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3yr. Electrical Inspection and Service - Attachment

General Information

Document Type:FILE
Posted Date:Sep 28, 2018
Category: Quality Control, Testing and Inspection Services
Set Aside:N/A

Contracting Office Address

Department of Veterans Affairs;Network Contracting Office (NCO) 15;3450 S 4th Street Trafficway;Leavenworth KS 66048

Description

DRAFT STATEMENT OF WORK PROFESSIONAL TESTING AND MAINTENANCE OF ELECTRICAL SYSTEMS AND EQUIPMENT 1. GENERAL: 1.1 The work under this contract shall be performed under supervision of a Registered Professional Engineer. The Registered Professional Engineer shall be on site initially to discuss with the Engineering Officer the procedures used to test, survey, report and service the equipment required to be serviced under this contract. The Registered Professional Engineer shall supervise the services personally, review the final report and discuss with the Engineering Officer the results of the services, any recommendations, future actions and professional opinions, which are contained in the report. 1.2 Field service work shall be performed directly by Field Service Engineers who have successfully demonstrated their knowledge and experience in the Field of Electrical Power Distribution Systems Testing. The Field Service Engineer shall be capable of the following: (1) testing, assessing, evaluating, servicing and reconditioning components, (2) assuring that the equipment on which work has been performed is safe, reliable and acceptable for its intended purpose, and (3) identifying defective equipment and potential safety problems, environmental hazards or code violations. 1.3 The Supervising Service Engineer must be accredited as a Certified Electrical Test Technologist by the NICET (National Institute for Certification of Engineering Technologists) or the NETA (National Electrical Testing Association) or similar certification and have a minimum of five (5) years of experience on similar major testing projects. 1.4 All other testing technicians assigned to the project must be certified by NICET, NETA, or must have an equivalent qualification certification. 1.5 Test assistants and apprentices may be assigned to the project as assistants to certified technicians at a ratio not to exceed two certified to one non-certified assistant or apprentice. 1.6 The names and certification numbers of the Registered Professional Engineer supervising the work and signing the test reports and the Supervising Field Service Engineer must be provided by the Contractor and verified by the Contracting Officer before contract award. After contract award, similar data for all certified technicians who will be assigned to work on the project must also be submitted and approved before starting work on the contract. 1.7 All work performed shall be fully documented by the Contractor. Testing shall be performed in compliance with manufacturers recommendations and applicable NEMA, NETA, ANSI, ASTM, ASA and VA Standards and as specified for each section in specifications. 1.8 All outages shall be scheduled and approved in writing at least two weeks in advance. Outages will be scheduled only at night and on weekends. 2. SCOPE 2.1 THREE YEAR ELECTRICAL SYSTEM MAINTENANCE AND TESTING. 2.2 Switchgear equipment. Medium Voltage Circuit Breakers and Protective Relays. 2.2.1 Record switchgear, breaker and device nameplate information and compare with the facilitys one-line diagram, when available. Identify and record discrepancies. 2.2.2 Inspect all electrical equipment, including each breaker, and report damage or malfunctioning equipment, loose connections or material or any contamination that must be corrected. Clean where appropriate. 2.2.3 Check equipment for level, security to foundation and operation of doors. Report any unfavorable environmental conditions such as excessive moisture or conducting dust that must be corrected. Clean where appropriate. 2.2.4 Visually inspect the equipment ground and record the number and size of ground bus and straps. Report deficiencies. 2.2.5 Inspect the insulation system on the primary bus and assemblies. Test insulation on each bus, phase-to-phase and phase-to-ground with suitable megohmmeter. Record values, report deficiencies, and clean where appropriate. 2.2.6 Draw or rack each breaker from its cell. Remove arc chutes, clean, inspect and adjust all contacts as necessary. Measure and record contact resistance in micro-ohms and clean all insulating surfaces. Megger and record phase-to-phase and phase-to-ground. Lubricate as necessary. 2.2.7 Electrically close and trip each breaker with control switch. Manually close and trip each breaker. Trip each breaker with each of its protective devices. Tighten all connections. Record any discrepancies. 2.2.8 Remove each relay from its case. Clean, inspect and tighten all connections. Apply three multiples of relay tap current to each relay to verify manufacturers time current characteristics. Test each relay for instantaneous pickup. Report deficiencies and adjust where appropriate. 2.3 Primary Disconnects. 2.3.1 De-energize entire substation clean all insulating surface and clean and dress all contacts. 2.3.2 Activate each switch. Insure switch completely disengages and closes clean switch and lubricate as required. 2.3.3 Measure contact resistance in micro-ohms, Megger each phase-to-ground. Record any discrepancies. 2.3.4 Clean and inspect cubicle, tighten all untapped connections, and lubricate as necessary. 