VACUTAP® RMV-II On-Load Tap-Changer Operating Instructions PDF

ON-LOAD TAP-CHANGER VACUTAP® RMV-II OPERATING INSTRUCTIONS 2159612/03 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 liabil...

ON-LOAD TAP-CHANGER VACUTAP® RMV-II OPERATING INSTRUCTIONS 2159612/03 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 Table of contents 1 Introduction......................................................................................................................... 6 1.1 Validity................................................................................................................................................ 6 1.2 Manufacturer....................................................................................................................................... 6 1.3 Completeness..................................................................................................................................... 6 1.4 Safekeeping........................................................................................................................................ 6 1.5 Notation conventions.......................................................................................................................... 7 1.5.1 Hazard communication system............................................................................................................................. 7 1.5.2 Information system................................................................................................................................................ 8 1.5.3 Instruction system................................................................................................................................................. 8 2 Safety................................................................................................................................. 10 2.1 Appropriate use................................................................................................................................ 10 2.2 Fundamental safety instructions....................................................................................................... 11 2.3 Personnel qualification...................................................................................................................... 13 2.4 Personal protective equipment......................................................................................................... 14 3 Product description.......................................................................................................... 16 3.1 Scope of delivery.............................................................................................................................. 16 3.2 On-load tap-changer......................................................................................................................... 16 3.2.1 Function description for on-load tap-changer...................................................................................................... 16 3.2.2 On-load tap-changer design................................................................................................................................ 19 3.2.3 Protective devices............................................................................................................................................... 22 3.3 Motor-drive unit................................................................................................................................. 23 3.3.1 Function description............................................................................................................................................ 23 3.3.2 Motor-drive unit design........................................................................................................................................ 23 3.3.3 Protective devices in the motor-drive unit........................................................................................................... 24 3.4 Monitoring system (VIM)................................................................................................................... 25 3.4.1 Function description of monitoring system.......................................................................................................... 25 3.4.2 Monitoring system displays and controls............................................................................................................ 26 3.5 Dehydrating breather....................................................................................................................... 26 4 Packaging, transport and storage.................................................................................. 28 4.1 Packaging......................................................................................................................................... 28 4.1.1 Suitability............................................................................................................................................................. 28 4.1.2 Markings.............................................................................................................................................................. 28 Maschinenfabrik Reinhausen GmbH 2019 2159612/03 EN VACUTAP® RMV-II 3  Table of contents 4.2 Transportation, receipt and handling of shipments........................................................................... 29 4.3 Unpacking shipments and checking for transportation damages..................................................... 30 4.4 Things to note when putting back into storage................................................................................. 30 5 Fitting on-load tap-changer on transformer.................................................................. 31 5.1 Preparatory work.............................................................................................................................. 31 5.2 Fitting the on-load tap-changer......................................................................................................... 31 5.3 Connecting the tap winding and on-load tap-changer take-off lead................................................. 32 6 Fitting motor-drive unit.................................................................................................... 33 6.1 Preparatory work.............................................................................................................................. 33 6.2 Fitting motor-drive unit to on-load tap-changer................................................................................. 36 7 Checks after assembly..................................................................................................... 37 7.1 Manual check.................................................................................................................................... 37 7.2 Checking motor-drive unit and monitoring system............................................................................ 38 7.3 Transformer ratio test and DC resistance measurement.................................................................. 38 7.3.1 Carrying out the transformer ratio test................................................................................................................ 39 7.3.2 Measuring DC resistance on transformer........................................................................................................... 39 8 Drying the on-load tap-changer...................................................................................... 40 9 Filling on-load tap-changer with oil................................................................................ 41 10 Fitting accessories........................................................................................................... 