Suva-AVR Service 2012.docx

STATEMENT OF WORK

Medium Voltage Equipment and Systems Safety Inspection, Assessment, and Commissioning Services Power Systems Support Program Overseas Building Operations

1.0 INTRODUCTION. This is a firm fixed price contract for onsite services at the American Embassy compound Suva. All proposal packages must be accompanied with a work plan and projected site visit dates for all listed tasks within this work statement. The various locations can be performed in any order and they do not necessarily have to be accomplished on the same swing. All site visits and scope work must be completed no later than May 15, 2012, this includes after visit reports. The following outlined scope is considered phase-one support and is solicited as a one-time service visit. Subsequent phases and site work will be addressed in a separate work statement. Site locations and specific equipment details are listed below:

A) Suva, Fiji: (embassy compound) Three VR-32 tanks, Cooper Power Systems, 11 KV, 150/168 KVA, Model # WAG15B54S5J, Serial numbers: 0850008905, 0850008906, and 0850008907

2.0 SCOPE OF WORK. The purpose of this SOW is to secure the materials and qualified labor required for successful completion of the following work at the listed embassy location. All performing technicians and engineers must be trained to comply with OSHA CFR1910.269 Electrical Safety Std for HV systems >600V, and NFPA 70E. This effort is to ensure that the electrical distribution equipment and voltage regulator system at each of these facilities were correctly installed within 2007 National Electrical Code requirements and NFPA 70E standards, and functioning as designed providing regulated power to the designated load. The final inspection summary must outline site conditions, noted discrepancies, proper clearances, operational functionality, and related safety concerns. Provide retro-commissioning to ensure all controls are set per the unit nameplate and regulating within a time delay and bandwidth suitable for the host country conditions. This entire work statement, each portion or step, applies to each individual MV tank at all listed locations. This site maintenance includes, but is not limited to, the following steps in 2.0.1 and 2.1 of this work statement.

2.0.1 AUTOMATIC VOLTAGE REGULATOR & MV SWITCHGEAR (steps 1-28)

1. Meet with the embassy Facility Manager to coordinate all scheduled work and inspections. Contractor personnel must familiarize themselves with site power conditions, related compound power problems, and post power concerns. Verify existing distribution one-line drawing and equipment installed for accuracy, submit corrections as necessary.

2. Ensure post generator system and auto-transfer switch are operational, set for emergency stand-by automatic start, and transfer prior to starting any AVR testing. Ensure adequate fuel levels in the generator day tanks.

3. Follow all manufacture recommended safety practices and safety requirements. Have on hand an electrical approved fire extinguisher, and all applicable PPE for the rated voltages. Refer to NFPA 70 E, page-34 table 130.7 C 9, for guidelines regarding arc-flash PPE.

4. Survey the Embassy owned arc-flash PPE and testing tools. Provide a site specific BOM for recommended and required safety equipment that post does not have on hand; include part numbers, retail price, and a supply source for each item, such as (Cat-3 suit, hot-stick with proximity tester, ground cluster, etc. )

5. Schedule a system outage and coordinate the switch-over to post generator power with the site Facility Manager. Once post load is isolated, shut down, tag-out and lock all incoming MV circuits and place personal safety grounds prior to conducting any offline checks.

6. Perform a visual inspection of the entire Medium Voltage distribution system to include the AVR, Output transformer, Demark disconnect, distribution cables, outdoor bus structures and Medium Voltage open air switches, step-down transformers, fuse holders, terminals, insulators, lighting arrestors, etc. Clean, adjust, and lubricate as required.

7. Correct any minor deficiencies found using post material and provide two separate and site specific BOMs for each post. One BOM for any needed repair material not presently on site (as applicable), and the second BOM is based on post’s existing spares kit and your recommendations for any additional AVR spare parts; such as fuses, capacitors, and control panels. Both BOMs must note the material names, part numbers, price and source.

8. Inventory and record nameplate data of all medium voltage electrical equipment. Take photographs, record input and output voltage and amperage levels. Create a medium voltage equipment list for each embassy location.

9. Record the status of the AVR control panel switches, and all function code settings.

10. Perform a transformer turn-ratio (TTR) test for each regulator step, and conduct a full system meg-ohm meter test. All tasks are to be performed without untanking the regulator.