2.4 Transformers 2.4.1 Record transformer nameplate information and compare with the facilitys one-line diagram, when available. Record discrepancies. 2.4.2 Inspect transformer and accessories and report damage, loose connections or material, shipping blocks, or contamination that must be corrected. Clean where appropriate. Inspect for leaks and tighten all untaped connections. Clean all insulating surfaces. 2.5 Low Volta= Circuit Breakers 2.5.1 Record switchgear, breaker and device nameplate information and compare with the facilitys one line diagram, when available. Record discrepancies 2.5.2 Inspect equipment and each breaker and report damage, loose connections or material, or contamination that must be corrected. Clean where appropriate. 2.5.3 Check equipment for level, security to foundation, and operation of doors. Report any unfavorable environmental conditions such as excessive moisture or conducting dust that must be corrected. Clean where appropriate. 2.5.4 Visually inspect the equipment ground and record the number and size of ground bus and straps. Report deficiencies. 2.5.5 Inspect the insulation system on the primary bus and assemblies. Test insulation on each bus, phase-to-phase and phase-to-ground with suitable megohmmeter. Record values, report deficiencies and clean where appropriate. 2.5.6 Clean and inspect each breaker. Megger phase-to-phase and phase-to-ground and measure contact resistance in micro-ohms. Test each series over-current trip device for pickup at 200% and 300 of its rating and for instantaneous pickup. Clean and dress all contact surfaces and lubricate as necessary. 2. 6 Generators 2.6.1 Record nameplate data including manufacturer, age and capacity. List fuel type, KM load under load condition, number of hours of fuel tank capacity and number of hours of accumulated run time. 3. TEST EQUIPMENT 3.1 Suitability of Test Equipment 3.1.1 All test equipment shall be in good mechanical and electrical condition. 3.1.2 Split-core current transformers and clamp-on or tong type ammeters require careful consideration of the following in regard to accuracy: 3.1.2.1 Position of the conductor within the core. 3.1.2.2 Clean, tight fit of the core pole faces. 3.1.2.3 Presence of external fields. 3.1.2.4 Accuracy of the current transformer ratio in addition to the accuracy of the secondary meter. 3.1.3 Selection of metering equipment should be based on a knowledge of the waveform of the variable being measured. Modern digital multimeters may be average or rms. sensing and may include or exclude the do component. When the variable contains harmonics or do offset and in general, any deviation from a pure sine wave, average sensing, rms. scaled meters may be misleading. 3.1.4 Field test metering used to check power system meter calibration must have an accuracy higher than that of the instrument being checked. 3.1.5 Accuracy of metering in test equipment shall be appropriate for the test being performed but not in excess of 2% of the scale used. 3.1.6 Waveshape and frequency of test equipment output waveforms shall be appropriate for the test and tested equipment. 3.2 Test Instrument Calibration 3.2.1 The testing firm shall have a calibration program which assures that all applicable test instruments are maintained within rated accuracy. 3.2.2 The accuracy shall be directly traceable to the National Institute of Standards and Technology. 3.2.3 Instruments shall be calibrated in accordance with the following frequency schedule: 3.2.3.1 Field instruments: Analog-6 months maximum: Digital-12 months maximum. 3.2.3.2 Laboratory instruments: 12 months. 3.2.3.3 Leased specialty equipment: 12 months (Where accuracy is guaranteed by lessor). 3.2.4 Dated calibration labels shall be visible on all test equipment. - 3.2.5 Records, which show date and results of instruments calibrated or tested, must be kept up-to-date. 3.2.6 Up-to-date instrument calibration instructions and procedures shall be maintained for each test instrument. 3.2.7 Calibrating standard shall be of higher accuracy than that of the instrument tested. 3.3 Test Resort 3.3.1 The test report shall include the following: 3.3.1.1 Summary of project. 3.3.1.2 Description of equipment tested. 3.3.1.3 Description of test. 3.3.1.4 Test results. 3.3.2 Furnish a copy or copies of the complete report to the owner/users representative as directed in the maintenance contract. 4. INSPECTION AND TEST PROCEDURES 4.1 Switchgear and Switchboard Assemblies 4.1.1 Visual and Mechanical Inspection 4.1.1.1 Inspect for physical, electrical and mechanical condition. 4.1.1.2 Compare equipment nameplate information with latest one line diagram when available and report discrepancies. 4.1.1.3 Check for proper anchorage, required area clearances, physical damage, and proper alignment. 4.1.1.4 Inspect all bus connections for high resistance. Use low resistance ohmmeter, or check tightness of bolted bus joints by calibrated torque wrench method. In lieu of above tonguing, perform infrared survey in accordance with Section 9. 4.1.1.5 Test all electrical and mechanical interlock systems for proper operation and sequencing. 4.1.1.5.1 Closure attempt shall be made on locked open devices. Opening attempt shall be made on locked closed devices. 4.1.1.5.2 Key exchange shall be made with devices operated in off-normal positions. 4.1.1.6 Clean switchgear. 4.1.1.7 Inspect accessible insulators for evidence of physical damage or contaminated surfaces. 4.1.1.8 Verify proper barrier and shutter installation and operation. 4.1.1.9 Lubrication. 4.1.1.9.1 Verify appropriate contact lubricant on moving current carrying parts. 