42 10.1 Fitting dehydrating breather............................................................................................................. 42 10.2 Pressure relief device MPreC®........................................................................................................ 44 11 Commissioning at the transformer manufacturer's site............................................... 45 11.1 Checks before commissioning.......................................................................................................... 45 11.2 Performing trial tap-change operations............................................................................................. 46 11.3 High-voltage tests on the transformer............................................................................................... 46 12 Transporting transformer to installation site................................................................. 48 12.1 Transport with removed drive........................................................................................................... 48 13 Commissioning the transformer at the operating site.................................................. 49 13.1 Safety current circuits....................................................................................................................... 50 13.2 Performing trial tap-change operations............................................................................................. 50 13.3 Switching on transformer.................................................................................................................. 51 4 VACUTAP® RMV-II 2159612/03 EN Maschinenfabrik Reinhausen GmbH 2019 Table of contents 14 Actuating motor-drive unit with hand crank.................................................................. 52 15 Monitoring during operation........................................................................................... 53 15.1 Annual checks.................................................................................................................................. 53 15.1.1 Checking oil quality............................................................................................................................................. 53 15.1.2 Checking motor-drive unit................................................................................................................................... 54 15.1.3 Checking return to starting position..................................................................................................................... 54 15.2 Occasional visual checks.................................................................................................................. 54 16 Fault elimination............................................................................................................... 55 16.1 General information.......................................................................................................................... 55 16.2 Fault elimination overview................................................................................................................ 56 16.3 Monitoring system displays and controls.......................................................................................... 57 16.4 Overview of monitoring system operating statuses.......................................................................... 58 17 Maintenance...................................................................................................................... 59 17.1 Maintenance intervals....................................................................................................................... 59 17.2 Taking on-load tap-changer out of service....................................................................................... 60 17.3 Draining oil and testing oil quality..................................................................................................... 60 17.4 Investigating vacuum interrupters..................................................................................................... 60 17.4.1 External integrity check....................................................................................................................................... 60 17.4.2 Checking contact erosion indicator..................................................................................................................... 61 17.4.3 Replacing vacuum interrupter............................................................................................................................. 62 17.5 Checking by-pass switch.................................................................................................................. 62 17.6 Maintaining motor-drive unit............................................................................................................. 63 17.7 Maintaining monitoring system......................................................................................................... 63 17.8 Maintaining dehydrating breather..................................................................................................... 64 17.9 Preparing the on-load tap-changer for service................................................................................. 65 18 Technical data................................................................................................................... 66 18.1 General data..................................................................................................................................... 69 18.2 Temperature range........................................................................................................................... 69 19 Appendix........................................................................................................................... 70 19.1 Limit values for dielectric strength and water content of on-load tap-changer oil............................. 70 Maschinenfabrik Reinhausen GmbH 2019 2159612/03 EN VACUTAP® RMV-II 5  1 Introduction 1 Introduction This technical file contains detailed descriptions on the safe and proper in- stallation, connection, commissioning and monitoring of the product. In addition, this file contains technical data for selecting the appropriate product for a respective application. It also includes safety instructions and general information about the prod- uct. This technical document is intended solely for specially trained and autho- rized personnel. 1.1 Validity This technical file applies to the VACUTAP® RMV-II on-load tap-changer with the standard position designations 16L...N...16R. Drawings and illustrations in this technical file are provided for reference only. For specific details please refer to drawings submitted with each indi- vidual customer order. 1.2 Manufacturer This product is manufactured by: Reinhausen Manufacturing Inc. 2549 North 9th Avenue, 38343 Humboldt, Tennessee, USA Phone: +1 731 784 7681 Fax: +1 731 784 7682 E-mail: [email protected] Further information on the product and copies of this technical file are avail- able from this address if required. 1.3 Completeness This technical file is incomplete without the supporting documents: ▪ Technical data and drawings which are provided upon order confirmation and with the delivery. 1.4 Safekeeping Keep this technical file and all supporting documents ready at hand and ac- cessible for future use at all times. 6 VACUTAP® RMV-II 2159612/03 EN Maschinenfabrik Reinhausen GmbH 2019 1 Introduction 1.5 Notation conventions This section contains an overview of the symbols and textual emphasis used. 1.5.1 Hazard communication system Warnings in this technical file are displayed as follows. 1.5.1.1 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: WARNING Type of danger! Source of the danger and outcome. ► Action ► Action 1.5.1.2 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. 