REVELSTOKE - 8 YEAR DOWN. Applied to Equipment Instruction Number R Class-Group Generate Date: 11 March 2004

Transcription

1 Page 1 of 31 Planned Maint. Type Turbo file - Job Group 8Y-DOWN Lead Trade Applied to Equipment Instruction Number R Class-Group Generate Date: 11 March 2004 Isolation Zone Supersedes References J:\PS\mep\Maintenance Program\Reliability Centered Maintenance\Revelstoke\Turbo Files\Turbo Today\REV RCMT V9.mdb Technical File # Prepared by: Revision History: Reviewed by: Accepted by: EOR: Work Performed by: Date: W.O. # ALARMS If pressure continues to decrease - Check oil pressure switch the breaker will not be allowed to 63QC1 (alarm PY) & 63QC2 Alarm - Low Oil Press - Blk Cl close (2nd stage alrm) and if pressure continues to drop then will trip. (alarm SY - block close); Specclose@26.5Mpa, open@27mpa. - Check relay 63QC1X/C2X, flag relay 30-QL,annunc in cntrl rm. Found Left PY A PY B PY C SY A SY B SY C Flag_ _CR_ _UCB_ 63QC1X 63QC2X 30-QL

2 Page 2 of 31 ALARMS Alarm - Low Oil Press - Blk Re If pressure continues to decrease the breaker will not be allowed to close (snd stage alrm) and if pressure continues to drop then will trip. If alarm fails and pressure ALARMS continue to drop then get gas Alarm - Low SF6 Density Lev pressure density lev II. If lev II 1 fails then trip. - Check oil pressure switch 63QR1 (alarm PY) & 63QR2 (alarm SY - block reclose); Specclose@29.9Mpa, open@30.4mpa (as found, asleft for A,B,C ph). - Check relay 63QR1X/R2X, flag relay 30-QR,annunc in cntrl rm. - Check operation of gas pressure switch 63GA. Specified to close at 440kpa and open at 490 kpa. - Check operation of relay 63GAX. - Check operation of alarm in control room. - Check operation of flagging relay 30-GA. Found Left PY A PY B PY C SY A SY B SY C Flag_ _CR_ _UCB_ 63QR1X 63QR2X 30-QR Found Left open kpa kpa close kpa kpa Close Open 63GAX A 63GAX B 63GAX C Flag_ _CR_ _UCB_ 63GAX 30-GA

3 Page 3 of 31 ALARMS Will not be able to close breaker if pressure low and if pressure - Check oil pressure switch 63QM (start-stop oil pmp); Spec- Alarm - Oil Pmp Trub - Ex Tm gets too low, the breaker will auto-close@33.3mpatrip. ALARMS Alarm - Oil Pmp Trub - O/L ALARMS Alarm - Oil Pmp Trub - Sup Fl ALARMS Alarm - Trip Coil Supervision open@33.8mpa. - Check timer relay 6QMT - speced min, flag relay 30-QM,annunc in cntrl rm. Will not be able to close breaker - Pickup 49QMX. if pressure low and if pressure - Check flag relay 30-49, annunc gets too low, the breaker will auto-itrip. cntrl rm. Will not be able to close breaker - Pull FCB fuse (press off). if pressure low and if pressure - Check flag relay 30-27, annunc gets too low, the breaker will auto-itrip. cntrl rm. If alarm fails and trip coil fails - Open 8D1 and 8D2 and check then will not be able to trip for cct supervision alarm in breaker. control room. Found Left 63QM A 63QM B 63QM C 63QMT As Found Time (min) As Left Time (min) Flag _ _CR_ _UCB_ 6QMT 30-QM Flag _ _CR_ _UCB_ 49QMX Flag _ _CR_ _UCB_ FCB Complete