4.1.1.9.2 Verify appropriate lubrication on moving and sliding surfaces. 4.1.1.10 Exercise all active components. 4.1.1.11 Inspect all mechanical indicating devices for proper operation. 4.1.2 Electrical Tests 4.1.2.1 Perform ground resistance tests in accordance with Section 4.8. 4.1.2.2 Perform insulation resistance tests on each bus section, phase-to-phase and phase-to-ground for one (1) minute. Test voltages shall be in accordance with Table 4.1.1. 4.1.2.3 Perform control wiring performance test. Use the elementary diagrams of the switchgear to identify each remote control and protective device. Conduct tests to verify satisfactory performance of each control feature. 4.1.2.4 Perform overpotential tests on each bus section, phase-to-phase and phase-to-ground. Test voltages shall be in accordance with Table 4.1.2. 4.1.2.5 Control Power Transformer - Dry Type 4.1.2.5.1 Inspect for physical damage, cracked insulation, broken leads, tightness of connections, defective wiring, and overall general condition. 4.1.2.5.2 Verify that primary and secondary fuse ratings or circuit breakers match drawings. 4.1.2.5.3 Perform insulation resistance test. Measurements shall be made from winding-to-winding and windings-to-ground. Test voltages and minimum resistances shall be in accordance with Table 4.2.1. Results to be temperature corrected in accordance with Table 4.2.2. 4.1.3 Test values 4.1.3.1 Bolt torque levels shall be in accordance with Table 8.1, unless otherwise specified by manufacturer. 4.1.3.2 Insulation resistance test shall be performed in accordance with Table 4.1.1. Values of insulation resistance less than his table or manufacturers minimum should be investigated. 4.1.3.3 Overpotential test voltages shall be applied in accordance with Table 4.1.2-(Derived from ANSI/IEEE C37.20.2). Test results are evaluated on a go, no-go basis by slowly raising the test voltage to the required value. The final test voltage shall be applied for one (1) minutes. TABLE 4.1.1 Switchgear Insulation Resistance Test Voltage Voltage Rating Minimum dc Test Voltage Recommended Minimum Insulation Resistance In Megohms 0-250V 500V 50 251-600V 1000V 100 601-5000V 2500V 1000 5001-15000V 2500V 5000 15001-25000V 5000V 20000 TABLE 4.1.2 Field Overpotential Test Voltages* Maximum Type of Switchgear Rated TV Test Voltage kV ac de MC 4.76 14.3 20.3 (Metal Clad 8.25 27.0 37.5 Switchgear) 15.0 27.0 37.5 38.0 60.0 SC 15.5 37.5 + (Station-type Cubicle 38.0 60.0 + Switchgear) 72.5 120.0 + MEI 4.76 14.3 20.3 (Metal-Enclosed 8.25 19.5 27.8 Interrupter 15.0 27.0 37.5 Switchgear) 15.5 37.5 52.5 25.8 45.0 38.0 60.0 +Consult Manufacturer Derived from ANSI/IEEE 037.20.2, Paragraph 5.5 and C37.20.3, paragraph 5.5 4.2 Transformers 4.2.1 Transformers-Dry Type 4.2.1.1 Visual and Mechanical Inspection 4.2.1.1.1 Inspect for physical damage, cracked insulators, lightness of connections, defective wiring and general mechanical and electrical conditions. 4.2.1.1.2 Verify proper auxiliary device operation such as fans and indicators. 4.2.1.1.3 Check tightness of accessible bolted electrical joints in accordance with Table 7.1. 4.2.1.1.4 Perform specific inspections and mechanical tests as recommended by manufacturer. 4.2.1.1.5 Make a close examination for shipping brackets or fixtures that may not have been removed during original installation. Ensure resilient mounts are free. 4.2.1.1.6 Verify proper core grounding. 4.2.1.1.7 Verify proper equipment grounding. 4.2.1.1.8 Thoroughly clean unit prior to testing unless "as found" and "as left" tests are required. 4.2.1.2 Electrical Tests 4.2.1.2.1 Perform insulation resistance tests, winding to-winding and windings-to-ground, utilizing a megohmmeter with test voltage output as shown in Table 4.2.3. 4.2.2.1 Visual and Mechanical Inspection. 4.2.1.2.1.1 Test duration shall be for 10 minutes with resistances tabulated at 30 seconds, 1 minute, and 10 minutes. Dielectric absorption ratio and polarization index will be calculated. 4.2.1.2.1.2 Perform tests and adjustments for fans, controls, and alarm functions. 4.2.1.2.1.3 Verify that tap-changer is set at specified ratio. 4.2.1.2.1.4 Verify proper secondary voltage phase-to-phase and phase-to-neutral after energization and prior to loading. 4.2.1.3 Test Values 4.2.1.3.1 Insulation resistance test values should not be less than values recommended in Table 4.2.3 Results shall be temperature corrected in accordance with Table 4.2.4. 4.2.1.3.2 The polarization index should be above 1.2 unless an extremely high value is obtained initially, which when doubled will not yield a meaningful value. 4.2.1.3.3 Turns ratio test results should not deviate more than one-half of the percent (0.5%) from either the adjacent coils or the calculated ratio. 4.2.1.3.4 CH and-CL power factor values will vary due to support insulators and bus work utilized on dry transformers. The following should be expected on CHL power factors. Power Transformers: 3% or less Distribution Transformers: 5% or less 4.2.1.3.5 Winding resistance test results should compare within one percent (1%) of adjacent windings. 4.2.1.3.6 Excitation current test data pattern: Two similar current readings for outside coils and a dissimilar current reading for the center coil of a three phase unit. 4.2.2 Transformers - Liquid Filled 4.2.2.1 Visual and Mechanical Inspection 4.2.2.1.1 Inspect for physical damage, cracked insulators, leaks, tightness of connections, and general mechanical and electrical conditions. 4.2.2.1.2 Verify proper auxiliary device operation. 4.2.2.1.3 Check tightness of accessible bolted electrical connections in accordance with Table 7.1. 