11. Clean the total interior of the AVR enclosure, wiring and tank assemblies.

12. Verify proper control panel programming and system operation, record findings, correct any noted deficiencies. With external control power follow steps of the manufacture’s manual to perform all in-service operational checks, field calibration checks, and manual mode steps.

13. Program and activate function 80-81-82 on Cooper AVR systems.

14. Program the control panel function codes to match nameplate settings and adjust the reference voltage to best regulate near the AVR neutral position. This will ensure that normal fluctuations take the tap position across a neutral reference as much as possible.

15. Ensure the MV transformer voltage output matches within 3% of the site diesel generator voltage output. Change the MV output transformer tap if necessary.

16. Draw oil samples on the medium voltage transformer. Perform electrical tests and dissolved gas analysis (DGA) per NETA and manufacturer procedures and perform PCB screening. Measure and record transformer oil levels and nitrogen pressures per NETA and manufacturer procedures.

17. Take oil samples on all three regulator tanks and conduct all testing except for dissolved gas analysis.

18. The contractor shall perform all work to determine latent and obvious problems or deficiencies pertaining to equipment, systems and apparatus safety hazards or safety code non-compliance, operational failure or inability for equipment to perform and provide the intended service level or functionality, reliability or usability.

19. Provide for each post and include in the final report a post specific Standard Operating Procedure (SOP) for tag-out isolation of the AVR.

20. Provide for each post and include in the final report a post specific SOP for control panel replacement noting the site specific settings that must be programmed when replacing a control panel.

21. Provide training to one or more embassy representatives on unit operation and safety concerns. Provide training using the site specific SOPs to demonstrate proper AVR isolation and lock-out procedures required for any maintenance action on the AVR. Train on the SOP for control panel replacement. Emphasize that all AVR bypass switching, cleaning, and control panel replacements are to be performed with the AVR de-energized. Discuss during training other electrical safe work practices such as lock-out/tag-out of an ATS or Switchgear isolation. Training shall be given until the representatives have an adequate comfort level with the unit’s operation and maintenance SOPs, not to exceed 6 hours.

22. Label with P-touch white label with black letters the following on the inside door of each completed controller: PM performed by (company name) via OBO/CFSM/FAC/MS on (date). For service contact Aldenjn@state.gov.

23. Reenergize system and restore to automatic operation unless a noted safety concern exists. Call and email James Alden (703-875-6190, AldenJN@state.gov); Richard Crowson (703-337-7156, rcrowson@hotmail.com), immediately upon notice of a hazardous situation pre-existing or caused by this work.

24. Perform infrared (IR) scanning and inspection of all energized MV equipment per NETA, thermographic survey procedures and guidelines.

25. After all control panel settings and corrections are made connect monitoring equipment, similar to “Power Site 4000” or equal, on the secondary side of the MV transformer. Monitor AVR output power and commercial power frequency fluctuations for 24-hours after the AVR is returned to service. Evaluate based on observations while on-site the level of fluctuations seen on the incoming city power on the MV side of the transformer. Ensure the AVR is regulating within its capabilities.

26. Send out a summary Email to the following addresses prior to site departure: aldenjn@state.gov. Provide in this email summary the AVR status, as well as the present condition of the compound diesel generators, to include nameplate data, number of starts, and operational hours.

27. Complete an AVR summary sheet and submit within 10-days of site visit completion. Contact the COR if you do not have a sample of the AVR summary sheet.

28. Out-brief/Final Report: Meet with site Facility Manager regarding the condition of the regulators, operational status, safety concerns, and general findings. Discuss the MV system with Post FM and LES maintenance staff to determine what level of medium voltage expertise exists at Post. Note any known maintenance and repair actions performed on the MV system prior to this baseline PM service visit. Report these findings in the executive summary.

2.1 MV TRANSFORMER AND SWITCHGEAR INSPECTION (As applicable)

2.1 Exterior

2.1.1 Ensure that the nameplate data is legible.

2.1.2 Ensure that the third party listing service label is legible.

2.1.3 Inspect the overall exterior for missing screws, bolts, nuts, fasteners, retainers and keepers.

2.1.4 Inspect for unused openings.

2.1.5 Inspect for improper covers.

2.1.6 Inspect for erosion and corrosion.

2.1.7 Inspect all lugs for signs of overheating and missing or defective parts.

2.1.8 Inspect insulation structure for signs of overheating and tracking and deterioration.

2.1.9 Inspect for proper alignment of each cubicle section.

2.1.10 Check that all cabinets are level, plumb and square.

2.1.11 Inspect all oil filled compartments, gaskets, seals, etc. for oil leakage. Inspect primary and secondary bushing for oil leakage.