1.5.1.3 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 1: Signal words in warning notices Maschinenfabrik Reinhausen GmbH 2019 2159612/03 EN VACUTAP® RMV-II 7  1 Introduction Pictograms warn of dangers: Pictogram Meaning Warning of a danger point Warning of dangerous electrical voltage Warning of combustible substances Warning of danger of tipping Table 2: Pictograms used in warning notices 1.5.2 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. 1.5.3 Instruction system This technical file contains single-step and multi-step instructions. Single-step instructions Instructions which consist of only a single process step are structured as fol- lows: Aim of action ü Requirements (optional). ► Step 1 of 1. ð Result of step (optional). ð Result of action (optional). 8 VACUTAP® RMV-II 2159612/03 EN Maschinenfabrik Reinhausen GmbH 2019 1 Introduction Multi-step instructions Instructions which consist of several process steps are structured as follows: Aim of action ü Requirements (optional). 1. Step 1. ð Result of step (optional). 2. Step 2. ð Result of step (optional). ð Result of action (optional). Maschinenfabrik Reinhausen GmbH 2019 2159612/03 EN VACUTAP® RMV-II 9  2 Safety 2 Safety This technical file contains detailed descriptions on the safe and proper in- stallation, connection, commissioning and monitoring of the product. ▪ Read this technical file through carefully to familiarize yourself with the product. ▪ This technical file is a part of the product. ▪ Read and observe the safety instructions provided in this chapter in partic- ular. ▪ Observe the warnings in this technical file in order to avoid function-re- lated dangers. ▪ The product is manufactured on the basis of state-of-the-art technology. Nevertheless, risks to life and limb of the user or impairment of the prod- uct and other material assets may occur during use due to function-re- lated dangers. 2.1 Appropriate use The product is an on-load tap-changer and adjusts the transmission ratio of transformers without interrupting the load flow. The product is designed solely for use in electrical energy systems and facilities. 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 danger to people, property or the environment. This applies throughout service life of the prod- uct, from delivery to installation and operation through to disassembly and disposal. The following is considered appropriate use: ▪ Use the product only with the transformer specified in the order. ▪ The serial numbers of on-load tap-changer and on-load tap-changer ac- cessories (drive, drive shaft, bevel gear, protective relay, etc.) must match if the on-load tap-changer and on-load tap-changer accessories are sup- plied as a set for one order. ▪ You will find the standard valid for the product and the year of issue on the nameplate. ▪ Operate the product in accordance with this provided technical file, the agreed delivery conditions and technical data. ▪ Ensure that all necessary work is performed by qualified personnel only. ▪ Only use the equipment and special tools included in delivery for the in- tended purpose and in accordance with the specifications of this technical file. ▪ The on-load tap-changer is not intended to be used with an oil filter unit. Permitted electrical operating conditions In addition to the design data in accordance with the order confirmation, ob- serve the following limits for the through-current and the step voltage: 10 VACUTAP® RMV-II 2159612/03 EN Maschinenfabrik Reinhausen GmbH 2019 2 Safety In the standard version, the on-load tap-changer is designed for sinusoidal 50/60 Hz AC current with a curve form symmetrical to the zero axis and can switch twice the rated through-current Ir at its rated step voltage Uir. Exceeding the rated step voltage Uir for a short period by up to 10% is per- mitted if the rated through-current Ir is not exceeded. 2.2 Fundamental safety instructions 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: Personal protective equipment Loosely worn or unsuitable clothing increases the danger of becoming trapped or caught up in rotating parts and the danger of getting caught on protruding parts. This increases the danger to life and limb. ▪ All necessary devices and personal protective equipment required for the specific task, such as a hard hat, safety footwear, etc. must be worn. Ob- serve the section "Personal protective equipment" [►Section 2.4, Page 14]. ▪ Never wear damaged personal protective equipment. ▪ Never wear rings, necklaces, or other jewelry. ▪ If you have long hair, wear a hairnet. Work area Untidy and poorly lit work areas can lead to accidents. ▪ Keep the work area clean and tidy. ▪ Make sure that the work area is well lit. ▪ Observe the applicable laws for accident prevention in the relevant coun- try. Maschinenfabrik Reinhausen GmbH 2019 2159612/03 EN VACUTAP® RMV-II 11  2 Safety Limit step capacity and limit switching capacity Tap change operations with currents of more than twice the rated through- current Ir can lead to personal injuries and damage to property. The limit step capacity is the largest step capacity that can be switched safely. The on-load tap-changer can switch twice the rated through-current Ir at the rated step voltage Uir for which the on-load tap-changer was configured. ▪ Take appropriate measures to prevent tap change operations with cur- rents of more than twice the rated through-current Ir. Examples for such operating states are the inrush current impulse when transformers are switched on or a short circuit, for example. ▪ 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 occur due to overexcitation of the transformer after load shedding, for example. Working during operation The product may be operated only in a sound, operational condition. Other- wise it poses a danger to life and limb. ▪ Regularly check the operational reliability of safety equipment. ▪ Comply with the inspection work, maintenance work and maintenance in- tervals described in this technical file. Explosion protection Highly flammable or explosive gases, vapors and dusts can cause serious explosions and fire. ▪ Do not install, operate or perform maintenance work on the product in ar- eas where a risk of explosion is present. Safety markings Warning signs and safety information plates are safety markings on the product. They are an important aspect of the safety concept. ▪ Observe all safety markings on the product. ▪ Make sure all safety markings on the product remain intact and legible. ▪ Replace safety markings that are damaged or missing. Ambient conditions To ensure reliable and safe operation, the product must only be operated under the ambient conditions specified in the technical data. ▪ Observe the specified operating conditions and requirements for the in- stallation location. 12 VACUTAP® RMV-II 2159612/03 EN Maschinenfabrik Reinhausen GmbH 2019 2 Safety Auxiliary materials and operating materials Auxiliary materials and operating materials not approved by the manufac- turer can lead to personal injury, damage to property and malfunctions of the product. ▪ Only use conductive and grounded hoses, pipes, and pump equipment that are approved for flammable liquids. ▪ Only use lubricants and auxiliary materials approved by the manufacturer. ▪ Contact the manufacturer. Modifications and conversions Unauthorized or inappropriate changes to the product may lead to personal injury, material damage and operational faults. ▪ Only modify the product after consultation with the manufacturer. Spare parts Spare parts not approved by the manufacturer may lead to physical injury, damage to the product and operational faults. ▪ Only use spare parts approved by the manufacturer. ▪ Contact the manufacturer. 