4.2.2.1.4 Verify proper liquid level in all tanks and bushings. 4.2.2.1.5 Perform specific inspections and mechanical tests as recommended by manufacturer. 4.2.2.1.6 Verify proper equipment grounding. 4.2.2.2 Electrical Tests 4.2.2.2.1 Perform insulation resistance tests, winding to-winding and windings-to-ground, utilizing a megohmmeter with test voltage output as shown in Table 4.2.3. 4.2.2.2.1.1 Test duration shall be for 10 minutes with resistances tabulated at 30 seconds, 1 minute, and 10 minutes. Calculate dielectric absorption ratio and polarization index. 4.2.2.2.2 Perform a turns ratio test between windings at designated tap position. The tap setting is to be determined by the owner/users electrical engineer and set by the testing laboratory. 4.2.2.2.3 Perform insulation power factor tests or dissipation factor tests on all windings and bushings. Overall dielectric-loss and power factor (CHI, CL, TEL) shall be determined. Test voltages should be limited to the line to ground voltage rating of the transformer winding. 4.2.3 Test Values 4.2.3.1 Insulation resistance and absorption test. Test voltages to be in accordance with Table 4.2.3. Resistance values to be temperature corrected in accordance with Table 4.2.4. 4.2.3.2 The polarization index should be above 1.2 unless an extremely high value is obtained initially, which when doubled will not yield a meaningful value. 4.2.3.3 Tummy ratio test results shall not deviate more than one half percent (0.5%) from either the adjacent coils or the calculated ratio. 4.2.3.4 Maximum power factor of liquid filled transformers corrected to 20 degrees C shall be in accordance with Table 4.2.1. TABLE 4.2.1 Oil silicone Tetrachlor High Fire ethylene Point Hydro carbon Power Transformers 0.5% 0.5% 3.0% 0.5% Distribution Transformers 1.0% 0.5% 3.0% 1.0% 4.2.3.5 Bushing power factors and capacitances that vary from nameplate values by more than ten percent (10%) should be investigated. 4.2.3.6 Excitation current test data pattern: Two similar current readings for outside coils and a dissimilar current reading for the center coil of a three phase unit. 4.2.3.7 Dielectric fluid should comply with Table 4.2.2. 4.2.3.8 Winding resistance test results should compare within one percent (1%) of adjacent windings. TABLE 4.12 High Molecular Tetrchlor Oil Weight Silicone ethylene Hydrocarbon Dielectric Breakdown 24 kV 30 kV 30 kV 30 kV ASTM D-877 Minimum Minimum Minimum Minimum Dielectric Breakdown ASTM D-1816 @0.04" gap 34.5 kV and below 20 kV 26 kV Minimum Minimum above 34.5 kV 25 kV Neutralization 0.36 mgKOH/g 0.03 mgKOH/g.01 mgKOH/g.25 mgKOH/g #ASTM D-974 Maximum Maximum Maximum Maximum Interfacial 21 dynes/cm 33 dynes/cm Tension ASTM D-974 Minimum Minimum or D-2285 Color 3.0 3.0 N/A 0.05 ASTM Maximum Maximum D-1500 (D-2129) Visual Condition Compare to N/A Crystal Clear, Slight ASTM Previous Clear Pink Irre D-1524 Tests descent Power Factor 1.0% 0.1% 0.1% 2% ASTM D-924 Maximum Maximum Maximum Maximum Q25 degrees Water Con tent ASTM D-1533 35 PPM* 35 PPM 80 PPM25 PPM 15 kV & Maximum Maximum Maximum Maximum below above 15 kV-below 25 PPM* 115 kV Maximum 115 kV- 20 PPM* 230 kV Maximum above 15 PPM 230 kV Maximum *Or in accordance with manufacturers requirements. Some manufacturers recommend 15 PAM maximum for all transformers. Note: The values for oil are taken from ANSI C57.106 (IEEE Std. 64). The remaining values are acceptance test values and should be modified for service aged fluid as recommended by the manufacturer. 4.2.4 Small Transformers - Dry Type, Air Cooled (600 Volt and Below) (less than 100 kVA single-phase or 300 kVA three phase). 4.2.4.1 Inspect for physical damage, broken insulation, tightness of connections, defective wiring, and general condition. 4.2.4.2 Thoroughly clean unit prior to making any tests. 4.2.4.3 Perform insulation resistance test. Calculate dielectric absorption ratio and polarization index. Measurements shall be made from winding-to-winding and windings-to-ground. Test voltages and minimum resistance shall be in accordance with Table 4.2.3. Results to be temperature corrected in accordance with Table 4.2.4. TABLE 4.2.3 Transformer Insulation Resistance Test Voltage Recommended Minimum Minimum Insulation Transformer Coil de Resistance in Megohms Rating Type Test Voltage Liquid Filled Dry 0 - 600 Volts 1000 Volts 100 500 601 - 5000 Volts 2500 Volts 1000 5000 5001 - 15000 Volts 5000 Volts 5000 25000 TABLE 4.2.4 C Transformer Insulation Resistance Temperature Correction Factors to 20 degrees C TEMPERATURE F OIL TRANSFORMER DRY 0 32.25.40 5 41.36.45 10 50.50.50 15 59.75.75 20 68 1.00 1.00 25 77 1.40 1.30 30 86 1.98 1.60 35 95 2.80 2.05 40 104 3.95 2.50 45 113 5.60 3.25 50 122 7.85 4.00 55 131 11.20 5.20 60 140 15.85 6.40 65 149 22.40 8.70 70 158 31.75 10.00 75 167 44.70 13.00 80 176 63.50 16.00 4.3 Cables 4.3.1 Cables - Low Voltage - 600V Maximum 4.3.1.1 Visual and Mechanical Inspection 4.3.1.1.1 Inspect exposed sections of cables for physical damage. 4.3.1.1.2 Test cable mechanical connections to manufacturers recommended values with a calibrated torque wrench. In lieu of above torquing, perform infrared survey in accordance with Section 6. 4.3.1.2 Electrical Tests 4.3.1.2.1 Perform insulation resistance test on each conductor with respect to ground and adjacent conductors. Applied potential to be 1000 volts do for 1 minute. 4.3.1.3 Test Values 4.3.1.3.1 Minimum insulation resistance values shall be not less than two megohms. 4.3.2 Cables - Medium Voltage - 69 kV Maximum 4.3.2.1 Visual and Mechanical Inspection 4.3.2.1.1 Inspect exposed sections for physical damage. 