both ends to the end of the drive shaft or driven shaft ofthe respective unit by two coupling brackets and onecoupling bolt.

Square tubes, coupling brackets, coupling bolts and screwsare corrosion-resistant.

The guard plate, which serves as a foot step protection forthe horizontal drive shaft over the transformer cover, and thesquare tubes are supplied in oversized lengths (variousstandard lengths). These parts must be cut to the required sizebefore mounting.

Before coupling the upper gear unit of the tap-changer head,operate the on-load tap-changer to the exact adjustmentposition (including idling) as follows:

Loosen the screws on the tap-changer head cover (24 boltsM10/w.s. 17, locking washers), raise the tap-changer cover atleast 15 mm so that the upper gear unit disengages.Support the tap-changer cover using suitable pieces of woodor similar.

Turn the upper gear unit of the tap-changer cover in thedesired direction so the drive shaft can be properly coupled.

Check the position of the driven shaft on the output side ofthe gear unit below the tap-changer cover and turn the driveshaft manually until the driven shaft engages into thecoupling of the gear unit.

Remove the supporting pieces of wood and fix the tap-chan-ger cover again, 24 bolts M10/w.s. 17, max. torque 34 Nm,locking washers for securing.

Finally, check the idling torque of the motor-drive unitagainst the diverter switch operation of the tap-changeraccording to our Operating Instructions no. 271 for themotor-drive unit ED-Ex.

NOTE

When installing the drive shaft, make sure that the shaftends to be connected are exactly aligned and the couplingbolts are greased.

14 Commissioning the on-load tap-changer at the transformermanufacturer's site

14.1 Operational tests

Before voltage is applied to the transformer, test tap changeoperations must be performed to check the mechanicalfunction of the on-load tap-changer and the motor-drive.

These tap-change operations are to be performed over theentire operating range.

Make sure that the position indicators of the motor-drive andthe on-load tap-changer (inspection glass on the tap-changerhead) have the same reading in every operating position.

Check that the automatic switch-off is working in both endpositions and check the function of the electrical and mecha-nical end position limits (see Operating Instructions no. 271for the motor-drive ED-Ex).

CAUTION

If the position indicators on the on-load tap-changer andthe motor-drive read different operating positions, there isa coupling fault.Operating the equipment with incorrect coupling willresult in damage to the on-load tap-changer and to thetransformer.The transformer may not be put into operation.

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14.2 Complete oil filling

In order to comply with the explosion protection require-ments, the complete oil system of the on-load tap-changerhas to be fully vented.

Bleed as follows:

• bleed the oil chamber of the tap-changer head usingthe bleeder valve in the tap-changer head cover (E1):Open the screw cap M30/w. s. 36, torque 10 Nm (fig. 17),lift the valve tappet using a screwdriver.

• the elbow connection with bleeder screw:screw cap M16/w.s. 22, max. torque 9 Nm, bleederscrew M6 with slotted head, torque 2 Nm (fig. 18).

14.3 Ground Connections

Connect the ground screw of the tap-changer head to thetransformer cover (1 screw M12 with nut (w. s. 19),torque 60 Nm, fig. 19).

Connect the ground screw of the motor-drive protectivehousing to the transformer tank.

14.4 Electrical tests on the transformer

The electrical tests required for the final inspection of thetransformer can be performed after the afore-mentionedwork has been completed.

14 Commissioning the OLTC at the transformer manufacturer's site

CAUTION

Vacuum filling is imperative after installation and main-tenance.

r

KHW 115717

r

KHW 115818

19

r

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16 Commissioning at the operating site

15 Transport to the operating site16 Commissioning at the operating site

If the motor-drive unit has to be dismounted for thetransport of the transformer to the operating site, operate itto the adjustment position and then uncouple it.

Follow the instructions in section 13.1 and 13.3 in order tore-install the motor-drive unit.

This pipe should be connected on the tap-changer headbetween the connections E2 and one of the free connectionsR, S or Q.

It is sufficient to lower the oil level in the tap-changer headby approx. 7 litres for short standing periods, 2-4 weeks,without an oil conservator.

If the transformer is completely emptied of oil, the tap-changer insulating oil must also be completely drained.

The interior of the oil compartment is to be conserved in thesame way as the transformer (e.g. by filling with nitrogen).

For longer standing periods, the motor-drive unit heatingmust be connected and operated.

15 Transport to the operating site

CAUTION

Do not operate the motor-drive unit while it is not coupledto the on-load tap-changer.

NOTE

If the transformer is filled with oil, but is stored ortransported without an oil conservator, a pipe must beconnected between the interior of the tap-changer oilcompartment and the transformer oil chamber to equalizethe static pressure.

Before commissioning the transformer, a function test mustbe carried out on the on-load tap-changer and motor-driveunit according to section 14.1. The function of the protectiverelay should also be checked at this point.

