MR OILTAP R Installation and operation manual

On-Load Tap-Changer
OILTAP® R
Installation and Commissioning Instructions
4427410/00 EN

© All rights reserved by Maschinenfabrik Reinhausen
Dissemination and reproduction of this document and use and disclosure of its content are strictly prohibited
unless expressly permitted.
Infringements will result in liability for compensation. All rights reserved in the event of the granting of patents,
utility models or designs.
The product may have been altered since this document was published.
We reserve the right to change the technical data, design and scope of supply.
Generally the information provided and agreements made when processing the individual quotations and orders
are binding.
The original operating instructions were written in German.

Table of contents
Maschinenfabrik Reinhausen GmbH 2015 34427410/00 EN OILTAP® R
Table of contents
1Introduction......................................................................................................................... 7
1.1 Validity................................................................................................................................................. 7
1.2 Manufacturer....................................................................................................................................... 7
1.3 Subject to change without notice......................................................................................................... 7
1.4 Completeness...................................................................................................................................... 7
1.5 Safekeeping......................................................................................................................................... 8
1.6 Notation conventions........................................................................................................................... 8
1.6.1 Symbols................................................................................................................................................................. 8
1.6.2 Hazard communication system............................................................................................................................. 9
1.6.3 Information system.............................................................................................................................................. 11
2Safety................................................................................................................................. 12
2.1 General safety information................................................................................................................ 12
2.2 Appropriate use................................................................................................................................. 12
2.3 Inappropriate use............................................................................................................................... 13
2.4 Personnel qualification...................................................................................................................... 13
2.5 Operator's duty of care...................................................................................................................... 13
2.6 Personal protective equipment.......................................................................................................... 14
2.7 Protective devices............................................................................................................................. 15
2.7.1 Protective relay RS.............................................................................................................................................. 15
2.7.2 Pressure monitoring device................................................................................................................................. 15
2.7.3 Rupture disk ....................................................................................................................................................... 16
2.7.4 Pressure relief device MPreC®........................................................................................................................... 16
2.7.5 Tap-change supervisory control.......................................................................................................................... 16
2.7.6 Temperature monitoring...................................................................................................................................... 16
3Product description.......................................................................................................... 17
3.1 Scope of delivery............................................................................................................................... 17
3.2 On-load tap-changer.......................................................................................................................... 17
3.2.1 Function description............................................................................................................................................ 17
3.2.2 Setup/versions..................................................................................................................................................... 18
3.2.3 Name plate.......................................................................................................................................................... 20
3.3 Drive shaft......................................................................................................................................... 21
3.3.1 Function description............................................................................................................................................ 21
3.3.2 Setup/models of drive shaft................................................................................................................................. 21

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3.4 RS protective relay............................................................................................................................ 24
3.4.1 Function description............................................................................................................................................ 24
3.4.2 Setup/models of protective relay......................................................................................................................... 24
3.5 Pressure monitoring device DW........................................................................................................ 26
3.5.1 Function description............................................................................................................................................ 26
3.5.2 Structure/versions of the pressure-operated relay.............................................................................................. 27
3.6 OF 100 Oil Filter Unit......................................................................................................................... 29
4Packaging, transport and storage................................................................................... 30
4.1 Packaging.......................................................................................................................................... 30
4.1.1 Suitability............................................................................................................................................................. 30
4.1.2 Markings.............................................................................................................................................................. 30
4.2 Transportation, receipt and handling of shipments............................................................................ 31
4.3 Storage of shipments......................................................................................................................... 32
4.4 Unpacking shipments and checking for transportation damages...................................................... 33
5Mounting............................................................................................................................ 34
5.1 Preparatory work............................................................................................................................... 34
5.1.1 Fitting mounting flange on transformer cover...................................................................................................... 35
5.1.2 Fitting stud bolts on mounting flange................................................................................................................... 35
5.2 Installing the standard version on-load tap-changer in the transformer............................................ 36
5.2.1 Fastening on-load tap-changer to transformer cover.......................................................................................... 36
5.2.2 Connecting tap winding and on-load tap-changer take-off lead.......................................................................... 44
5.2.3 Carrying out the transformer ratio test................................................................................................................. 48
5.2.4 Measuring DC resistance on transformer............................................................................................................ 51
5.2.5 Drying on-load tap-changer in autoclave............................................................................................................. 51
5.2.6 Drying on-load tap-changer in transformer tank.................................................................................................. 54
5.3 Installing the on-load tap-changer in the transformer (bell-type tank version)................................... 67
5.3.1 Inserting on-load tap-changer into supporting structure...................................................................................... 67
5.3.2 Connecting tap winding and on-load tap-changer take-off lead.......................................................................... 75
5.3.3 Carrying out the transformer ratio test................................................................................................................. 78
5.3.4 Measuring DC resistance on transformer............................................................................................................ 81
5.3.5 Drying on-load tap-changer in autoclave............................................................................................................. 81
5.3.6 Removing on-load tap-changer head.................................................................................................................. 84
5.3.7 Attaching bell-type tank and connecting on-load tap-changer head with on-load tap-changer........................... 90
5.3.8 Drying on-load tap-changer in transformer tank................................................................................................ 101
5.4 Filling the oil compartment of the on-load tap-changer with oil....................................................... 115