4.3.2.1.2 Inspect for shield grounding, cable support and termination. 4.3.2.1.3 Inspect fireproofing in common cable areas. 4.3.2.1.4 If cables are terminated through window type CTs, make an inspection to verify that neutrals and grounds are properly terminated for proper operation of protective devices. 4.3.2.2 Electrical Tests 4.3.2.2.1 Perform a shield continuity test on each power cable. Ohmic value hall be recorded. 4.3.2.2.2 Perform a do high potential test on all cables. Adhere to all precautions and limits as specified in the applicable NEMA/ICEA Standard for the specific cable. Perform tests in accordance with ANSI/IEEE Std. 400. Test procedure shall be as follows, and the results for each cable test shall be recorded as specified herein. Test voltages shall not exceed 60% of cable manufacturers factory test value or the maximum test voltage in table 4.3.1. 4.3.2.2.2.1 Current sensing circuits in test equipment shall measure only the leakage current associated with the cable under test and shall not include internal leakage of the test equipment. 4.3.2.2.2.2 Record wet and dry bulb temperatures of relative humidify end temperature. 4.3.2.2.2.3 Test each section of cable individually. 4.3.2.2.2.4 Individually test each conductor with all other conductors grounded. Ground all shields. 4.3.2.2.2.5 Terminations shall be, property corona suppressed by guard ring, field reduction sphere, or other suitable methods. 4.3.2.2.2.6 Ensure that the maximum test voltage does not exceed the limits for terminators specified in IEEE Standard 48 or manufacturers specifications. 4.3.2.2.2.7 Apply a do high potential test in at least five equal increment shall exceed the voltage rating of the cable. Record do leakage current at each step after a constant stabilization time consistent with system changing current. 4.3.2.2.2.8 Raise the conductor to the Specified maximum test voltage and hold for a minimum of five minutes. Record readings of leakage current at 30 seconds and one minute and at one minute intervals thereafter. 4.3.2.2.2.9 Reduce the conductor test potential to zero and measure residual voltage at discrete intervals. 4.3.2.2.2.10 Apply grounds for a time period adequate to drain all insulation stored charge. Proper notification must be made to all concerned parties if grounds are left in place. TABLE 4.3.1 Maximum Maintenance Test Voltages (kV,dc) 1968 and Later Cable Rated Insulation Cable Test Voltage Insulation Type Level Voltage kV.dc Elastomeric: Butyl and 100% 5kV 19 Oil Base 100% 15kV 41 100% 25kV 60 133% 5kV 19 133% 15kV 49 Elastomeric: EPR 100% kV 19 100% 5kV 41 100% 25kV 60 100% 35kV 75 133% 5kV 19 133% 15kV 49 133% 25kV 75 Polyethylene 100% 5kV 19 100% 15kV 41 100% 25kV 60 100% 35kV 75 133% 5kV 19 133% 15kV 49 133% 25kV 75 Derived from ANSI/IEEE std. 141-1986 Table 82 Note: Selection of test voltage for in-service cables depends on many factors. The owner should be consulted and/or informed of the intended test voltage prior to performing the test. The above tables are consistent with ILEA recommendations. AE1C C55 and C56, and ANSI/WEE Std. 400 specify higher voltages. It the cable fails during the test it will require repair or replacement prior to re-energizing. 4.3.2.3 Test Values 4.3.2.3.1 Shielding must exhibit continuity. Investigate resistance values in excess of 10 ohms per 1000 feet of cable. *4.3.2.3.2 A graphic plot may be made with leakage current (X axis) versus voltage (Y axis) at each increment. 4.3.2.3.2.1 The step voltage slope should be reasonably linear. 4.3.2.3.2.2 Absorption slope should be flat or negative. In no case should slope exhibit a positive characteristic. 4.3.2.3.2.3 compare test results to previously obtained results. 4.4 Metal Enclosed Busways 4.4.1 Visual and Mechanical Inspection 4.4.1.1 Inspect bus for physical damage. 4.4.1.2 Inspect for proper bracing, suspension alignment, and enclosure ground. 4.4.1.3 Check tightness of bolted joints by calibrated torque wrench method in accordance with manufacturers published data or Table 7.1 In lieu of above torquing perform infrared survey in accordance with Section 6. 4.4.1.4 Check outdoor busway for removal of "weephole" plugs, if applicable, and the proper installation of joint shield. 4.4.2 Electrical Tests 4.4.2.1 Measure insulation resistance of each bus run phase-to-ground for one (1) minute. 4.4.3 Test Values 4.4.3.1 Bus bolt torque values shall be in accordance with manufacturers recommendations or Table 8.1. 4.4.3.2 Insulation resistance test voltages and resistance values shall be in accordance with manufacturers specifications or Table 7.2. 4.5 Air Switches - Medium Voltage - Metal Enclosed 4.5.1 Visual and Mechanical Inspection 4.5.1.1 Inspect for physical and mechanical condition. 4.5.1.2 Check for proper anchorage and required area clearances. 4.5.1.3 Verify that fuse sizes and types correspond to drawings. 4.5.1.4 Perform mechanical operator tests in accordance with manufacturers instructions. 4.5.1.5 Check blade alignment and arc interrupter operation. 4.5.1.6 Verify that expulsion limiting devices are in place on all holders having expulsion type elements. 4.5.1.7 Check each fuse holder for adequate mechanical support for each fuse. 4.5.1.8 Inspect all bus connections for tightness of bolted bus joints by calibrated torque wrench method. Refer to manufacturers instructions or Table 8.1 for proper torque levels. In lieu of above torque tests, perform infrared survey in accordance with Section 6. 