4 Page 4 of 31 ALARMS Trip - Low Oil Press Breaker will not trip when required. Effects will be failure of interrupters. ALARMS Trip - Phase Discrepancy Failure or phase discrepancy results in single phase if 1 or 2 phases of the breaker do not open or close. Effects are tripping of associated breakers. - Check oil pressure switch 63QT1 (trip PY) & 63QT2 (trip SY); Spec-close@24.5Mpa, open@25mpa. - Check relay 63QT1X/QT2X, flag relay 30-QT,annunc in cntrl rm. - Check timer relays 48-1 and Speced at 200 ms. Check timer relays and (speced@1 s) - Initiate phase discrepancy by jumpering appropriate 52a contact in series with 48-1/2 timer). Check flag Check operation of trip coil. Found Left PY A PY B PY C SY A SY B SY C Flag_ _CR_ _UCB_ 63QT1X 63QT2X 30-QT Found Left Indication Flag_ _CR_ _UCB Complete

5 Page 5 of 31 ALARMS Trip/Alarm - Low SF6 Lev 2 CONTROLS 52T1/2/C - coil resistance If trip fails and pressure continue to drop then will not have required gas pressure to extinguish arc. Also, will not get 86GTS trip and will not block close of breaker. Coil or contacts fail. Effects are not being able to open or trip the breaker. There is a PY and SY trip coil so it is assumed the beaker will likely trip when required. Also, the trip coils are supervised. There is only one close coil so when it fails, can not close the breaker. Likely due to wear/o/l. - Check gas pressure switch 63GL1PY/63GL2SY. (trip,blk close,opn mods). Spec - close - 390kpa; open kpa. - Check relays 63GL1X/2X, flag relay 30-GL,annunc in cntrl rm. - Check 86GTS, timed relays 63GL1T/63GL2T Check coil resistance. - 52T1 trip coil PY (specified at ohms). - 52T2 trip coil SY (specified at ohms). - 52C close coil (specified at 60 ohms +- 6 ohms) - Check contacts on each coil. SAI: Coil restsnace exceeds spec or contacts failed. Found Left PY A open kpa kpa close kpa kpa PY B open kpa kpa close kpa kpa PY C open kpa kpa close kpa kpa SY A open kpa kpa close kpa kpa SY B open kpa kpa close kpa kpa SY C open kpa kpa close kpa kpa Flag_ _CR_ _UCB_ 63GL1X 63GL2X Coil resistance Found Left 52T1 A ohms B ohms C ohms 52T2 A ohms B ohms C ohms 52C A ohms B ohms C ohms Complete A B C

6 Page 6 of 31 CONTROLS Timers (52Y, 27) CONTROLS Wiring and Terminals Failed coil, contacts or timing. Effects are loss of AC control voltage to the pump will result in alarm. For anti-pumping, effect is the close coil will stay energized while finger on button so in a trip free condition, breaker will attempt to close, repeatedly. Likely due to wear/ol/adjustment. Wire breaks down with age and O/L; Loose connections. Likely due to age/vibration. - Check timers 52Y and speced at 5 secs. - 52Y speced at 50 msec. - Check operation circuit for antipump SAI: Failed coil or timing out of calibration. - Check wiring for discolouration. - Check terminals for tightness. SAI: Loose terminations or discoloured wires. Found Left 27 52Y 6QMT GL1T 63GL2T Complete Complete Complete

7 Page 7 of 31 HYD SYSTEM Internal Oil Leakage Internal oil leakage specified at less than 0.5 Mpa per hour - refer to HBN HYD SYSTEM Nitrogen Pressure Pump will attempt to maintain pressure and will not. Effects are alarm, then trip. Likely due to age/wear/vibration. - Record breaker open-pump offtime (A, B, C phases). - Record breaker open-pump ontime (A, B, C phases). - Record internal leakage per hour (A, B, C phases).(4 hr period) - Record breaker closed-pump off-time (A, B, C phases). - Record breaker closed-pump on-time (A, B, C phases). - Record internal leakage per hour (A, B, C phases)(4 hr period) SAI: Leak rate exceeds spec. Leakage due to o'ring failure. - Check nitrogen pressure in the Effects are nitrogen back into accumulator (Mpa). Refer to hydraulics. Breaker will eventually drawing HBN trip on low oil pressure. - Record temperature. Likely due to age/vibration. - Spec: Min = 18 Mpa at 20 deg C. SAI: Does not meet spec. Open-pump Found Left off time A off time B off time C on time A on time B on time C leak/ hour A leak/ hour B leak/ hour C Closed-pump Found Left off time A off time B off time C on time A on time B on time C leak/ hour A leak/ hour B leak/ hour C Nitrogen Pressure Found Left _temp_ A B C