As a control test, trigger the connected circuit breaker byactivating the test button "OFF" of the protective relay.Make sure that closing of the circuit breakers is only possibleagain after the protective relay has been brought to the"IN SERVICE" position by pressing the other test button.

After energizing the transformer, tap change operationsunder load can be performed.

NOTE

The protective relay must be inserted into the trippingcircuit of the circuit breakers so the transformer is im-mediately shut down by the circuit breakers when theprotective relay is triggered (see Operating Instructionsno. 272 for the protective relay RS 2001-Ex).

CAUTION

Check that all stop valves between the oil conservator andthe on-load tap-changer are open.

CAUTION

The relevant safety regulations must be observed here.

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17 Monitoring during service18 Failures

Monitoring the on-load tap-changer and motor-drive unit islimited to regular visual inspections of the tap-changer head,protective relay and motor-drive unit. These can be carriedout at the same time as the usual control inspections on thetransformer.

Pay particular attention to the following:

• sealing points of the tap-changer head, protective relayand connected pipes are to be oil-proof,

• sealings of the protective housing of the motor-driveunit,

• trouble-free functioning of the built-in electrical heatingin the protective housing of the motor-drive unit,

• silicagel breather for the tap-changer oil conservator is tobe in perfect condition

• function test of the protective relay according to Opera-ting Instructions no. 272 for protective relay RS 2001-Ex.

The insulating oils in the transformer should be monitored bythe user according to the relevant regulations (also seesection 19).

17 Monitoring during service 18 Failures

For more serious problems with the on-load tap-changer ormotor-drive unit, which cannot be rectified easily on site, orif the protective relay is triggered, please inform yourauthorised MR representative or the transformermanufacturer. Alternatively, contact us directly at

Maschinenfabrik Reinhausen GmbHTechnical ServicePostfach 12 03 6093025 RegensburgGermanyTelephone: (+49) 9 41 40 90-0Fax: (+49) 9 41 40 90-501Email: [email protected]: www.reinhausen.com

WARNING

If the protective relay is triggered, the on-load tap-changer and transformer must be thoroughly checked. Thisinvolves withdrawing the tap-changer insert and checkingit according to the Maintenance Manual. For more detailsof the protective relay RS 2001-Ex, follow the OperatingInstructions no. 272.This applies analogously when other protective devicee. g. the pressure relief device trip in the on-load tap-changer.Only operate the equipment again when you are sure thereis no damage to the on-load tap-changer or to thetransformer.Operating the transformer without prior checking is notpermitted as serious damage to the on-load tap-changerand the transformer can occur.

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19 Maintenance

Maintenance intervals:Maintenance has to be carried out on the VACUTAP® VV-Ex after every 300,000 tap-change operations.

The scope and type of maintenance are specified in thecorresponding Maintenance Instructions from MR.

If the appropriate preparations are made, a proper main-tenance can be carried out within a day.

The on-load tap-changer VACUTAP® VV-Ex with VACUTAP®-vacuum switching technology has considerably longermaintenance intervals when compared to conventional tap-changers with oil switching technology, which dramaticallylowers operating and maintenance costs.This means that properly conducted maintenance is even moreimportant. For this reason we emphatically recommend thatour Technical Service Department carry out each maintenance.As well as guaranteeing that all work is properly carried out,specific components are also retro-fitted to the latest standardof technology.

If a maintenance is not carried out by our Technical Servicedepartment, please ensure that the personnel who carry outthe maintenance are trained by MR or are otherwise suitablyqualified to carry out the work.

19 Maintenance

CAUTION

The oil compartment and its associated oil conservatormust only be filled with new insulating oil for transformersaccording to IEC 60296 (Specification for unused mineralinsulating oils for transformers and switchgear) and IEC60422 (Supervision and maintenance guide for mineralinsulating oils in electrical equipment). For dielectricstrength limit values see table 1. The use of any other oilsmay put the trouble-free operation of the on-load tap-changer and the transformer at risk.

WARNING

Disregarding the maintenance intervals or an incomplete /improper maintenance can lead to severe damage on theon-load tap-changer and the transformer.

In such a case, we would ask you to forward us a report on themaintenance performed, to complete our maintenancerecords. For inquires about spare parts we ask you to informus about the serial number (see the name plate on the motor-drive unit) and the number of switching operations.

In addition to the maintenance intervals mentioned above theswitching elements of the diverter switch unit must be replacedafter 600,000 tap-change operations, the diverter switch insertand the gearing mechanism after 1,200,000 tap-changeoperations and the change-over selector of the on-load tap-changer after 2,100,000 tap-change operations (counter rea-ding/motor drive).

In addition, the limit values in Table I below should be con-sidered when exchanging or treating the diverter switch oil.