4.5.1.9 Test all electrical and mechanical interlock systems for proper operation and sequencing. 4.5.1.10 Clean entire switch using approved methods and materials. 4.5.1.11 Verify proper phase barrier materials and installation. 4.5.1.12 Lubricate as required. 4.5.1.13 Check switch blade clearances with manufacturers published data. 4.5.1.14 Inspect all indicating devices for proper operation. 4.5.2 Electrical Tests 4.5.2.1 Perform insulation resistance tests on each pole, phase-to-phase and phase-to-ground for one (1) minute. Test voltage and minimum resistances should be in accordance with Table 8.2. In lieu of this test, perform appropriate insulation tests in conjunction with medium voltage cable insulation tests and/or power transformer primary winding tests. 4.5.2.2 Perform contact resistance test across each switch blade and fuse holder. 4.5.3 Test Values 4.5.3.1 Bolt torque levels shall be in accordance with Table 8.1 unless otherwise specified by manufacturer. 4.5.3.2 Perform insulation resistance test in accordance with Table 4.1.1. Investigate values of insulation resistance less than this table or manufacturers minimum. 4.5.3.3 Determine contact resistance in microhms. Investigate any value exceeding 100 microhms or any values which deviate from adjacent poles or similar switches by more than fifty percent (50%). 4.5.4 Air Switches-High and Medium Voltage-Open 4.5.4.1 Visual and Mechanical Inspection 4.5.4.1.1 Inspect for physical damage and compare nameplate data with plans and specifications. 4.5.4.1.2 Perform mechanical operator tests in accordance with manufacturers instructions. 4.5.4.1.3 Check blade alignment and arc interrupter operation. 4.5.4.1.4 Check fuse link or element and holder for proper current rating. 4.5.4.2 Electrical Tests 4.5.4.2.1 Perform ac or do overpotential test on each pole-to-ground and pole-to-pole. 4.5.4.2.2 Perform contact resistance teat across each switch blade. 4.5.4.3 Test Values 4.5.4.3.1 Apply overpotential test voltages in accordance with Table 4.1.6. 4.5.4.3.2 Contact resistance shall be determined in microhms. Investigate any value exceeding 500 microhms or any values which deviate from adjacent poles or similar switches by more than fifty percent (50%). 4.6 Circuit Breakers 4.6.1 Circuit Breakers-Low Voltage 4.6.1.1 Circuit Breakers-Low Voltage-Insulated Case 4.6.1.1.1 Visual and Mechanical Inspection 4.6.1.1.1.1 Check circuit breaker for proper mounting. 4.6.1.1.1.2 Operate circuit breaker to ensure smooth operation. 4.6.1.1.1.3 Inspect case for cracks or other defects. 4.6.1.1.1.4 Check tightness of connections with calibrated torque wrench. Refer to manufacturers instructions or Table 8.1 for proper torque levels. In lieu of this test, perform infrared survey in accordance with Section 6. 4.6.1.1.1.5 Check internals on unsealed units. 4.6.1.1.2 Electrical Tests 4.6.1.1.2.1 Perform a contact resistance test. 4.6.1.1.2.2 Perform an insulation resistance test at 1000 volts do from pole to-pole and from each pole-to ground with breaker closed and across open contacts of each phase. 4.6.1.1.2.3 Perform long time delay time current characteristic tests by passing three hundred percent (300%) rated current through each pole separately. Record trip time. Make external adjustments as required to meet time current curves. 4.6.1.1.2.4 Determine short time pickup and delay by primary current injection. 4.6.1.1.2.5 Determine ground fault pickup and time delay by primary current injection. 4.6.1.1.2.6 Determine instantaneous pickup current by primary injection using run-up or pulse method. 4.6.1.1.2.7 Perform adjustments for final settings in accordance with breaker setting sheet when applicable. 4.6.1.1.3 Test Values 4.6.1.1.3.1 Compare contact resistance or millivolt drop values to adjacent poles and similar breakers. Investigate deviations of more than fifty (50%). Investigate any value exceeding manufacturers recommendations. 4.6.1.1.3.2 Insulation resistance shall not be less than 100 megohms. Investigate values less than 100 megohms. 4.6.1.1.3.3 Trip characteristic of breakers shall fall within manufacturers published time-current characteristic tolerance band, including adjustment factors. 4.6.1.1.3.4 All trip times shall fall within Table 4.6.1.1. Circuit breaker" exceeding specified trip time at three hundred percent (300%) of pickup shall be tagged defective. 4.6.1.1.3.5 Instantaneous pickup values shall be within values shown on Table 4.6.1.2. TABLE 4.6. 1.1 Values for Overcurrent Trip Test (At 300% of Rated Continuous Current of Circuit Breaker) Breaker Voltage Volta Range of Related Continuous Current Amperes Maximum Trip Time in seconds* 240 15-45 50 240 50-100 70 600 15-45 70 600 50-100 125 240 110-225 200 240 250-400 300 600 110-225 250 600 50_400 300 600 450-600 350 600 700-1200 500 600 1400-2500 600 600 3000-5000 650 *For integrally-fused circuit breakers, trip times may be substantially longer if tested with the fuses replaced by solid links (shorting bars). TABLE 4.6.1.2 Instantaneous Trip Setting Tolerances Tolerances of High and Low Settings Frame Size, Amperes High Low <250 FIELD +40% +40% -25% -30% 400 FIELD +25% +30% 4.7 Circuit Breakers-Medium Voltage 4.7.1 Circuit Breakers-Medium Voltage-Air 4.7.1.1 Visual and Mechanical Inspection 4.7.1.1.1 Inspect for physical damage, cleanliness, and adequate lubrication. 4.7.1.1.2 Inspect anchorage, alignment, and grounding. 4.7.1.1.3 Perform all mechanical operator and contact alignment tests on both the breaker and its operating mechanism. 4.7.1.1.4 Check -tightness of bolted bus joints by calibrated torque wrench method. Refer to manufacturers instructions or Table 8.1 for proper torque levels. 