8 Page 8 of 31 HYD SYSTEM Oil Pump HYD SYSTEM Oil Pump O/L (49QMX) Failed check valve indicates increased number of pump operations and pump up time. Failed wiring, contactor, insulation, will result in misoperation which will cause an alarm and eventual trip on low pressure. Likely due to age/o/l. Pump trouble alarm and eventual trip if not fixed with low pressure. - Check oil pump start (from last inspection, left, and difference). - Megger the windings (at 500 VDC). - Check the wiring for tightness. - Check the contactor. - Check oil pump-up time (0 psi to full pressure). Compare against previous results. SAI: Does not pass megger. - Physically pull the lever on the O/L and confirm its operation. Note that this does not check that the O/L works at its rating, only that it functionally works. Number of operations: Prev._ _Found _Left _Diff'ce A B C Found Left A deg C deg C Mohms Mohms B deg C deg C Mohms Mohms C deg C deg C Mohms Mohms Complete A B C Complete A B C Pump-up time A B C Complete A B C INTERUPTER Contact Resistance - External Contacts, nozzles or linkage starting to fail. Effects are arcing, burning resulting in byproducts. Eventual trip on phase unbalance. Likely due to Adjustment/wear. - Check contact resistance using 100ADC ductor. Specification - not to exceed 250u-ohms. - Refer to attached ductor sheets. - Ductor between points D - F (as found and as left). SAI: Does not meet spec. Contact resistance: Found Left D-F AØ D-F BØ D-F CØ INTERUPTER Insulators Insulation failure due to tracking (contamination). Effects are flashover to ground. Likely due to age/contamination. - Complete doble test. SAI: Does not pass doble test. Complete Attach Results

9 Page 9 of 31 INTERUPTER Timing Tests Failed valve, friction in linkage, interupter alignment Likely due to wear/age. Complete timing test at beginning of outage for maintenenance completed on the outside (non SF6 component inspection) and completed timing test at the beginning and end when maintenance is completed on the inside of the chamber. T1-T4 on close operation T5 - T7 on trip operation T8 - T10 on Close/Open Operation T1: ms (A, B, C phases) From: close coil initiation To: main contacts close T2: T5 : 16ms +/- 1 ms (A, B, C phases) From: trip coil initiation PY To: main contacts open SY T8: (A, B, C phases) From: close coil initation To: last main contacs close T9: (A, B, C phases) From: first phase close To: last phase close T10: (A, B, C phases) (On Close- Open Operation) From: first main open To: last main open. SAI: Does not meet spec. T1 on close operation Found Left A B C T2 on close operation Found Left A B C T5 on trip operation Found Left A B C T8 on close/open operation Found Left A B C T9 on close/open operation Found Left A B C T10 on close/open operation Found Left A B C OP MECHANISM Pins and LInkages Broken pin or linkage. Effects are not being able to open or close the breaker. Likely due to Metal Fatigue. - Check pins and linkages for cracks or fractures. SAI: Cracked or fatigued linkage Complete A B C