2.3 Personnel qualification The person responsible for assembly, commissioning, operation, mainte- nance and inspection must ensure that the personnel are sufficiently quali- fied. Electrically skilled person The electrically skilled person has a technical qualification and therefore has the required knowledge and experience, and is also conversant with the ap- plicable standards and regulations. The electrically skilled person is also pro- ficient in the following: ▪ Can identify potential dangers independently and is able to avoid them. ▪ Is able to perform work on electrical systems. ▪ Is specially trained for the working environment in which (s)he works. ▪ Must satisfy the requirements of the applicable statutory regulations for accident prevention. Electrically trained persons An electrically trained person receives instruction and guidance from an electrically skilled person in relation to the tasks undertaken and the poten- tial dangers in the event of inappropriate handling as well as the protective devices and safety measures. The electrically trained person works exclu- sively under the guidance and supervision of an electrically skilled person. Maschinenfabrik Reinhausen GmbH 2019 2159612/03 EN VACUTAP® RMV-II 13  2 Safety Operator The operator uses and operates the product in line with this technical file. The operating company provides the operator with instruction and training on the specific tasks and the associated potential dangers arising from im- proper handling. Technical Service We strongly recommend having maintenance, repairs and retrofitting carried out by our Technical Service department. This ensures that all work is per- formed correctly. If maintenance is not carried out by our Technical Service department, please ensure that the personnel who carry out the mainte- nance are trained and authorized by Maschinenfabrik Reinhausen GmbH or Reinhausen Manufacturing to carry out the work. Authorized personnel Authorized personnel are trained by Maschinenfabrik Reinhausen GmbH or Reinhausen Manufacturing to carry out special maintenance. 2.4 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. ▪ Never wear damaged personal protective equipment. ▪ Observe information about personal protective equipment provided in the work area. Personal protective equipment to be worn at all times Protective clothing Close-fitting work clothing with a low tearing strength, with tight sleeves and with no protrud- ing parts. It mainly serves to protect the wearer against being caught by moving machine parts. Safety shoes To protect against falling heavy objects and slip- ping on slippery surfaces. 14 VACUTAP® RMV-II 2159612/03 EN Maschinenfabrik Reinhausen GmbH 2019 2 Safety Special personal protective equipment for particular environments Safety glasses To protect the eyes from flying parts and splash- ing liquids. Visor To protect the face from flying parts and splash- ing liquids or other dangerous substances. Hard hat To protect from falling and flying parts and mate- rials. Hearing protection To protect from hearing damage. Protective gloves To protect from mechanical, thermal, and electri- cal hazards. Maschinenfabrik Reinhausen GmbH 2019 2159612/03 EN VACUTAP® RMV-II 15  3 Product description 3 Product description This chapter contains an overview of the design and function of the product. 3.1 Scope of delivery The product is packaged with protection against moisture and is delivered as follows: ▪ Oil compartment with in-built on-load tap-changer, tap selector and change-over selector ▪ The oil compartment is equipped with: – Oil drain valve with 2" thread for customer connection and fixture for taking oil samples – Vacuum connection: 2" half-coupling – Filler: 1" half-coupling – Terminal board with connecting lugs, each prepared with two 0.625" bores (without thread) for the customer's connection ▪ Pressure relief device MPrec ▪ Technical files Please note the following: ▪ 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 only be removed immediately before installation. 3.2 On-load tap-changer 3.2.1 Function description for on-load tap-changer RMV-II on-load tap-changers are used in conjunction with oil-immersed power transformers, regulating transformers and phase shifter transformers to change taps under load thereby controlling voltage magnitude or phase angle. The RMV-II on-load tap-changer follows the switching concept of a preven- tive auto transformer (reactor). Vacuum interrupters are used to interrupt the circuit within a half cycle. The interrupt occurs in the vacuum, so there is no shutdown arc in the oil and therefore no contamination of the oil. 16 VACUTAP® RMV-II 2159612/03 EN Maschinenfabrik Reinhausen GmbH 2019 3 Product description The diagram below shows a typical winding arrangement with the on-load tap-changer in operating position 16L: Figure 1: Typical winding arrangement of on-load tap-changer (example: operating position 16L) A, B Main switching contacts of change-over selector (example: revers- ing change-over selector) M Central position contact 3, 4, … 12 Stationary change-over selector contacts (interface to the tap leads of the tapped winding) P1, P4 Mobile change-over selector contacts VI Vacuum interrupter P2, P3 Main switching contacts for by-pass switch P Take-off terminal The tap changer operation is divided into three major functions: 1. Arc interruption and reclosing using the vacuum interrupters in conjunction with the associated by-pass switches P2 and P3 2. Selection of the next tap position by the tap selector assemblies in the correct order with actuation of the vacuum interrupters and by-pass switches 3. Operation of change-over selector (reversing change-over selector con- nection or coarse/fine selector) in order to double the number of tap posi- tions Maschinenfabrik Reinhausen GmbH 2019 2159612/03 EN VACUTAP® RMV-II 17  3 Product description The example below shows the process when changing the operating posi- tion from 16L to 15L: Figure 2: Tap changes from position 16L to position 15L The tap changer is operated using a motor-drive unit. When moving from one tap position to the next, firstly a by-pass switch (in the example P3) opens, while the second (P2) stays closed, routing the cur- rent through the vacuum interrupter just prior to its operation. The vacuum interrupter opens by a spring-operated mechanism before the mobile fine tap selector contact (in the example P4) selects the next tap. The vacuum interrupter then closes due to spring force and locks. The by- pass switch closes again, completing the tap-change operation. The tap selector connects the preventive auto transformer alternately into a bridging or a non-bridging position. The change-over selector operates only when changing from position 1 L to N or N to 1 L. For more details on the operating positions, please refer to the order-specific technical files that you received with the order confirmation. 18 VACUTAP® RMV-II 2159612/03 EN Maschinenfabrik Reinhausen GmbH 2019 3 Product description 3.2.2 On-load tap-changer design The RMV-II on-load tap changer is a three-phase on-load tap-changer with full insulation between phases and to ground. The on-load tap-changer com- prises: ▪ Tank with tap selector and change-over selector (reversing change-over selector connection or coarse/fine selector connection) ▪ By-pass switch ▪ Vacuum interrupters with monitoring system ▪ Motor-drive unit ▪ Dehydrating breather All switching elements involved in the tap-change operation, selectors and change-over selectors, vacuum interrupters and by-pass switches of all phases, are driven by one main shaft from the drive mechanism. Figure 3: On-load tap-changer oil compartment Maschinenfabrik Reinhausen GmbH 2019 2159612/03 EN VACUTAP® RMV-II 19  3 Product description One vertical insulating plate per phase is permanently mounted on the top of the on-load tap-changer oil compartment. The vacuum interrupter is mounted vertically on the front of the insulating plate. Figure 4: Vacuum interrupter The by-pass switch is located on the opposite (rear) side of the insulating plate from the vacuum interrupter and is driven by the same drive shaft. The by-pass switch consists of two contact assemblies with parallel spring- loaded contact fingers. Figure 5: By-pass switch 20 VACUTAP® RMV-II 2159612/03 EN Maschinenfabrik Reinhausen GmbH 2019 3 Product description Each phase of the on-load tap-changer also consists of a tap selector and change-over selector, which are fitted on the rear of the on-load tap-changer oil compartment on an epoxy terminal board. Figure 6: Terminal board Depending on the operating voltage of the on-load tap-changer, there are two different terminal board models. Figure 7: RMV-II 15 kV and RMV-II 26.4 kV terminal board Maschinenfabrik Reinhausen GmbH 2019 2159612/03 EN VACUTAP® RMV-II 21  3 Product description Figure 8: RMV-II 72.5 kV terminal board 3.2.2.1 Name plate The on-load tap-changer's name plate is located on the door of the on-load tap-changer oil compartment. 