4.7.1.1.5 Check cell fit and element alignment. 4.7.1.1.6 Check racking mechanism. 4.7.1.1.7 Verify that primary and secondary contact wipe and other dimensions vital to satisfactory operation of the breaker are correct. 4.7.1.1.8 Ensure that all maintenance devices are available for servicing and operating the breaker. 4.7.1.1.9 Lubricate all moving current carrying parts. 4.7.1.1.10 Check for proper operation of the cubicle shutter. 4.7.1.2 Electrical Tests 4.7.1.2.1 Measure contact resistance. 4.7.1.2.2 Measure insulation resistance pole-to-pole, pole-to-wound, and across open poles. Use a minimum test voltage of 2500 volts. *4.7.1.2.3 Perform insulation resistance test at 1000 volt. do on all control wiring. (Do not perform the test on wiring connected to solid state components). 4.7.1.2.4 With breaker in the test position, make the following tests: 4.7.1.2.4.1 Trip and close breaker with the control switch. 4.7.1.2.4.2 Trip each breaker by operating manually each of its protective relays. 4.7.1.3 Test Values 4.7.1.3.1 Determine contact resistance in microhms. Investigate deviations of more than 50%. 4.7.1.3.2 Minimum insulation resistance should comply with Table 4.1.1. 4.7.1.3.3 Power factor and arc chute watts lost should be compared with results from previous tests of similar breakers, or referred to manufacturers published data. 4.7.2 Circuit Breakers-Medium Voltage-Oil 4.7.2.1 Visual and Mechanical Inspection 4.7.2.1.1 Inspect for physical damage. 4.7.2.1.2 Inspect anchorage, alignment, and grounding. 4.7.2.1.3 Perform all mechanical operation and contact alignment tests on both the circuit breaker and its operating mechanism. 4.8 Metering and Instrumentation 4.8.1 Visual and Mechanical Inspection 4.8.1.1 Examine all devices for broken parts and wire connection tightness. 4.8.2 Electrical Tests 4.8.2.1 Check calibration of meters at all cardinal points. 4.8.2.2 Calibrate watt hour meters to one half of one percent (0.5%). 4.8.2.3 Verify all instrument multiplier-. 4.9 Grounding Systems 4.9.1 Visual and Mechanical Inspection 4.9.1.1 Inspect ground system for compliance with drawings. 4.9.2 Electrical Tests 4.9.2.1 Perform three (3) point fall-of-potential test per IEEE Standard No. 81, Section 9.04 on the main grounding electrode or system. 4.9.2.2 Perform the two (2) point method test per IEEE No. 81, Section 9.03 to determine the ground resistance between the main grounding system and all major electrical equipment frames, system neutral, and/or derived neutral points. 4.9.2.3 Alternate Method to 4.8.2.2: Perform ground continuity test between main ground system and equipment frame, system neutral, and/or derived neutral point. This test shall be made by passing a minimum of one (1) ampere do current between ground reference system and the ground point to be tested. Voltage drop shall be measured and resistance calculated by voltage drop method. 4.9.3 Test Values 4.9.3.1 The main ground electrode system resistance to ground should be no greater than five (5) ohms for commercial or industrial systems and one (1) ohm or 1QB for generating or transmission station grounds unless otherwise specified by the owner/users electrical engineer. 4.10 Direct Current Systems 4.10.1 Batteries 4.10.1.1 Visual and Mechanical Inspection 4.10.1.1.1 Inspect for physical damage and evidence of corrosion. 4.10.1.1.2 Check intercell bus link integrity. 4.10.1.2 Electrical Tests - Refer to ANSI/IEEE Standard 450 (lead) or ANSI/IEEE Standard 1106 (Nickel-Cadmium). 4.10.1.2.1 Measure bank charging voltage and each individual cell voltage. 4.10.1.2.2 Measure electrolyte specific gravity and visually check fill level. 4.10.1.2.3 Perform contact integrity tests across all connections between adjacent terminals. 4.10.1.2.4 Perform an integrity load test. 4.10.1.2.5 Perform a capacity load test at five year intervals. 4.10.1.2.6 Verify proper changing rates from charger during recharge mode. 4.10.1.2.7 Verify individual cell acceptance of charge during recharge mode. 4.11 Emergency Systems 4.11.1 Engine Generator-(Prime Mover is not addressed in this Specification). 4.11.1.1 Visual and Mechanical Inspection 4.11.1.1.1 Inspect for physical damage. 4.11.1.1.2 Inspect for proper anchorage and grounding. 4.11.1.2 Electrical and Mechanical Tests 4.11.1.2.1 Perform a dielectric absorption test on generator winding with respect to ground. Determine polarization index. 4.11.1.2.2 Test protective relay devices in accordance with applicable sections of these specifications. 4.11.1.2.3 Functionally tests engine shutdown for low oil pressure, overtemperature, over speed, and other features as applicable. 4.11.1.3 Test Values 4.11.1.3.1 Perform dielectric absorption at test voltage listed in Table 10.2. Polarization index values shall be in accordance with IEEE Standard 43. 4.11.2 Automatic Transfer Switches 4.11.2.1 Visual and Mechanical Inspection 4.11.2.1.1 Inspect for physical damage. 4.11.2.1.2 Check switch to ensure positive interlock between normal and alternate sources. Mechanical and Electrical. 4.11.2.1.3 Check tightness of all control and power connections. 4.11.2.1.4 Perform manual transfer operation with no connected load. 4.11.2.1.5 Ensure manual transfer warnings are attached and visible to operator. 4.11.2.2 Electrical Tests 4.11.2.2.1 Perform insulation resistance tests phase to-ground with switch in both source positions, where possible. 4.11.2.2.2 Perform a contact resistance test or measure millivolt drop across all main contacts. 