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5.5 Fitting protective devices and drive components............................................................................. 116
5.5.1 Connecting the tap-change supervisory control (if installed)............................................................................. 116
5.5.2 Installing protective relay in piping and connecting........................................................................................... 117
5.5.3 Installing and connecting the pressure-operated relay...................................................................................... 128
5.5.4 Fitting motor-drive unit....................................................................................................................................... 131
5.5.5 Fitting bevel gear............................................................................................................................................... 131
5.5.6 Fitting drive shaft............................................................................................................................................... 132
5.5.7 Centering on-load tap-changer and motor-drive unit......................................................................................... 162
5.5.8 Installing electrics for motor-drive unit............................................................................................................... 162
6Commissioning the on-load tap-changer at the transformer manufacturer's site... 163
6.1 Bleeding on-load tap-changer head and suction pipe..................................................................... 163
6.1.1 Bleeding on-load tap-changer head.................................................................................................................. 163
6.1.2 Bleeding suction pipe on pipe connection S...................................................................................................... 164
6.2 Grounding the on-load tap-changer................................................................................................. 164
6.3 Performing tests on motor-drive unit............................................................................................... 165
6.4 Performing trial tap-change operations........................................................................................... 165
6.5 High-voltage tests on the transformer............................................................................................. 166
7Transporting transformer to the operating site........................................................... 168
7.1 Transport with removed drive.......................................................................................................... 168
7.2 Transport with oil fill and without oil conservator............................................................................. 168
7.3 Transport without oil fill.................................................................................................................... 169
7.3.1 Emptying oil compartment via pipe connection S.............................................................................................. 169
8Commissioning the transformer at the operating site................................................ 171
8.1 Checking motor-drive unit................................................................................................................ 171
8.2 Checking protective relay................................................................................................................ 172
8.2.1 Checking protective relay (RS 2001, 2001/V, 2001/H, 2001/E, 2001/5, 2001/R, 2003).................................... 172
8.2.2 Checking protective relay (RS 2004)................................................................................................................. 172
8.3 Checking pressure monitoring device............................................................................................. 172
8.4 Filling the oil compartment of the on-load tap-changer with oil....................................................... 173
8.5 Bleeding on-load tap-changer head and suction pipe..................................................................... 176
8.5.1 Bleeding on-load tap-changer head.................................................................................................................. 176
8.5.2 Bleeding suction pipe on pipe connection S...................................................................................................... 178
8.6 Performing trial tap-change operations........................................................................................... 178
8.7 Commissioning the transformer....................................................................................................... 179