Limit values for the exchange or treatment of the tap-changer oil:

Table I

*) measured according to IEC 60156

The temperature of the oil sample at the time of measuring the dielectric strength should be noted.The given values for dielectric strength are valid for oil temperatures of 20 ± 5 °C.

On-load tap-changer Dielectric Strength*)

V V III 250 Y, V V III 400 Y, V V III 600 Y 30 kV/2.5 mm (minimum)

V V I 401 !, V V III 250 !, V V III 400 !" V V III 600 ! 40 kV/2.5 mm (minimum)

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20 Appendix

20 Appendix

On-load tap-changer VACUTAP® VV-Ex, tap-changer head .............................................................................................. 725210 Page 28

On-load tap-changer VACUTAP® VV, tap-changer head ................................................................................................... 898863 Page 29

On-load tap-changer VACUTAP® VV-Ex, installation drawing ......................................................................................... 898864 Page 30

On-load tap-changer VACUTAP® VV-Ex, drilling template for the tap-changer head ............................................... 893787 Page 31

On-load tap-changer VACUTAP® VV-Ex, assembly drawing .............................................................................................. 898866 Page 32

On-load tap-changer VACUTAP® VV-Ex, mounting of the bell-type cover ................................................................... 899110 Page 33

On-load tap-changer VACUTAP® VV-Ex, position of the on-load tap-changer ........................................................... 899409 Page 34

On-load tap-changer VACUTAP® VV-Ex, transport instructions ....................................................................................... 899063 Page 35

On-load tap-changer VACUTAP® VV-Ex, switching sequence .......................................................................................... 899083 Page 36

On-load tap-changer VACUTAP® VV-Ex, positioning of connection terminals ........................................................... 899051 Page 37

Protective Relay RS 2001-Ex ...................................................................................................................................................... 723653 Page 38

TAPMOTION® ED-S-Ex, protective housing ............................................................................................................................. 898743 Page 39

TAPMOTION® ED-Ex, protective housing-Ex, damped against vibration ........................................................................ 734850 Page 40

Bevel gear, dimension drawing ................................................................................................................................................. 892916 Page 41

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On-load tap-changer VACUTAP® VV-ExTap-changer head

72521001E

2

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On-load tap-changer VACUTAP® VV-ExTap-changer head

8988637E

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On-load tap-changer VACUTAP® VV-ExInstallation drawing

8988646E

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On-load tap-changer VACUTAP® VV-Ex

Drilling template for the tap-changer head8937870E

3 mm thick

Marks pounded

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On-load tap-changer VACUTAP® VV-ExAssembly drawing

8988667E

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Mounting of the bell-type cover8991103E

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On-load tap-changer VACUTAP® VV-ExPosition of the on-load tap-changer

8994092E

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Transport instructions8990632E

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On-load tap-changer VACUTAP® VV-ExSwitching sequence

8990831E

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Positioning of connection terminals8990515E

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Protective relay RS 2001-Ex

Dimension drawing7236530E

Inspectionwindow

Name plate

GasketGasket

Cable gland M25 x 1.5

Test push buttonsIN SERVICE OFF

(reset) (test tripping)

The arrow must always point towards the oilpipe leading to the oil conservator of the

transformer.

Plan view of test push buttons(cover removed)

1)NO - normally open, NC - normally closed

The protective relay is to be connected in such a way that if it is energized, the power transformer is switched off immediately by thecorresponding circuit breakers.

0.65 - 2NO / EX1 1.2 - 2NO / EX 2 A

3.0 - 2NO / EX4.8 - 2NO / EX

0.65 - 2NC / EX2 1.2 - 2NC / EX 2 B

3.0 - 2NC / EX4.8 - 2NC / EX

0.65 - NO + NC / EX3 1.2 - NO + NC / EX 1 A und 1 B

3.0 - NO + NC / EX4.8 - NO + NC / EX

Key of versions

Version Arrangement of terminalsRelay designation1) Reedswitch

Contact positions

IN SERVICE OFF

Earth terminal

Identificationlabel

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TAPMOTION® ED-S-ExProtective housing

8987434E

40 273/02/01/0



TAPMOTION® ED-Ex

Protective housing-Ex, damped against vibration7348500E

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Bevel gearDimension drawing

8929166E

e 1 =

205

for

sta

ndar

d de

sign

e 2 =

215

for

desi

gn w

ith b

all j

oint

©Maschinenfabrik Reinhausen GmbH Telefon +49 941 40 90-0Falkensteinstraße 8 Telefax +49 941 40 90-11193059 Regensburg E-Mail [email protected]

BA 273/02 en • 0208/20 • 273/02/01/0 • F0144601 • Printed in Germany

www.reinhausen.com ©Maschinenfabrik Reinhausen GmbH Phone +49 941 40 90-0Falkensteinstrasse 8 Fax +49 941 40 90-11193059 Regensburg, Germany E-mail [email protected]