3.2.3 Protective devices The following protective devices for the product are included as standard in the scope of delivery or are available as options. 3.2.3.1 Pressure relief device MPreC® On request, MR will supply a pre-fitted MPreC® pressure relief device in place of the rupture disk. This device responds to a defined overpressure in the oil compartment of the on-load tap-changer. The on-load tap-changer therefore meets the requirements of IEC 60214-1 regarding pressure relief devices. 22 VACUTAP® RMV-II 2159612/03 EN Maschinenfabrik Reinhausen GmbH 2019 3 Product description 3.3 Motor-drive unit The brief description provided in this chapter is no substitute for the motor- drive unit's operating instructions. For detailed operation and safety informa- tion please read carefully through the operating instructions for the MD-III motor-drive unit. 3.3.1 Function description The motor-drive unit adjusts the operating position of on-load tap-changers in regulating transformers to the individual operating requirements. The tap-change operation is activated by starting the motor-drive unit (a sin- gle control impulse triggered, for example, by a voltage regulator of the TAPCON®-series). This operation is always completed regardless of any other control pulses emitted during the tap-change operation. In the standard design, the next tap-change operation can only proceed once all control de- vices have reached their resting positions. Behavior in the event of a voltage interruption Should the voltage be interrupted during an on-load tap-change operation, once the voltage supply returns, the motor-drive unit completes the started on-load tap-change operation. 3.3.2 Motor-drive unit design The actual motor-drive unit equipment and the arrangement of devices may differ from that shown. Maschinenfabrik Reinhausen GmbH 2019 2159612/03 EN VACUTAP® RMV-II 23  3 Product description Figure 9: View of MD-III motor-drive unit without doors 1 Motor protective switch 8-2 9 Hand lamp 2 Miniature circuit breaker (optional) 10 Voltage regulator (optional) 3 VIM-OK signal lamp (86GL) 11 Monitoring circuit board 4 Alarm signal lamp (86RL) 12 Transmission-gear cover plate 5 LOCAL/REMOTE/AUTO rotary 13 Nameplate switch 6 RAISE/LOWER control switch 14 Indication field 7 Snap latch 15 Hand crank aperture with guide lever 8 Front cover on swing frame 16 Hand crank 3.3.3 Protective devices in the motor-drive unit The following protective devices are fitted in the motor-drive unit: ▪ End stop device (mechanical and electric) ▪ Device protecting against unintentional passage ▪ Motor protection device ▪ Protection against accidental contact ▪ Electronics of monitoring system to monitor the vacuum interrupters in the on-load tap-changer 24 VACUTAP® RMV-II 2159612/03 EN Maschinenfabrik Reinhausen GmbH 2019 3 Product description 3.4 Monitoring system (VIM) The monitoring system is also known as the VIM module (Vacuum Inter- rupter Monitoring-Module). A brief description of the monitoring system can be found in this chapter. This chapter is no substitute for the detailed information provided in the sep- arate operating instructions. For detailed operation and safety information on the monitoring system, please read carefully through the operating instructions for the MD-III motor- drive unit. 3.4.1 Function description of monitoring system There is a high probability that the monitoring system will detect a vacuum interrupter malfunction in the following operating modes: ▪ Electric on-load tap-change operation resulting from manual actuation of the RAISE/LOWER rotary switch ▪ Electrical on-load tap-change operation resulting from automatic activation by a voltage regulator If the hand crank is operated, the monitoring system does not provide pro- tection. An optional mechanical hand crank lock can be used to block the hand crank in cases where the monitoring system reports a fault or is not ready for oper- ation. In the event of an error, the monitoring system triggers the following actions: ▪ The on-load tap-changer is stopped and returned to its starting position ▪ The motor protective switch 8-2 is tripped ▪ Further electrical on-load tap-change operations are blocked ▪ In designs with an appropriate hand crank lock: Hand crank operations are also blocked ▪ The error indication on the monitoring circuit board lights up – Yellow LED if there are faults in the signal transmission – Red LED should a vacuum interrupter experience an error ▪ Faults are indicated by the red Alarm indicator light (86RL) on the swing frame of the motor-drive unit lighting up. Maschinenfabrik Reinhausen GmbH 2019 2159612/03 EN VACUTAP® RMV-II 25  3 Product description 3.4.2 Monitoring system displays and controls Figure 10: Monitoring system (VIM) displays and controls 1 Green TEST push-button 3 1 yellow and 1 red LED per phase for signaling errors 2 Green Power LED 4 Red RESET push-button The following displays and controls of the monitoring system (Vacuum Inter- rupter Monitoring VIM) are located behind the motor-drive unit's door: ▪ The green TEST push-button is used to check the internal circuitry of the monitoring system. ▪ 1 green LED indicates the control voltage supply present ▪ 3 red LEDs (1 per phase) indicate when a vacuum interrupter malfunction has been recorded – The monitoring system performs this check during every diverter switch operation ▪ 3 yellow LEDs (1 per phase) indicate the loss of the current-transformer signal – The monitoring system repeats this check after every 2 tap-change op- erations for network applications and after every 32 tap-change opera- tions for industrial applications. ▪ The red RESET push-button is used to activate the monitoring system af- ter an inspection. 3.5 Dehydrating breather The dehydrating breather removes moisture from the air breathed into the on-load tap-changer. The dehydrating breather comprises: ▪ Glass cylinder ▪ Connecting flange on top ▪ Breather ▪ Protective grate with viewing windows 26 VACUTAP® RMV-II 2159612/03 EN Maschinenfabrik Reinhausen GmbH 2019 3 Product description By way of an option, we recommend using the maintenance-free MTraB® DB 100 dehydrating breather from Maschinenfabrik Reinhausen GmbH. Upon delivery The breather is supplied dismantled with the drying agent placed in separate containers. Maschinenfabrik Reinhausen GmbH 2019 2159612/03 EN VACUTAP® RMV-II 27  4 Packaging, transport and storage 4 Packaging, transport and storage 4.1 Packaging The products are sometimes supplied in a sealed packaging and sometimes in a dry state depending on requirements. A sealed packaging surrounds the packaged goods on all sides with plastic foil. Products that have also been dried are identified by a yellow label on the sealed packaging. The information in the following sections should be applied as appropriate. 