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9Fault elimination.............................................................................................................. 180
9.1 Tripping of the protective relay and re-commissioning the transformer........................................... 182
9.1.1 Flap valve in IN SERVICE position................................................................................................................... 183
9.1.2 Flap valve in OFF position................................................................................................................................. 183
9.1.3 Re-commissioning the transformer................................................................................................................... 183
9.2 Tripping the pressure-operated relay and putting the transformer back into operation................... 184
9.2.1 Sensor in the OPERATION position.................................................................................................................. 184
9.2.2 Sensor in the OFF position................................................................................................................................ 184
9.2.3 Re-commissioning the transformer................................................................................................................... 185
10 Technical data................................................................................................................. 186
10.1 Technical data for protective relay................................................................................................... 186
10.2 Special models of protective relay................................................................................................... 187
10.2.1 Protective relay with CO change-over contact as tripping switch ..................................................................... 187
10.2.2 Protective relay with several dry-reed magnetic switches................................................................................. 187
10.3 Technical data for pressure monitoring device................................................................................ 188
11 Appendix.......................................................................................................................... 189
11.1 Limit values for dielectric strength and water content of on-load tap-changer oil............................ 189
11.2 OILTAP® R, installation drawing for selector size C/D (896705).................................................... 190
11.3 OILTAP® R, installation drawing for selector size E (897873)........................................................ 191
11.4 OILTAP® R, R I 2002/2003-C/D, R I 3003-C/D, bridges for parallel connection of selector plane
(896706).......................................................................................................................................... 192
11.5 OILTAP® R, R I 2002/2003-E, R I 3003-E, bridges for parallel connection of selector plane (898713)
......................................................................................................................................................... 193
11.6 OILTAP® R, on-load tap-changer head (893899)........................................................................... 194
11.7 OILTAP® R, flange for pressure relief device (895168).................................................................. 195
11.8 Tracing template for on-load tap-changer head (890183)............................................................... 196
11.9 OILTAP® R, supporting flange for bell-type tank installation up to Um=300 kV (896762).............. 197
11.10 OILTAP® R, supporting flange for bell-type tank installation up to Um=362 kV (725912).............. 198
11.11 OILTAP® R, tap selector connection contacts and change-over selector connection contacts for
selector size E (897868).................................................................................................................. 199
11.12 Lifting traverse for bell-type tank installation (890180).................................................................... 200
11.13 Socket wrench for kerosene drain plug (890182)............................................................................ 201
11.14 Bevel gear CD 6400, dimensional drawing (892916)...................................................................... 202
Glossary........................................................................................................................... 203

1 Introduction
Maschinenfabrik Reinhausen GmbH 2015 74427410/00 EN OILTAP® R
Introduction
This technical file contains detailed descriptions of the safe and proper in-
stallation, connection, and commissioning of the product.
It also includes safety instructions and general information about the prod-
uct.
Information about operation can be found in the operating instructions.
This technical file is intended solely for specially trained and authorized per-
sonnel.
Validity
The document supplied with the product is always the valid version. This
technical file is configured for the specific order and applies to the following
products, the serial numbers of which can be found on the delivery docu-
ments:
▪ OILTAP® R type on-load tap-changer
▪ RS protective relay
▪ Pressure monitoring device DW 2000 (optional)
▪ Drive shaft
Manufacturer
The product is manufactured by:
Maschinenfabrik Reinhausen GmbH
Falkensteinstraße 8
93059 Regensburg, Germany
Tel.: [phone]
Fax: [phone]
E-mail: [email protected]
Further information on the product and copies of this technical file are avail-
able from this address if required.
Subject to change without notice
The information contained in this technical file comprises the technical speci-
fications approved at the time of printing. Significant modifications will be in-
cluded in a new edition of the technical file.
The document number and version number of this technical file are shown in
the footer.
Completeness
This technical file is incomplete without the supporting documentation.
1
1.1
1.2
1.3
1.4

1 Introduction
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The following documents apply:
▪ Unpacking instructions (included in the scope of delivery)
▪ Supplement (included in the scope of delivery)
▪ Routine test report (included in the scope of delivery)
▪ Connection diagrams (included in the scope of delivery)
▪ Dimensional drawings (included in the scope of delivery)
▪ Technical data - General section (available on request)
▪ Technical data - Product-specific section (available on request)
Also observe generally valid legislation, standards, and guidelines as well as
specifications on accident prevention and environmental protection in the re-
spective country of use.
Safekeeping
This technical file and all supporting documents must be kept ready at hand
and accessible for future use at all times.
Notation conventions
This section contains an overview of the symbols and textual emphasis
used.
Symbols
Symbol Meaning
Wrench size
Tightening torque
Number and type of fastening materials used
Fill with oil
Cut open, cut through
Clean
Visual inspection
1.5
1.6
1.6.1