2.1.12 Inspect and check for proper phase to phase and phase to ground spacing clearances between metal parts.

2.1.13 Inspect and check all dial indicators, position indicators, etc. for proper operations, damages, connection and function.

2.1.14 Inspect and check all external cooling fans and pumps for proper operation, setting, installation, signs of mechanical or electrical damages, leaks, etc. verify proper over-current protection and starting controls are in place and installed correctly.

2.1.15 Verify correct liquid level for all oil filled compartments and bushings.

2.1.16 Verify that positive pressure is maintained on nitrogen blanketed transformers, as applicable.

2.1.17 Verify that the transformer is properly grounded.

2.1.18 Verify and inspect transformer surge arrestors for proper installation, signs of damage (electrical or mechanical), insulation failure, e.g. tracking or corona.

2.1.19 Record results.

2.2 Panel Indicators

2.2.1 Check all lens covers for damages, cracks, moisture

accumulation, etc...

2.2.2 Check all indicating lamps for operation.

2.2.3 Inspect all control wiring.

2.2.4 Record results.

2.3 Bushings, Support/Insulation

2.3.1 Inspect for signs of electrical short circuit/overload damages, overheating, tracking/corona, etc.

2.3.2 Inspect for signs of deterioration, corrosion, erosion, fatigue, overload, tracking/corona, etc.

2.3.3 Inspect for chips, cracks and broken insulators, tracking/corona, etc.

2.3.4. Verify that all bus insulation and supports are properly rated and installed for applied service voltage, including BIL.

2.3.5 Inspect bushing for oil leakage/damage.

2.3.6 Record results

2.4 Control Circuits

2.4.1 Inspect all control wiring

2.4.1.1 Inspect for signs of deterioration, corrosion, fatigue or overload.

2.4.1.2 Inspect for signs of overheating, burnt or frayed insulation.

2.4.1.3 Inspect for loose connections, repair any found.

2.4.2 Check all functions of control and test switches, verify proper operations and that operational sequences operate normally.

2.4.3 Check all interconnect wiring and terminal blocks for insulation/conductor damages, tightness, etc.

2.4.4. Check and inspect all protective relays, including pressure relief devices for proper setting, improper application, missing or damaged components. Check relays for any operational/tripping flags.

2.4.4 Verify accuracy and legibility of all applicable wiring schematics and drawings.

2.4.5 Record results.

2.5 Cabinets/Cubicles

2.5.1 Inspect and clean all interior cabinet surfaces, check for component and hardware damages, missing components, improper components, etc.

2.5.2 All compartment space heaters shall be inspected for damages and proper operation, including associated power or control wiring, thermostats, etc.

2.5.3 Check all auxiliary switches and contactors for proper operation.

2.5.4 Check and inspect all control wiring as noted/required herein.

2.5.5 Check and inspect any control power circuit breakers and fuses, including fuse holders for damages, signs of electrical failure, overheating, tracking/corona and check/inspect all connected wiring and inspect terminals for proper torque/tightness.

2.5.6 Check operation of all jack screw and racking mechanisms, lubricate as needed.

Clean and inspect all interior breaker and cubicle surfaces, check for component and hardware damage, or missing components. Check all auxiliary and cell switches, space heaters and control wiring.

2.5.7 Record results.

2.8 Devices - Low Voltage Control and Instrument Transformers & Metering

2.8.1.1 Inspect nameplate data and compare against design drawings for proper application and function.

2.8.1.2. Inspect and check all insulating systems and barriers for damages, tracking or corona, broken or missing components, damaged or missing hardware.

2.8.1.3 Verify proper connection of each device, including any ground connections, verify proper terminal tightness/torque, and verify that wiring is maintained for proper electrical clearance.

2.8.1.4. As applicable, verify correct operation of transformer withdrawal devices, racks, mechanisms, etc. See Circuit Breaker section.