4.1.1 Suitability NOTICE Property damage due to incorrectly stacked crates! Stacking the crates incorrectly can lead to damage to the packaged goods. ► Only stack up to 2 equally sized crates on top of one another. ► Do not stack crates above a height of 1.5 m. The packaging is suitable for undamaged and fully functional means of transportation in compliance with local transportation laws and regulations. The packaged goods are packed in a sturdy crate. This crate ensures that, when in the intended transportation position, the packaged goods are stabi- lized to prevent impermissible changes in position, and that none of the parts touch the loading surface of the means of transport or touch the ground after unloading. A sealed packaging surrounds the packaged goods on all sides with plastic foil. The packaged goods are protected from humidity using a desiccant. The plastic foil is bonded after the desiccant is added. 4.1.2 Markings The packaging bears a signature with instructions for safe transport and cor- rect storage. The following symbols apply to the shipment of non-hazardous goods. Adherence to these symbols is mandatory. Protect against Top Fragile Attach lifting Center of mass moisture gear here Table 3: Shipping pictograms 28 VACUTAP® RMV-II 2159612/03 EN Maschinenfabrik Reinhausen GmbH 2019 4 Packaging, transport and storage 4.2 Transportation, receipt and handling of shipments WARNING Danger of death and damage to property! Danger of death and damage to property due to tipping or falling load. ► Only transport the crate when closed. ► Do not remove the securing material used in the crate during transport. ► If the product is delivered loose on a pallet, secure it sufficiently. ► Only trained and authorized persons may select the sling gear and se- cure the load. ► Do not walk under the hanging load. ► Use means of transport and lifting gear with a sufficient carrying capacity in accordance with the weight stated on the delivery slip. In addition to oscillation stress, jolts must also be expected during trans- portation. In order to prevent possible damage, avoid dropping, tipping, knocking over and colliding with the product. If a crate tips over, falls from a certain height (e.g. when slings tear) or is subject to an unbroken fall, damage must be expected regardless of the weight. Every delivered shipment must be checked for the following by the recipient before acceptance (acknowledgment of receipt): ▪ Completeness based on the delivery slip ▪ External damage of any type The checks must take place after unloading when the crate or transport con- tainer can be accessed from all sides. Visible damage If external transport damage is found on receipt of the shipment, proceed as follows: ▪ Immediately record the transport damage found in the shipping docu- ments and have this countersigned by the carrier. ▪ In the event of severe damage, total loss or high damage costs, immedi- ately notify the manufacturer and the relevant insurance company. ▪ After identifying damage, do not modify the condition of the shipment fur- ther and retain the packaging material until an inspection decision has been made by the transport company or the insurance company. ▪ Record the details of the damage immediately on site together with the carrier involved. This is essential for any claim for damages. ▪ Photograph damage to packaging and packaged goods. This also applies to signs of corrosion on the packaged goods due to moisture inside the packaging (rain, snow, condensation). ▪ NOTICE! If the product is delivered in sealed packaging, inspect this im- mediately. If the sealed packaging is damaged, do not under any circum- stances install or commission the packaged goods. Either re-dry the dried Maschinenfabrik Reinhausen GmbH 2019 2159612/03 EN VACUTAP® RMV-II 29  4 Packaging, transport and storage packaged goods as per the operating instructions, or contact the manu- facturer to agree on how to proceed. Failure to do so may result in dam- age to the packaged goods. ▪ Identify the damaged parts. Hidden damage When damages are not determined until unpacking after receipt of the ship- ment (hidden damage), proceed as follows: ▪ Make the party responsible for the damage liable as soon as possible by telephone and in writing, and prepare a damage report. ▪ Observe the time periods applicable to such actions in the respective country. Inquire about these in good time. With hidden damage, it is very hard to make the transportation company (or other responsible party) liable. Any insurance claims for such damages can only be successful if relevant provisions are expressly included in the insur- ance terms and conditions. 4.3 Unpacking shipments and checking for transportation damages ▪ NOTICE! Transport the packaged crate to the place where installation will take place. Do not open the sealed packaging until just before installation. If this is not done, damage to the packaged goods may occur due to inef- fectively sealed packaging. ▪ WARNING! When unpacking, check the condition of the packaged goods.Secure packaged goods in an upright crate from tipping out. If this is not done, the packaged goods may be damaged and serious injuries may result. ▪ Check completeness of supplementary parts on the basis of the delivery slip. 4.4 Things to note when putting back into storage The on-load tap-changer is shipped from Reinhausen Manufacturing filled with dry nitrogen under positive pressure. NOTICE Damage caused by storage in unheated buildings or outdoors If the on-load tap-changer and drive are to be stored in unheated buildings or outdoors: ► Fill on-load tap-changer tank with clean, dry oil and refill gas space with dry nitrogen to a maximum pressure of 0.275 bar (4 psi). ► Weather-proof outside of tank and terminal board. ► Heat drive by connecting the built-in space heater to power. 30 VACUTAP® RMV-II 2159612/03 EN Maschinenfabrik Reinhausen GmbH 2019 5 Fitting on-load tap-changer on transformer 5 Fitting on-load tap-changer on transformer This chapter describes how to fit the on-load tap-changer to a transformer. 5.1 Preparatory work Perform the work stated below before fitting the on-load tap-changer to the transformer: ▪ Before mounting on the transformer, open the on-load tap-changer's oil compartment and the drive mechanism air compartment and inspect for damage which may have occurred in shipment due to rough handling. ▪ If shipment damage is found, immediately raise a complaint with the sup- plier and inform Reinhausen Manufacturing Inc.. ▪ Note the general information about the transformer. 5.2 Fitting the on-load tap-changer NOTICE Damage to the on-load tap-changer caused by heat when weld- ing! Welding adjacent to the epoxy terminal board may distort its mounting sur- face and cause damage to the terminal board or its oil seal. ► Use suitable shielding to protect components near welding from radiant heat. 1. Check the size of the opening in the transformer's main tank. For mini- mum tank opening dimensions, see order-specific dimensional drawing. 2. Weld on-load tap-changer oil compartment onto transformer's main tank. Ensure the welded seam is oil-tight, pressure-tight and vacuum-proof. Mount the on-load tap-changer on a transformer tank wall that is designed to withstand normal test and operating pressures (at least 15 psi (1 bar)). A 0.25" oil-tight welded seam is required around the outside perimeter of the on-load tap-changer mounting flange. No welded seam is required on the transformer side of the on-load tap-changer. Maschinenfabrik Reinhausen GmbH 2019 2159612/03 EN VACUTAP® RMV-II 31  5 Fitting on-load tap-changer on transformer 5.3 Connecting the tap winding and on-load tap-changer take- off lead NOTICE Damage to the on-load tap-changer! Connecting leads that place mechanical strain on the on-load tap-changer will damage the on-load tap-changer. ► Establish connections carefully. ► Do not twist connection contacts. ► Connect connecting leads without warping or deforming. ► If necessary, use an expansion loop for connecting leads. ► Fit screening caps provided to screw connections. The tap winding and on-load tap-changer take-off lead must be connected in accordance with the connection diagram included with the delivery. 