1 Introduction
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Symbol Meaning
Use your hand
Adapter ring
Apply a coat of paint
Use a file
Grease
Coupling bolt
Use a ruler
Use a saw
Hose clip
Wire eyelet, safety wire
Use a screwdriver
Table 1: Symbols
Hazard communication system
Warnings in this technical file are displayed as follows.
Warning relating to section
Warnings relating to sections refer to entire chapters or sections, sub-sec-
tions or several paragraphs within this technical file. Warnings relating to
sections use the following format:
1.6.2
1.6.2.1

1 Introduction
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WARNING Type and source of danger
Consequences
► Action
► Action
Embedded warning information
Embedded warnings refer to a particular part within a section. These warn-
ings apply to smaller units of information than the warnings relating to sec-
tions. Embedded warnings use the following format:
DANGER! Instruction for avoiding a dangerous situation.
Signal words and pictograms
The following signal words are used:
Signal
word
Meaning
DANGER Indicates a hazardous situation which, if not avoided, will
result in death or serious injury.
WARNING Indicates a hazardous situation which, if not avoided, could
result in death or serious injury.
CAUTION Indicates a hazardous situation which, if not avoided, could
result in injury.
NOTICE Indicates measures to be taken to prevent damage to
property.
Table 2: Signal words in warning notices
Pictograms warn of dangers:
Pictogram Meaning
Warning of a danger point
Warning of dangerous electrical voltage
Warning of combustible substances
1.6.2.2
1.6.2.3

1 Introduction
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Pictogram Meaning
Warning of danger of tipping
Table 3: Pictograms used in warning notices
Information system
Information is designed to simplify and improve understanding of particular
procedures. In this technical file it is laid out as follows:
Important information.
1.6.3

2 Safety
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Safety
General safety information
This technical file contains detailed descriptions of the safe and proper in-
stallation, connection, and commissioning of the product.
▪ Read this technical file through carefully to familiarize yourself with the
product.
▪ Particular attention should be paid to the information given in this chap-
ter.
Appropriate use
If used as intended and in compliance with the requirements and conditions
specified in this technical file as well as the warning notices in this technical
file and attached to the product, then the product does not present any haz-
ards to people, property or the environment. This applies throughout the
product's entire life, from delivery through installation and operation to disas-
sembly and disposal.
The operational quality assurance system ensures a consistently high quality
standard, particularly in regard to the observance of health and safety re-
quirements.
The following is considered appropriate use
▪ Only operate the product in accordance with this technical file and the
agreed delivery conditions and technical data
▪ Use the equipment and special tools supplied solely for the intended
purpose and in accordance with the specifications of this technical file
▪ Use the product only with the transformer specified in the order
▪ You will find the standard valid for the product and the year of issue on
the name plate
▪ The serial numbers of on-load tap-changers and on-load tap-changer
accessories (drive, drive shaft, bevel gear, protective relay etc.) must
match if the on-load tap-changers and on-load tap-changer accessories
are supplied as a set for one order.
DANGER Danger of death or severe injury and damage to property and
the environment!
Danger of death or severe injury and damage to property and the environ-
ment due to electrical voltage, falling and/or tipping parts as well as danger-
ous cramped conditions resulting from moving parts!
► Adherence to the following prerequisites and conditions is mandatory.
► Adhere to warning notices.
Since the on-load tap-changer was dimensioned as per IEC 60214-1, it can
switch currents of up to twice the value of the rated through current.
2
2.1
2.2