2.8.1.5 Verify proper polarities are maintained.

2.8.1.6 Inspect all metering devices for damaged and proper cover gaskets, lens, and freedom of movement, check all connected control wiring, and refer to control circuits. Check all meter accuracy and function with appropriate test equipment.

2.8.1.7 Record results

2.8.2. Protective Relays, Pressure Relief Devices

2.8.2.1 Inspect nameplate data and compare against design drawings for proper application and function.

2.8.2.2 Inspect all relays for component damages, broken or missing parts, damaged lens, broken or missing hardware, etc.

2.8.2.3 Inspect and check all insulating systems and barriers for damages, tracking or corona, broken or missing components, damaged or missing hardware.

2.8.2.4 Verify proper connection of each device, including any ground connections, verify proper terminal tightness/torque, and verify that wiring is maintained for proper electrical clearance.

2.8.2.5 Check, inspect and clean all relays, external and internal, remove any debris found, verify free movement of all internal components, inspect contacts for signs of wear, arching, etc.

2.8.2.6 Check all relay setting and verify settings against time over current/short circuit study, reset settings as required.

2.8.2.7 Inspect, check and operate each oil filled compartment pressure relay. Ensure pressure relay operates at listed/rated pressure setting.

2.8.2.8 Verify operation of all alarm, control and trip circuits from temperature and level indicators and fault pressure relay, if applicable.

2.8.2.9 Record results.

2.8.3 Tap Changer (No-Load and Load)

2.8.3.1 Verify proper operation of tap changer; operate switching mechanism at each step, raise and lower.

2.8.3.2 Verify and inspect that any tap changing indicators are function and register the correct tap position.

2.8.3.3. Record results

2.8.4 Switchgear Bus

2.8.4.1 Inspect phase and ground bus for proper connection, torque, hardware, signs of overheating.

2.8.4.2 Check for continuous current carrying path on all bus, check for proper insulation, clearance and rating.

2.8.4.3 Inspect for signs of short circuit, overload damages, overheating, and tracking/corona. Inspect for signs of deterioration, corrosion, erosion, fatigue of support and insulation.

2.8.4.4 Record results.

2.8.5 Interlocks

2.8.5.1 Check all cabinets for interlock function, including positive, negative and racking interlocks. Check all key operated interlock systems for proper function.

2.8.5.2 Record results

3.0 WORK STANDARDS. This Statement of Work requires the awarded contractor to provide a technician qualified on COOPER POWER SYSTEMS voltage regulators with factory training/experience; additionally provide a certified representative, and other qualified personnel, and engineering support to assess, inspect, test, perform PM, conduct hazards and safety analyses, commission and perform factory start up services for medium voltage electrical systems, apparatus and equipment located worldwide. All performing technicians and engineers must be trained to comply with OSHA CFR1910.269 Electrical Safety Std for HV systems >600V. The contractor shall furnish all tools, test equipment, required arc-flash PPE, and properly supervise all site personnel who are trained and qualified to work on medium voltage equipment, systems. Working voltage for the equipment under this statement of work is between 10KV to 33KV, line to line. Contractor personnel, as applicable, shall be factory trained and certified to perform work. In lieu of factory certifications, contractor personnel who possess prior experience with working on and operating both GE and Cooper AVR equipment will be considered. If the contractor desires to supplement factory certifications with hands on experience, the contractor shall submit with their proposal personnel qualification statements describing the type of work performed, equipment worked, duration of work, references and any additional training certificates, licensure, etc. that support the proposed personnel qualifications documentation. Minimum qualification experience time is two (2) years.

A) Cooper control panel, CL-6B, 1-each.

US Embassy – Suva

3.2 ENGINEERING ASSESSMENT & OTHER SITE REQUIRED WORK. The contractor shall provide professional engineering services, assessments, inspections, and provide recommendations for any systems or equipment found to be defective, misapplied, incorrectly applied or installed, or otherwise deemed a safety, functionality or reliability hazard. For any equipment or systems determined to be in a failed or unusable state, the contractor shall perform a root cause failure analysis to determine the latent failure root and assess the equipment for repair/replacement requirements. As part of the commissioning and start up services, the contractor shall perform inspection, preventative maintenance, and system/equipment testing services for all medium voltage equipment. All work shall be completed in accordance with this statement of work, specific task/delivery order requirements and in accordance with manufacturer instructions, to verify and validate the electrical usability, integrity and continued functionality of the medium voltage system and assemblies. The contractor shall also perform all work utilizing Reliability Centered Maintenance techniques and process, including but not limited to predictive testing and inspection, infrared analysis, oil sampling and testing, vibration analysis, power and harmonic monitoring. The Contractor shall identify all National Electric Code (Based on NEC 2007) violations and provide remedies. During the course of this work the contractor should note any other known power problems at Post that is either witnessed or are that they are made aware of by embassy personnel.