32 VACUTAP® RMV-II 2159612/03 EN Maschinenfabrik Reinhausen GmbH 2019 6 Fitting motor-drive unit 6 Fitting motor-drive unit 6.1 Preparatory work WARNING The motor-drive unit may be started by accident if the motor protective switch is not tripped! Risk of injury from starting the motor-drive unit by accident! ► Trip motor protective switch before starting to fit the drive shafts! NOTICE Damage to on-load tap-changer and motor-drive unit due to in- correct operation! The on-load tap-changer and motor-drive unit are shipped on separate pal- lets in the neutral position. Prior to assembly check the serial numbers of the on-load tap-changer and motor-drive unit to ensure they belong to- gether. If the on-load tap-changer and motor-drive unit are not connected, mechani- cal damage will result from both the drive shaft of the on-load tap-changer turning and the output shaft of the motor-drive unit turning! ü Prior to shipment the on-load tap-changer is locked in the neutral position by a cotter pin. This cotter pin is inserted through the hub and drive shaft extension on the bottom of the tank. It may only be removed just before assembly. Keep the cotter pin. ► Check the neutral position on the on-load tap-changer and motor-drive unit as described below. ► Only join shafts that have been perfectly aligned. ► If you detect deviations, contact Reinhausen Manufacturing. Maschinenfabrik Reinhausen GmbH 2019 2159612/03 EN VACUTAP® RMV-II 33  6 Fitting motor-drive unit Checking neutral position Check the on-load tap-changer's neutral position with the door open as fol- lows: 1. Both change-over selector contacts are in the top position. Figure 11: Change-over selector contacts 34 VACUTAP® RMV-II 2159612/03 EN Maschinenfabrik Reinhausen GmbH 2019 6 Fitting motor-drive unit 2. The adjustment markings on the by-pass switch are aligned to one an- other. Figure 12: Adjustment markings on the by-pass Check the motor-drive unit's neutral position as follows: 1. The tap position indicator is at neutral. 2. The pointer on the the tap-change indicator is in the mid-position of the area marked in gray. Figure 13: Indication field Maschinenfabrik Reinhausen GmbH 2019 2159612/03 EN VACUTAP® RMV-II 35  6 Fitting motor-drive unit Assembly variants When assembling the motor-drive unit, a distinction is made between 2 vari- ants: 1. Standard assembly means that the motor-drive unit is fitted directly be- neath and secured to the on-load tap-changer. 2. Offset assembly (assembly on the floor) means that there is a gap be- tween the motor-drive unit and the on-load tap-changer beneath which it is fitted and that the motor-drive unit is secured to the transformer on the main tank. This variant requires a mounting support on the main trans- former tank, which is provided by the transformer manufacturer. 6.2 Fitting motor-drive unit to on-load tap-changer For detailed information on fitting and the electrical connection, please refer to the motor-drive unit's operating instructions. 36 VACUTAP® RMV-II 2159612/03 EN Maschinenfabrik Reinhausen GmbH 2019 7 Checks after assembly 7 Checks after assembly Please contact Reinhausen Manufacturing if any aspect of the tests is not clear. 7.1 Manual check For the manual check, open the on-load tap-changer oil compartment and motor-drive unit. Three insulating material plates are arranged vertically next to one another in the front of the on-load tap-changer oil compartment. The vacuum interrupters are each mounted on the front of the insulating material plates. The by-pass switches are on the rear of the insulating material plates. The tap selector and change-over selector are fitted in the rear sec- tion of the oil compartment on the epoxy terminal board, see On-load tap- changer design [►Section 3.2.2, Page 19] chapter. 1. Switch off motor protective switch 8-2. 2. Insert hand crank in hand crank aperture on motor-drive unit. 3. Use hand crank to switch from Neutral N to 1L. To do this, turn the hand crank counter-clockwise 7.5 revolutions. Check how the on-load tap- changer is undertaking tap changes (the changeover takes place syn- chronously in all three phases): ð First, the by-pass switch P2 has to open, then the vacuum interrupter opens. ð The tap selector contact P1 (closest to the terminal board) now moves from M to 11. At the same time, the change-over selector moves from B to A. Make sure that the mobile contacts of the tap selector and change-over selector run smoothly and freely. ð Next, the vacuum interrupter contact closes again. ð Lastly, observe closure of the by-pass switch P2. Once the 7.5 hand crank revolutions are complete, the on-load tap-changer's changeover to the new operating position 1L is complete. 4. Now use the hand crank to switch back into Neutral (N). ð The switching processes should take place in the order outlined above except that the tap selector moves from 11 to M and the change-over selector moves from A to B. Maschinenfabrik Reinhausen GmbH 2019 2159612/03 EN VACUTAP® RMV-II 37  7 Checks after assembly The same check now has to be performed in the other switching direction. 1. Use hand crank to switch from operating position N to 1R. Again check how the on-load tap-changer undertakes the tap change: ð First the by-pass switch P3 and then the vacuum interrupter must open. ð The tap selector contact P4 (furthest away from the terminal board) now moves from M to 4. The change-over selector does not move this time. Ensure that the tap selector's mobile contact is again running smoothly and freely. ð Next, the vacuum interrupter contact closes again. ð Lastly, observe closure of the by-pass switch P3. Once the 7.5 hand crank revolutions are complete, the on-load tap-changer's changeover to the new operating position 1R is complete. 2. Now use the hand crank to switch back into Neutral (N). ð The switching processes should take place in the order outlined above except that the tap selector moves from 4 to M. 3. Withdraw the hand crank and place it in the storage holder provided. 4. Close protective housing of the motor-drive unit. 5. Close oil compartment of the on-load tap-changer. Tighten nuts on access door to on-load tap-changer to a maximum tighten- ing torque of 11 ft·lb (15 Nm)). 7.2 Checking motor-drive unit and monitoring system Before further checks on the on-load tap-changer and transformer, check that the motor-drive unit and monitoring system are functioning correctly. A detailed description of this can be found in the operating instructions for the motor-drive unit. 7.3 Transformer ratio test and DC resistance measurement NOTICE Damage to the on-load tap-changer! Performing too many operations without complete oil filling will damage the on-load tap-changer! ► Do not perform more than 120 tap-change operations on the on-load tap- changer. ► Before operating for the first time after drying, the on-load tap-changer must be filled with oil up to the corresponding mark. 38 VACUTAP® RMV-II 2159612/03 EN Maschinenfabrik Reinhausen GmbH 2019 7 Checks after assembly NOTICE Damage to motor-drive unit! Too many tap-change operations in succession will damage the motor! ► Perform no more than 120 tap-change operations in succession to avoid damaging the motor. 7.3.1 Carrying out the transformer ratio test We recommend carrying out a transformer ratio test before the transformer is dried. 1. NOTICE! Carry out the transformer ratio test in all operating positions. Never overshoot the end positions, which are indicated in the connection diagram supplied with the delivery. 2. Once the transformer ratio test is complete, return on-load tap-changer to its adjustment position (see supplied connection diagram of the on-load tap-changer). 