2 Safety
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On-load tap-change operations are not to be performed during operating
conditions with higher currents.
Examples of such operating conditions are:
▪ Inrush current impulses when transformers are switched on
▪ Short circuit
The rated step voltage may be briefly exceeded by up to 10 % as long as the
rated through current is not exceeded. Such an operating condition can oc-
cur due to overexcitation of the transformer after load shedding, for example.
The on-load tap-changer can be operated in the temperature range of the
surrounding transformer oil of between -25 ° and +105 °C and with overload
up to +115 °C in accordance with IEC 60214-1.
Inappropriate use
Use is considered to be inappropriate if the product is used other than as de-
scribed in the Appropriate use section. Please also note the following:
▪ Risk of explosion and fire from highly flammable or explosive gases, va-
pors, or dusts. Do not operate product in areas at risk of explosion.
▪ Unauthorized or inappropriate changes to the product may lead to per-
sonal injury, material damage, and operational faults. Only modify prod-
uct following discussion with Maschinenfabrik Reinhausen GmbH.
Personnel qualification
The product is designed solely for use in electrical energy systems and facili-
ties operated by appropriately trained staff. This staff comprises people who
are familiar with the installation, assembly, commissioning and operation of
such products.
Operator's duty of care
To prevent accidents, disruptions and damage as well as unacceptable ad-
verse effects on the environment, those responsible for transport, installa-
tion, operation, maintenance and disposal of the product or parts of the prod-
uct must ensure the following:
▪ All warning and hazard notices are complied with.
▪ Personnel are instructed regularly in all relevant aspects of operational
safety, the operating instructions and particularly the safety instructions
contained therein.
▪ Regulations and operating instructions for safe working as well as the
relevant instructions for staff procedures in the case of accidents and
fires are kept on hand at all times and are displayed in the workplace
where applicable.
2.3
2.4
2.5

2 Safety
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▪ The product is only used when in a sound operational condition and
safety equipment in particular is checked regularly for operational relia-
bility.
▪ Only replacement parts, lubricants and auxiliary materials which are au-
thorized by the manufacturer are used.
▪ The specified operating conditions and requirements of the installation
location are complied with.
▪ All necessary devices and personal protective equipment for the specific
activity are made available.
▪ The prescribed maintenance intervals and the relevant regulations are
complied with.
▪ Installation, electrical connection and commissioning of the product may
only be carried out by qualified and trained personnel in accordance
with this technical file.
▪ The operator must ensure appropriate use of the product.
Personal protective equipment
Personal protective equipment must be worn during work to minimize risks to
health.
▪ Always wear the personal protective equipment required for the job at
hand.
▪ Follow information about personal protective equipment provided in the
work area.
Always wear
Protective clothing
Close-fitting work clothing with a low
breaking strength, with tight sleeves and
with no protruding parts. It mainly serves
to protect the wearer against being caught
by moving machine parts.
Do not wear any rings, necklaces or other
jewelry.
Safety shoes
To protect against falling heavy objects
and slipping on slippery surfaces.
Table 4: Personal protective equipment to be worn at all times
2.6

2 Safety
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Wear the following in spe-
cial environments
Special personal protective equipment
is needed in special environments.
The choice of equipment depends on
the circumstances.
Safety glasses
To protect the eyes from flying parts and
splashing liquids.
Hard hat
To protect from falling and flying parts and
materials.
Hearing protection
To protect from hearing damage.
Table 5: Personal protective equipment to be worn in special environments
Protective devices
The following protective devices for the product are included as standard in
the scope of delivery or are available as options.
Protective relay RS
The protective relay RS is an oil flow-controlled relay in accordance with IEC
60214-1. It is installed between the on-load tap-changer head and the oil
conservator of the on-load tap-changer.
It triggers when the specified oil flow between oil compartment of the on-load
tap-changer and oil conservator is exceeded.
Pressure monitoring device
The pressure monitoring device DW 2000 is installed on the outside of the
on-load tap-changer and is tripped by unacceptable static and dynamic pres-
sures in the on-load tap-changer oil vessel.
Additional use of a pressure-operated relay also requires installation of the
provided RS 2001 protective relay.
The features and characteristics of the pressure monitoring device comply
with the respective applicable version of IEC publication 60214-1.
2.7
2.7.1
2.7.2

2 Safety
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Rupture disk
The rupture disk is a pressure relief device without signaling contact in ac-
cordance with IEC 60214-1 and is located in the on-load tap-changer head
cover.
The rupture disk responds to a defined overpressure in the oil compartment
of the on-load tap-changer.
Pressure relief device MPreC®
On request, in place of the rupture disk MR will supply a pre-fitted pressure
relief device MPreC® that responds to a defined overpressure in the oil com-
partment of the on-load tap-changer.
The on-load tap-changer therefore meets the requirements of IEC 60214-1
regarding pressure relief devices.
Tap-change supervisory control
The tap-change supervisory control monitors both the drive shaft between
on-load tap-changer(s) and motor-drive unit and the correct switching of the
diverter switch.
Temperature monitoring
The temperature monitoring device monitors the oil temperature in the oil
compartment of the on-load tap-changer.
2.7.3
2.7.4
2.7.5
2.7.6