3.3 COMMENCEMENT OF TRAVEL TO SITE AND WORK. All site visits and scope work must be completed no later than May 15, 2012. This includes subsequent paperwork and reporting. In conjunction with the work plan and price proposal provide a calendar of proposed visit dates, travel dates, and down days, along with the performing technician’s names and credentials. The listed site locations can be performed in any order. The same individuals do not have to perform the entire list of embassies as long as the work plan notes the change in team member, his/her credentials, and the separate flight info. OBO proposes that the contractor plan for a minimum three day site visit per post. The contractors work plan must indicate a full schedule and note the work days and travel days for each site. The contractor shall under no circumstances incur any travel or other costs, or begin the travel to the site or work at site until a signed purchase order is issued and a cable granting country clearance is received. Once all needed material is onsite, visit dates will be coordinated between embassy personnel, contract COR and the contractor. The contractor will be asked to furnish the COR the traveling technicians flight itinerary and security information.

3.4 SERVICE INTERRUPTIONS. The contractor shall plan, coordinate, and schedule all site work with the Facility Manager. Notification of this planned outage must be made to the Management Officer (Admin) and Information Management Officer. Notification shall include the loads within the facility to be affected by the outage and the hours and dates of interruptions. The contractor must schedule work to maintain flexibility since interruptions may not be granted on the date(s) requested. Electrical shutdowns and operation of electrical breakers, to include bypass transfer, shall be accomplished only by qualified personnel and upon advance approval of the Facility Manager. Where fire protection, detection, or evacuation alarms are affected, advance written approval of the Facility Manager shall be obtained. The implementation plan should be focused on minimizing any interruptions. Proper lock out/tag out procedures shall be followed to maximize safety; the contractor shall supply lock out/tag out materials. Power shall be maintained to all operational loads during normal working hours and maintained to all critical loads at all times except for planned and approved short duration switchovers or outages.

3.5 DEFECTIVE EQUIPMENT NOTED DURING INSPECTION. For any failed, unusable or inoperable equipment, the contractor shall perform an equipment failure investigation and root cause failure analysis to determine latent root failure causes. Identify and document the failure, resultant damages and provide information and data to avoid future failure occurrences. Include in the final report a recommended statement of work to repair/replace defective equipment components and/or replace the equipment in its entirety.

3.6 INSPECTION AND FAILURE ANALYSIS. All medium voltage equipment, systems and apparatus shall be inspected to confirm they are installed in a manner to protect and preserve the equipment from adverse physical and environmental effects. Ensure that the equipment is installed in accordance with customary/industry electrical practice, and to ensure the equipment is installed in accordance with applicable code requirements, and manufacturer recommendations. When the Contractor completes work on a system or piece of equipment included in this contract, that system or piece of equipment shall be free of missing components or defects which would prevent it from functioning as originally intended and/or designed. Corrective repair/replacement work shall be carried to completion, including operational checks and cleanup of work site. Except where noted otherwise, replacement components and systems shall match existing in dimensions, finish, color, and design. The contractor shall inspect and investigate the equipment to determine the root cause failure of the equipment and to determine the latent cause of the failure, including proper course of action needed to return the equipment to an operational state. All aspects of this investigation shall be documented via a root cause failure analysis and documented via a RFCA report with all technical recommendations/advisement provided by the contractor to the CO. Any recommendations for equipment replacement or upgrade shall include all technical data and justification to fully support replacement decisions by the USG. All contractor equipment replacement recommendations shall be conducted utilizing sound technical and engineering judgments based on best practice industry standards and taking into consideration Post operational requirements, and power conditions. The intent of this investigation is to ascertain the reasons why the equipment failed, and corrective actions needed to restore equipment service to ensure its sustained usability, functionality and reliability to provide a continued service level to Post operations. The contractor shall also assess and document the existing equipment as employed, calculate, measure and document equipment loading requirements including all loads applied and provide specific technical data relating to systems or equipment that the contractor recommends for replacement/installation. For the latter, the contractor shall take into consideration all requirements to ensure that any recommendations for replacement equipment/system can meet Post functional operations with sustained reliability and functionality.