4.11.2.2.3 Verify settings and operation of control devices in accordance with the owner/users electrical engineers specifications. 4.11.2.2.3.1 Voltage and frequency sensing relays. 4.11.2.2.3.2 All time delay relays. 4.11.2.2.3.3 Engine start and shutdown relays. 4.11.2.2.4 Perform automatic transfer tests: 4.11.2.2.4.1 Simulate loss of normal power. 4.11.2.2.4.2 Return to normal power. 4.11.2.2.4.3 Simulate loss of emergency power. 4.11.2.2.4.4 Simulate all forms of single-phase conditions. 4.11.2.2.5 Monitor and verify correct operation and timing. 4.11.2.2.5.1 Normal voltage sensing relays. 4.11.2.2.5.2 Engine start sequence. 4.11.2.2.5.3 Time delay upon transfer. 4.11.2.2.5.4 Alternate voltage sensing relays. 4.11.2.2.5.5 Automatic transfer operation. 4.11.2.2.5.6 Interlocks and limit switch function. 4.11.2.2.5.7 Time delay and retransfer upon normal power restoration. 4.11.2.2.5.8 Engine cool down and shutdown feature. 4.11.2.3Test Values 4.11.2.3.1 Insulation resistance test voltages and minimum values to be in accordance with Table 10.2. 4.11.2.3.2 Determine contact resistance in microfilm. Investigate any value exceeding 500 microhms or any values which deviate from adjacent poles by more than fifty percent (50 ) 5. SYSTEM FUNCTION TESTS 5.1 General 5.1.1 Perform System Function Tests upon completion of equipment tests as defined in Section 4. It is the purpose of System Function Tests to prove the proper interaction of all sensing, processing and action devices. 5.1.2 Implementation 5.1.2.1 The testing firm shall develop test parameters for the purpose of evaluating performance of all integral components and their functioning as a complete unit within design requirements. 5.1.2.2 The testing firm shall test all interlock safety devices for fail safe functions in addition to design function. 5.1.2.3 The testing firm shall propose methods to initiate the sensing devices. 5.1.2.4 The testing firm shall note the operation of alarms and indicating devices. 6. HERMOGRAPHIC SURVEY 6.1 Visual and Mechanical Inspection 6.1.1 Inspect for physical, electrical and mechanical condition. 6.1.2 Visually inspect for bus alignment. 6.1.3 Remove all necessary covers prior to scanning. 6.2 Equipment to be Scanned 6.2.1 Switches, busway, open buses, switchgear, cables, cable and bus connections, circuit breakers, rotating equipment and load tap changer or current carrying devices. 6.3 Provide Report Indicating the Following: 6.3.1 Problem area (location of "hot spot"). 6.3.2 Temperature rise between "hot spot" and normal or reference area. 6.3.3 Cause of heat rise. 6.3.4 Phase unbalance, if present. 6.3.5 Areas scanned. 6.4 Test Parameters 6.4.1 Scanning distribution systems with ability to detect 1.0 rise between subject area and reference at 30.C. 6.4.2 Equipment shall detect emitted radiation and convert detected radiation to visual signal. 6.4.3 Infrared surveys should be performed during periods of maximum possible loading but not less than ten percent (10%) of rated load of the electrical equipment being inspected. 6.5 Test Results 6.5.1 Temperature gradients of 1.0 to 3.0 indicate possible deficiency and warrant investigation. 6.5.2 Temperature gradients of 4.0 to 15.0 indicate deficiency; repair as time permits. 6.5.3 Temperature gradients of 16 C and above indicate major deficiency; repair immediately. *6.5.4 Provide photographs and/or thermograms of the deficient area as seen on the imaging system. *Optional 7. REPORTS 7.1 Provide three copies of report to the facilitys Engineering Officer of all devices tested as required by the scope. Notification to the facilitys Engineering Officer shall be submitted on conditions of equipment and system, including recommendations for corrective action as applicable. TABLE 7.t U.8. standard Bolt Torques for Bus Connections Beat Treated 8tee1-Ca-mium or Zina Plated GRADE SAE SAE SAE AE 1&2 5 6 8 MINIMUM TENSILE 64K 105K 133K 150K (P.S.I.) BOLT Torgue (Foot Pounds) DIAMETER 1/4 4.0 5.6 8.0 8.4 5/16 7.2 11.2 15.2 17.6 3/8 12.0 20.0 27.2 29.6 7/16 19.2 32.0 44.0 48.0 1/2 29.6 48.0 68.0 73.6 9/16 42.4 70.4 96.0 105.6 5/8 59.2 96.0 133.6 144.0 3/4 96.0 160.0 224.0 236.8 7/8 152.0 241.6 352.0 378.4 1.0 225.6 372.8 528.0 571.2 Silicon Bronse Fasteners* Torque (Foot Pounds) Diameter Non-Lubrioated Lubricated 5/16 15 1C 3/8 20 14 1/2 40 25 5/8 55 4C 3/4 70 6C *Bronze alloy bolts shall have a minimum tensile strength of 70,000 pounds per square inch. Aluminum Alloy Fasteners** Torque (Foot Pounds) Diameter Lubricated 5/16 8.0 3/8 11.2 1/2 20.0 5/8 32.0 3/4 48.0 **Aluminum alloy bolts "shall have a minimum tensile strength of 55,000 pounds per square inch. Satinless Steel Fasteners*** Torque (Foot Pounds) Diameter Lubricated 5/16 14 3/8 25 1/2 45 5/8 60 3/4 90 ***bolts, capecrews, nuts, flatwashers, locknuts: 18-8 alloy Belleville washers: 302 alloy TABLE 7.2 Insulation Resistance Tests On Electrical Apparatus and Systems Recommended Maximum Minimum Insulation Voltage Rating Minimum Resistance in of Equipment Test Voltage, de Megohms 250 Volts 500 Volts 25 600 Volts 1,000 Volts 100 5,000 Volts 2,500 Volts 1,000 8,000 Volts 2,500 Volts 2,000 15,000 Volts 2,500 Volts 5,000 25,000 Volts 5,000 Volts 20,000 35,000 Volts 15,000 Volts 100,000 46,000 Volts 15,000 Volts 100,000 69,000 Volts 15,000 Volts 100,000 Note: This table has recommended minimum insulation values identical to those in the NETA Acceptance Testing Specification for new equipment. Well maintained insulation in favorable ambient conditions should continue to provide these values.

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