10 Page 10 of 31 REV - DRAFT TUBE GATES DRAFT TUBE GATES Seals Water leakage: REV - EXCITER BRIDGES Snubbers REV - EXCITER BRIDGES Terminals and Wiring Increasing leakage when gate in closed position due to worn or damaged seals. Likely due to Wear & Tear. Fast rise transients with damage reverse blocking capability of the thyrisor. Effects are possible failure of the thyrsitor. Loose wiring. Effects possible are exciter misoperation. Likely due to vibration/age. Measure and record gate leakage coming out of beam pocket doors. Discount draft tube dewatering valve leakage by opening valve to sump. SAI: excessive leakage - Bridges 1-8 (a,b,c,d). - Visually check snubbers for overheating. - Check with an ohmmeter. Refer to pg 13-2 of the Westinghouse Maint / Op manual. - Check tightness of connections. - Blow then out with compressed air. - Check wiring for loose terminations and discolouration. SAI: Loose or damaged wiring a b c Complete Complete Complete REV - EXCITER COOLING SYSTEM Fan Blades and Guards Blades and fans become loose and unbalanced. Effects are failure of the bearing. Likely due to Mechanical. - Check that the fan blades and guards are secured. SAI: Loose fan blades Complete

11 Page 11 of 31 REV - EXCITER EXCITATION TRANSFORMER Alarm - Trans O/T RTD (26A- F) Would get an alarm (at 120 deg C) from the bulb if RTDs fail - Use Fluke RTD checker and confirm that RTD is good. - Check FLuke RTD value against actual readout at UCB. - If readout not correct, then recalibrate WX/WD cards. - Use decade box to check alarm at 90 deg C ( ohms). - Alarm #45 at 90 deg C. _Resis._ _Deg C 26A A 45 26B B 46 26C C 47 26D A 40 26E B 41 26F C 42 Complete REV - EXCITER FIELD FLASH 31VR Relay REV - EXCITER FIELD FLASH Diodes REV - EXCITER FIELD FLASH Snubber Components REV - EXCITER FIELD FLASH VoltTraps Failed coil, contacts, fuses and connections. Effects are an alarm - AC field flash power supply failure. Likely due to heat/ol/vibration. Can not field flash the unit. Damage to components caused by transients. Failure of voltraps could damage the field flash transformer. Calibrate relay - Pick-up at 130 VDC - Drop out at 110 VDC. SAI: Does not pick up or drop out as speced. Ohmeter check for continuity and reverse blocking ability (one on AC field flash, 2 on DC field flash). - Visual check (2 sets per phase). - Examine for overheating, surface tracking, dust accumulation. - Ohmmeter check for continuity (one on AC, one on DC). Found Left PU DO AC Field Flash DC Field Flash DC Field Flash Complete Complete AC Complete DC Complete REV - EXCITER PROTECTION DC Voltraps Overvoltage on DC bus during pole slip. Effects are damage to the thyristor causing fuse or thyristor. - Examine for overheating, surface tracking, dust accumulation. - Bridges 1-4, 5-8. Complete Complete

12 Page 12 of 31 REV - GEN TERM EQU Switch contact resistance high or - Check Operation of aux. Complete A B C DISCONNECT SWITCH (16D1) fail to close or open when required. Effects are that the switch. - Check Travel Adjustment Complete A B C Complete A B C 16D1 - Auxiliary Switch motor can not be used to open or - Check Limit Switch Condition Complete A B C close the disconnect and it must - Check Connections Tight be operated manually. REV - GEN TERM EQU DISCONNECT SWITCH (16D1) 16D1 - Motor/Gearbox Likely due to wear/o/l. Breakdown of the winding due to overheat. Failure of the gear box (note gearbox common to both manual and electric close). Effects are that the disconnect can only be opened manually. If gear box fails, can not open or close switch. Likely due to mechanical/o/l. SAI: Out of adjustment. - Megger - Inspect Brushes for Sparking, Wear - Overheating - Vibration, Noisy Operation - Low Speed Stop Adjustment - High Speed Stop Adjustment (5% Above Rated Speed) - Inspect Pulleys, Drive Belts, Splines - Bearing Lubrication - Inspect Gear Box and Lubricate - Alignment - Inspect and Lubricate Drive Gears - Operation of Manual/Electrical Clutch (motor brake). deg C Mohms Complete A B C Complete A B C Complete A B C Complete A B C Complete A B C Complete A B C Complete A B C Complete A B C Complete A B C Complete A B C Complete A B C REV - GEN TERM EQU DISCONNECT SWITCH (16D1) 16D1 - Wiring Discolouration or breakdown; High resistance. Effects are that the disconnect will have to be closed manually. Likely due to O/L/Age. SAI: Poor megger or poor inspection results. - Check Knife Switch Condition Complete A B C - Check Fuse Condition Complete A B C - Check Connections Tight Complete A B C - Check Terminal Block Complete A B C - Check Ground Connections are Complete A B C Tight SAI: Faulty wiring or loose terminations