3.7 SITE RESTORATION. The contractor shall ensure that all facilities receiving this work shall be left in a condition acceptable to the OBO Facility Manager, and the COR.

3.8 DISPOSAL OF MATERIALS REMOVED. The embassy shall be responsible for the disposal of all trash created while performing this work statement. The contractor shall transport all materials to be disposed of from the point of removal to the designated disposal storage site, and shall ensure that all items removed through this work are disposed of properly.

4.0 TRAINING. Provide training to one or more embassy representatives on unit operation and safety concerns. Provide training using the site specific SOPs to demonstrate proper AVR isolation and lock-out procedures required for any maintenance action on the AVR. Train on the SOP for control panel replacement. Emphasize that all AVR bypass switching, cleaning, and control panel replacements are to be performed with the AVR de-energized. Discuss during training other electrical safe work practices such as lock-out/tag-out of an ATS or Switchgear isolation. Training shall be given until the representatives have an adequate comfort level with the unit’s operation and maintenance SOPs, not to exceed 6 hours.

4.1 SAFETY. Safety is the highest priority on this and all OBO/CFSM/FM projects. The contractor shall direct all of those under his charge to work safely. Regular safety meetings shall be held among on-site contractor personnel, and safety concerns shall be brought to the attention of the Post Safety and Health Officer (POSHO) and the COR.

4.2 REQUIREMENTS AND DELIVERABLES. All site visits and scope work must be completed no later than May 15, 2012. This includes subsequent paperwork, and all final site visit reports. The contractor shall provide two (2) copies of a typed summary report PER POST. No group or compilation report will be accepted. The report must be written in the English language. The report can be either hard copy or delivered electronically. One report to be delivered to the post’s Facility Manager, and the other to James Alden, OBO/CFSM/FM/MS, Dept. of State, Washington, D.C., 20522-0601, or aldenjn@state.gov. Required deliverables are as follows:

1. Narrative summary site report to include all unit nameplates, conditions, findings, repairs or corrective measures, completed inspection and testing checklists per each site visit location. Provide a BOM showing part number and price for any recommended or required material not presently onsite. Executive summary must address all items in section 2 of the SOW. Provide SOP for voltage regulator lock-out isolation for each post. Note any follow up repair or future maintenance requirements/recommendations.

2. Provide photos of all applicable MV gear, inventory, and updated one-line as built print.

3. In the event of a failed regulator, contractor must provide a Root Cause Failure Analysis (RCFA) and latent failure roots, inspections and testing results, testing methods and results and all findings and recommendations for follow-on work to restore the AVR equipment to a fully functional and safe operating state.

4. Site personnel training on AVR operation, and MV safety as per SOW.

4.3 SECURITY REQUIREMENTS. None; The contractor will be escorted whenever necessary.

5.0 PROJECT COSTS AND TRAVEL. This section provides the basis for payment of the contractor, and defines those activities related to the project that will be paid directly by OBO and the Embassy.

5.1 BASIS. The agreed upon cost of this work shall be a fixed price inclusive of all labor, equipment, materials, shipping, travel, and per diem costs.

5.2 ALLOWANCE FOR MISCELLANEOUS TIME REQUIREMENTS. The contractor’s price proposal must allow for time delays that may be encountered in coordination of a planned AVR outage. Including but not limited to delayed access to certain building spaces, meetings and report writing. No additional funds will be provided to compensate for additional time requirements or delays that could have been reasonably anticipated.

5.3 TRAVEL AND PER DIEM. It is the contractor’s responsibility to understand Department of State travel rules and guidelines for contractors prior to incurring any costs. Costs incurred in violation of established travel rules and guidelines of the Department of State shall not be paid. If a visa is required for any location it is the contractor’s responsibility to have a valid passport and obtain a visa. Refer to Para. 3.3 of this work statement for further travel details.

5.4 PROJECT COMMENCEMENT. The contractor shall provide a travel schedule detailing number of days at each site, travel days between sites, and full itinerary routing as a work plan in conjunction with cost proposal.

** End SOW **

SOW – Medium Voltage AVR