7.3.2 Measuring DC resistance on transformer Note the measurement scenarios listed below and the associated maximum measured currents when measuring DC resistance on the transformer. The measured DC current is normally restricted to 10 % of the rated current of the measured transformer winding in order to prevent the winding from overheating. Measure the DC resistance in the various on-load tap-changer operating po- sitions. You need to distinguish here whether the measured current is inter- rupted when changing operating position or not. Without interruption in With interruption (mea- measured current sured current = 0 A be- fore change in operating position) Oil compartment empty Maximum 10 A DC Maximum 50 A DC Oil compartment filled with Maximum 50 A DC Maximum 50 A DC insulating oil Table 4: Maximum permitted measured currents when measuring DC resistance on transformer Maschinenfabrik Reinhausen GmbH 2019 2159612/03 EN VACUTAP® RMV-II 39  8 Drying the on-load tap-changer 8 Drying the on-load tap-changer NOTICE Damage to on-load tap-changer accessories! Rapid changes in pressure during the drying process and the oil fill can damage the on-load tap-changer accessories! ► Remove on-load tap-changer accessories, such as dehydrating breather and pressure relief devices, before drying and filling with oil. A prerequisite for the dielectric values assured by MR for the on-load tap- changer is a minimum drying procedure performed following the instructions below and that the on-load tap-changer is treated as pat of the transformer during the drying process. 1. Remove on-load tap-changer accessories, such as dehydrating breather and pressure relief devices, before drying and seal the connection points. 2. Connect on-load tap-changer and transformer gas spaces through the vent plug. ð There is no difference in pressure between the on-load tap-changer oil compartment and transformer tank during the drying process, not even at the terminal board and sealing system. 3. Heat up the on-load tap-changer in air at atmospheric pressure with a temperature increase of about 10 K/h to a final temperature of maximum 110 °C. 4. Pre-dry the on-load tap-changer in circulating air at a max. temperature of 110 °C for a period of 20 hours. 5. Vacuum dry on-load tap-changer at between 105 °C and maximum 110 °C. Residual pressure of no more than 10-3 bar [0.75 Torr/0.015 psi]. The drying period depends on the drying period of the transformer but should be at least 50 hours. 6. Always break the vacuum with dry, inert gas to prevent moisture contami- nation. The on-load tap-changer is designed for a full vacuum without any limitation on use. The terminal board is designed to withstand a maximum differential pressure of 1241 mbar [931 Torr/18 psi]. This allows for a full vacuum in the on-load tap-changer's oil compartment with a maximum positive pressure of 227 mbar [171 Torr/3.3 psi] on the transformer side of the terminal board. 40 VACUTAP® RMV-II 2159612/03 EN Maschinenfabrik Reinhausen GmbH 2019 9 Filling on-load tap-changer with oil 9 Filling on-load tap-changer with oil Before applying operating voltage, the on-load tap-changer oil compartment must be filled with oil to the corresponding mark under a vacuum. To do so, proceed as follows: 1. Make the oil input and vacuum connections to the oil compartment. Re- move ¼" coupling and connect to the dehydrating breather. 2. 2 hours before and during filling, maintain a vacuum of less than 1.33 mbar [1 Torr/0.02 psi] on the on-load tap-changer oil compartment. ð Degassed oil will facilitate this process. 3. Break the vacuum with dry, inert gas. 4. Take 3 oil samples from the oil compartment of the on-load tap-changer. Determine dielectric strength and water content at oil temperature of 20 °C ± 5 °C. ð The dielectric strength and water content must comply with the limit val- ues provided in the appendix [►Section 19.1, Page 70]. 5. Use motor-drive unit to switch on-load tap-changer across entire range from 16 L to 16 R and then leave de-energized for an hour. ð The gas bubbles break up in the oil. 6. Close on-load tap-changer oil compartment openings. Maschinenfabrik Reinhausen GmbH 2019 2159612/03 EN VACUTAP® RMV-II 41  10 Fitting accessories 10 Fitting accessories 10.1 Fitting dehydrating breather Figure 14: Mounting dehydrating breather 42 VACUTAP® RMV-II 2159612/03 EN Maschinenfabrik Reinhausen GmbH 2019 10 Fitting accessories To mount the dehydrating breather, proceed as follows: 1. Fill chamber of dehydrating breather with dry drying agent through flange opening on top (approx. 2.2 lb (1 kg)). 2. Place flange gasket on flange and position retaining plate. The tapped hole and flange opening must be in line. Secure with two M10 x 35 hex bolts, washers and locking nuts. 3. Fit dehydrating breather chamber on mounting pad (provided by cus- tomer) on wall of transformer tank. See sketch A (see above) for recom- mended mounting pad dimensions. Secure with two M10 x 35 hex bolts, washers and locking nuts. 4. Connect tubing between top of dehydrating breather and one of the 0.25" half couplings on the on-load tap-changer side walls. All connections must be air tight. Use of a high temperature grease on the screw joints helps prevent rust and permits the parts to be removed easily when necessary. Maschinenfabrik Reinhausen GmbH 2019 2159612/03 EN VACUTAP® RMV-II 43  10 Fitting accessories 5. Remove the clear plastic oil compartment by squeezing the retaining brackets. Fill it with clean transformer oil until the oil level is between the two fill level lines on the compartment. Carefully place the filled oil com- partment back onto the dehydrating breather housing bottom. Figure 15: Dehydrating breather 1 3/8" union nut 4 Protective grate 2 Retaining plate 5 Oil collection container 3 Mounting block (secured to trans- 6 Fill-level mark former wall) 10.2 Pressure relief device MPreC® For detailed information about the pressure relief device, please refer to the relevant operating instructions. Ensure that the relevant circuit breaker immediately de-energizes the trans- former as soon as the pressure relief device or any other protective device triggers. To do this, loop one signaling contact into the tripping circuit of the circuit breaker for each protective device. 44 VACUTAP® RMV-II 2159612/03 EN Maschinenfabrik Reinhausen GmbH 2019 11 Commissioning at the transformer manufacturer's site 11 Commissioning at the transformer manufacturer's site WARNING Danger of death or severe injury! Danger of death or severe injury from explosive gases in the on-load tap- changer, in the pipework system, at the dehydrating breather opening and from flying parts and hot oil splashing! ► Make sure that only trained technicians perform work on the transformer. ► Use suitable personal protective equipment/clothing. ► Ensure that there are no naked flames, hot surfaces or sparks (for exam- ple caused by static charging) in the immediate surroundings and that none occur. ► Only use conductive and grounded hoses, pipes, and pump equipment that are approved for flammable liquids. ► Ensure that the oil compartment of the on-load tap-changer is correctly filled with oil as per the instructions. ► Ensure that all the on-load tap-changer's safety equipment is ready for use. ► Keep away from the danger area during the transformer test. ► Observe applicable fire protection regulations. WARNING Danger of death and damage to property! Danger of death and damage to property due to incorrect operation during commissioning! ► Only start up transformer if the functions described in the Checks after assembly [►Section 7, Page 37] chapter are satisfied. ► Only actuate on-load tap-changer with the hand crank if the transformer is de-energized and the motor protective switch switched off. ð Otherwise damage to the transformer and/or personal injury may result if any of the vacuum interrupters fails to interrupt. ► During operation, if the monitoring system trips, do not reset until the on- load tap-changer has been inspected and the cause of the problem cor- rected. ► Contact Reinhausen Manufacturing for assistance if needed.