13 Page 13 of 31 REV - GEN TERM EQU DISCONNECT SWITCH (16D1) 16D1 (Switch) Complete A B C Complete A B C Flashover (trip) or fail to close/open due to misadjustment. Effect is that if fail open then fail to start. If flashover then repair required resulting in lost generation Likely due to mechnical. - Inspect contact surfaces for scoring, pitting and galling. - Inspect contact surface for loss of silver plating. - Check contact finger pressure (specified 35 lbs +-5lbs). - Check contact spring height (specified to inches). - Check sliding conductor alignment. - Check sliding conductor closed gap (specified 0.25 to 0.36 inches). - Check sliding conductor open gap (specified to inches) - Check open and close stops (specified gap 0.18 inches). - Clean contacts and apply new conductive contact grease. - Inspect insulators for cracks, and damage. SAI: Out of alignment, contact damage, wear, finger pressure and damage on the surface of the sliding cn. A B C lb A B C in Complete A B C A B C in A B C in A B C in Complete A B C Complete A B C

14 Page 14 of 31 REV - GEN TERM EQU GROUND SWITCH 16GD1/2/3/4 - Switch Out of alignment, binding. If in the closed position then can not generate. Likely due to mechanical. Before making adjustments and performing the inspection on the ground switches, the power springs must be blocked. See maintenance and instruction manual for the procedure. - Inspect Contact Finger Surfaces - Contact Finger Pressure (24 lbs Each Contact) - Switch Blade Alignment - Upper Mechanical Stop (Clearance to Main Shaft 1/4 to 3/8 inch) (approx.) - Inspect Primary Spring - Inspect Booster Spring - Inspect Linkages - Inspect Primary Connections - Inspect Primary Bushings - Inspect Ground Bus and Ground Connections - Check All Bolts Tight - Ductor from moving contact to remote ground at gen flex links. Complete A B C A B C lb Complete A B C A B C in Complete A B C Complete A B C Complete A B C Complete A B C Complete A B C Complete A B C Complete A B C Complete A B C SAI: Make adjustments, finger pressure, mechanical stop

15 Page 15 of 31 REV - GEN TERM EQU GROUND SWITCH 16GD1/2/3/4-Interphase Linkage Worn chains/sprockets/gears. Drive shafts have failed in the past. Effects are loss of generation of the switch is in the closed position after maintenance and it can not be opened. Likely due to wear. Before making adjustments and performing the inspection on the ground switches, the power springs must be blocked. See maintenance and instruction manual for the procedure. - Inspect Bearings - Lubricate Bearings - Inspect Gears and Drive Studs - Lubricate Gears - Inspect Interphase Drive Shafts - Inspect Universal Joints (Allan Screws Tight) - Check Operating Handle - Check Chain Sprockets - Lubricate Chains SAI: sprocket/chain/drive shaft damage Complete A B C Complete A B C Complete A B C Complete A B C Complete A B C Complete A B C Complete A B C Complete A B C Complete A B C REV - GEN TERM EQU ISOLATED PHASE BUS Insulators - visual Tracking on the insulator or breakdown (cracks). Effects are possible flashover, protection trip and consequential damage. Likely due to heat/dirt/dirt. For the insulators that can be reached or seen in the bus duct. - Take off plates to gain access. - Clean surface of the insulator. - Check bus duct enclosure for cracks or damage paint. - Check for cracks or defects in the insulator. - Clean and vacuum. Complete A B C Complete A B C Complete A B C SAI: cracked insulator or showing tracking