3 Product description
Maschinenfabrik Reinhausen GmbH 2015 174427410/00 EN OILTAP® R
Product description
This chapter contains an overview of the design and function of the product.
Scope of delivery
The product is packaged with protection against moisture and is usually de-
livered as follows:
▪ Oil compartment with on-load tap-changer head and built-in diverter
switch insert
▪ Selector
▪ Motor-drive unit
▪ Drive shaft with coupling parts and bevel gear
▪ Protective device
▪ Technical files
Please refer to the delivery slip for full details of scope of delivery.
Single-phase on-load tap-changers are also available as an on-load tap-
changer set with a common motor-drive unit.
Note the following information:
▪ Check the shipment for completeness on the basis of the shipping docu-
ments.
▪ Store the parts in a dry place until installation.
▪ The product must remain in its airtight, protective wrapping and may on-
ly be removed immediately before installation
You will find more information in the "Packaging, transport, and storage"
[► 30] chapter.
On-load tap-changer
Function description
On-load tap-changers are used to adjust the transmission ratio of transform-
ers without interrupting the load flow. Fluctuations in voltage occurring in the
power transmission grid, for example, can therefore be compensated for. For
this purpose, on-load tap-changers are fitted in transformers and connected
to the active part of the transformer.
A motor-drive unit, which receives a control impulse (e.g. from a voltage reg-
ulator), changes the on-load tap-changer's operating position, as a result of
which the transmission ratio of the transformer is adapted to the operating
requirements.
3
3.1
3.2
3.2.1

3 Product description
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Figure 1: System overview of on-load tap-changer transformer
1 Transformer tank 6 Gear unit
2 Motor-drive unit 7 On-load tap-changer
3 Vertical drive shaft 8 Protective relay
4 Bevel gear 9 Oil conservator
5 Horizontal drive shaft 10 Active part
Setup/versions
The on-load tap-changer consists of the on-load tap-changer head, oil com-
partment with built-in diverter switch insert, and the tap selector mounted be-
low (also available with change-over selector on request).
The design and designation of the most important on-load tap-changer com-
ponents are shown in the installation drawings in the appendix.
For the number of maximum operating positions of the on-load tap-changer,
refer to the technical data.
3.2.2

3 Product description
Maschinenfabrik Reinhausen GmbH 2015 194427410/00 EN OILTAP® R
Figure 2: OILTAP® R on-load tap-changer
1 On-load tap-changer head 3 Tap selector
2 Oil compartment 4 Change-over selector
Pipe connections
The on-load tap-changer head features 4 pipe connections for different pur-
poses.
Depending on the order, some or all of these pipe connections are fitted with
pipe bends ex factory. All pipe bends without terminal box for the tap-change
supervisory control can be freely swiveled once the pressure ring is loos-
ened.
3.2.2.1

3 Product description
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Figure 3: Pipe connections with pipe bends
Pipe connection Q
Pipe connection Q is closed with a blank cover and, depending on the on-
load tap-changer type, is intended for the bushing of the tap-change supervi-
sory control supplied as an option or for connecting the oil filter unit.
The functions of the R and Q pipe connections can be interchanged.
Pipe connection S
The pipe bend on pipe connection S features a vent screw and can be con-
nected to a pipe that ends with a drain valve on the side of the transformer
tank at operating height. If the on-load tap-changer is fitted with an oil suc-
tion pipe, the on-load tap-changer can be completely emptied via pipe con-
nection S.
Pipe connection R
Pipe connection R is provided for the attachment of the protective relay and
the connection of the on-load tap-changer oil conservator and can be inter-
changed with pipe connection Q.
Pipe connection E2
The pipe connection E2 is closed with a blank cover. It leads into the oil tank
of the transformer, directly under the on-load tap-changer head and can be
connected to a collective pipe for the Buchholz relay, if necessary. This pipe
connection serves a further purpose, namely to equalize the pressure be-
tween the transformer tank and oil compartment of the on-load tap-changer,
which is necessary for drying and transportation of the transformer.
Name plate
The name plate is on the on-load tap-changer head cover.
3.2.3