16 Page 16 of 31 REV - GEN TERM EQU VT/SA/CX CUBICLES CX (Capacitors) Complete A B C Short to ground; O/L. Effect is without the capacitor that there will be no protection to limit the slope of the transient wave front on the stator windings. The unit will trip on short to ground. Likely due to vibration/o/l. - Inspect Bushing for Cracks, Damage - Check Surface Clean - Check Connections Tight - Check Inspect Ground Bus - Check Inspect Ground Bus Insulator for - Check for Cracks, Damage - Check Mounting Bolts Tight Complete A B C Complete A B C Complete A B C Complete A B C Complete A B C Complete A B C REV - GEN TERM EQU VT/SA/CX CUBICLES SA (Surge Arrestors) Short to ground; O/L. Effects are not having surge protection to limit the surge voltage on the generator terminals. The unit will trip on short to ground. Likely due to vibration/o/l. SAI: Does not pass inspection - Inspect Bushing for Cracks, Damage - Check Surface Clean - Check Connections Tight - Inspect Ground Bus - Inspect Ground Bus Insulator for Cracks, Damage - Check Mounting Bolts Tight Complete A B C Complete A B C Complete A B C Complete A B C Complete A B C Complete A B C SAI: Does not pass inspection

17 Page 17 of 31 REV - GEN TERM EQU VT/SA/CX CUBICLES VTs (Voltage Transformers) Short to ground; O/L; Failed fuse resulting in loss potential. Effects are governor goes into actuator lock for loss of potential from 16VT2 and the exciter transfer into manual. Loss of potential on 16VT1 will result in alarm (83PFB) and will affect protective relay operation. Unit should be removed from service at this time. Likely due to vibration/o/l. - Megger - Complete Ratio Test - Check Connections Tight. - Check condition of drawout contacts (primary and secondary). - Check condition of drawout mechanism. - Check condition of barriers. - Check bus support Insulator condition - Check current limiting Fuse Condition - Check Mounting - Check Structural Damage - Clean deg C Mohms Complete A B C Complete A B C Complete A B C Complete A B C Complete A B C Complete A B C Complete A B C Complete A B C Complete A B C Complete A B C REV - GENERATOR LIFT PUMP SYSTEM Pressure Relief Valve (PRV) Worn seat or broken spring can cause PRV to fail causing relief of High Pressure Unit (HPU) at too low or too high values. Built in pilot mechanism can cause failure. Likely due to Wear & Tear. SAI: Does not pass ratio test or damage evident upon inspection; Damaged fuse. Start pump and check that valve operates at /- 50 psi by closing downstream valve. Check for leaks. SAI: PRV opens at incorrect pressure. Valve operation point Found Left psi psi Complete

18 Page 18 of 31 REV - GENERATOR TH GD BEARING Lower Bracket, Brg, & Bolts 36 - M20 Bolts 40 - M100 Bolts Mounting bolts loosening, structural failure of bearing shell resulting in failure to restrict lateral movement- rotor contact with the stator would be catastrophic. Likely due to Fatigue. - Visual inspection and checking for missing or loose bolts (lock tabs) - 36 M20 sole plate bolts, and 40 M100 bolts holding lower bracket arm. Specified torque for M100 is 120,000 to 150,000 kgcm (8,680 to 10,850). - Measure & record gap from spring to guide plate. - Foundation: visual inspection for cracks or concrete dust around sole plates, also visible fretting between lower bracket arm and sole plate. SAI: Loose or missing fasteners, cracks. Gap distance: Complete REV - GENERATOR TH GD BEARING Oil Coolers REV - INTAKE GATES CNTL'S-STATIC TESTS Pressure Switch (63WP) Corrosion of coils causing coil failure then water in the oil / loss of lubricity, oil in the water can potentially cause environmental damage. Likely due to corrosion. Gate will not raise above 3" Likely due to age/vibration/fault. - Remove end covers and use ultrasonic equipment to measure wall thickness. - Check for leaks. SAI: tube wall thickness below safe operating value Use Druck to test that pressure switch operates at 150 +/- 5 psi on rising pressure. SAI: incorrect operation Complete Complete Found Left psi

19 Page 19 of 31 REV - INTAKE GATES Loss of system control. Possible 1. Check operation of relays Complete CNTL'S-STATIC TESTS Relays & Timers loss of restore operation. Likely due to age/vibration/fault. 2. Check timing of relays Found Left 2IGF TDPU - 20 min (fill timer) 2IGS TDPU - 10 sec. (seating timer) 2IGD TDPU - 5 sec. (gate droop alarm) 2IGR TDPU - 5 sec. 2PB TDDO - 1 sec. (seal in) 2CL TDPU - 5 sec. (crack limit timer) s s s s s s SAI: incorrect operation or timing REV - INTAKE GATES HPU - AUXILLARY Auxiliary Hydraulic System REV - PENSTOCK PENSTOCK Drain Valve - Actuator Fails to operate gate when required. inoperable or stuck valve caused by electric motor or control failure Likely due to age/vibration/fault. Start motor: check vibration/noise, suction filter, both PRV settings (350 & 2200 psi), clean contactor, and test operation. Megger motor, plot in-rush current to determine if mechanism operation becoming sticky. Consider recording time for valve to open and close. SAI: bad megger (< 1 Meg ohm) or current trending up Complete Valve: to open s to close s

20 Page 20 of 31 REV - PENSTOCK TRASHRACK Bars Report to File Debris enters turbine due to missing bars caused by corrosion or cracking Likely due to Age/Wear. Visual inspection of trashrack to assess corrosion and identify any cracks or missing bars. SAI: Severe corrosion, cracks or missing bars. REV - TRANSFORMERS CONTROLS Alarm - Mech Trip Blk Sw (29T) No alarm when the switch is left in the "open" position. Switch blocks all transformer mechanical device trip ccts. - Close switch to enable mechanical trips and remove alarm condition. - Open switch to confirm alarm. Complete Indication Flag CR UCB REV - TRANSFORMERS HV BUSHING Bushing Press Hi/Low (63QB/H) REV - TRANSFORMERS HV BUSHING Insulation - High or Low bushing pressure, arcing. Arcing and tracking Likely due to age/vibration/moisture/surface contamination. - Check oil level. - Verify alarm; Jumper at device to test alarm. - Verify pressure that switch operates psi (265 kpa) for alarm. Note that bushing pressure alarm flags at local cubicles in CB gallery. - Obtain oil quality sample and gas in oil sample and send away for analysis to Powertech (lower connection). Ensure that the accepted procedures are followed. - Complete Doble test. Refer to Maint. Std Test to include both A.C. dielectric loss and Power Factor Method. Complete Complete Operates at PSI Indication Flag CR UCB Complete Complete Attach Results SAI: poor test results

21 Page 21 of 31 REV - TRANSFORMERS LV BUSHING Insulation Arcing and tracking Likely due to age/moisture, cleanliness, PD. Complete Attache Results - Complete Doble test. Refer to Maint. Std Remove shrouds and flex links to gain access and connect doble test instrument. Test to include both A.C. dielectric loss and Power Factor Method. SAI: poor test results REV - TRANSFORMERS NEUT. BUSHING Insulation Arcing and tracking Likely due to age/vibration. - Complete Doble test. Refer to Maint. Std Test to include both A.C. dielectric loss and Power Factor Method. SAI: poor test results Complete Attach Results REV - TRANSFORMERS OIL - INSUL. Oil Temp Gauge REV - TRANSFORMERS OIL PUMPS Overloads (O/L) No movement of gauge with respect to transformer loading. Likely due to mechanical breakdown. Oil pump will not operate. - Use Browman block to test gauge operation. SAI: - Indication is not correct. - Check overload operation and correct setting to motor. - Crank down O/L and operate pump to confirm operation and current for trip. - Reset and readjust O/L. Complete O/L Setting: Pump: #1_ _#2 A B C O/L setting down operation: Pump: #1_ _#2 A B C Replaced: Yes No

22 Page 22 of 31 REV - TRANSFORMERS TANK Trip - Tank Press Rel Tank begins to leak, trip of unit due to electrical fault. Complete Complete - Visual inspect on front of device for leaks. - Inspect connections, etc of the Qualitrol # pressure relief device. - Confirm oil pump cutoff with operation of relief device (86GTS,3063Q). Complete REV - TRANSFORMERS TRIPS Trip - Low Cons Lev + Gas Accu REV - TURBINE DRAFT TUBE Elbow and Pier Noses REV - TURBINE HEAD COVER High Water Alarm Transformer does not trip when - Verify trip cct. Complete there exists low cons oil level and gas accumulation. spalling of concrete, cavitation, wear due to: Likely due to Age/Wear. fails to indicate excessive water level in turbine pit Visual inspection for concrete erosion or other damage. SAI: exposed rebar or other damage 71WTH - high alarm #27 U1 F3 TB1 PA7-WBH, closes 165mm, reset 160mm. Report to File Found _Left c'ct closes mm c'ct reset mm REV - TURBINE SHAFT SEAL Bolts & Brackets REV - TURBINE SPIRAL CASE Cooling Water Trash Bars Excessive water leakage or rub on shaft due to movement of shaft seal assembly. Likely due to Fatigue/vibration. Bars become loose due to cracked welds, possibly leading to runner damage or cooling water inlet becoming plugged. Likely due to Fatigue/vibration. DWG's H04-WD4755, M04- WC4312 Visual inspection and check for missing or loose bolts, cracked welds, corrosion. Record seal height indication. SAI: Loose or missing fasteners, cracks. Visual inspection for missing bars. SAI: screen or part of screen missing Complete Seal height Evidence of missing bars Yes No

23 Page 23 of 31 REV - TURBINE SPIRAL CASE Penstock Drain Trash Bars Loose Bar: Yes No REV - TURBINE TURB BRG Bolted Connect'n to Head Cover REV - TURBINE TURB BRG Temperature - RTD Bars become loose due to cracked welds, will eventually break off possibly leading to runner damage or penstock drain becoming plugged. Likely due to Fatigue/vibration. Mounting bolts loosening, structural failure of bearing shell resulting in failure to restrict lateral movement - runner contact or wiped bearing. Likely due to Fatigue. Fail to indicate correct temperature reading due to RTD or conditioning card failure. Likely due to: Likely due to age/vibration/fault. Visual inspection for cracks. Check by hitting each bar with a hammer to see if the bar rings or is dead. SAI: loose bars, cracked weld Visual inspection and checking for missing or loose bolts (lock tabs), structural failure, corrosion. Consider using cracked paint as an indicator of movement or stress. Record any damage found. SAI: Loose or missing fasteners, cracks. Check temperature reading at UCB to check operation of RTD. Simulate RTD with resistive decade box, check calibration of WX & WD condition cards. Connected to OI and UCB. - 38TGR1 - bearing pad alarm #75 U1 F1 04A - 04B - 04C, JB TA1 close at 75 deg C (11.93 ohms). RTD# TGR2 - bearing pad alarm #75 U1 F1 05A - 05B - 05C, JB TA1 close at 75 deg C (11.93 ohms). RTD#5. SAI: incorrect temperature reading Complete Found Left Alarms: 38TGR1 deg C 38TGR2 deg C

24 Page 24 of 31 REV - TURBINE TURB BRG Water Deflector Complete REV - TURBINE WICKET GATES Bolts and Pins REV - GENERATOR LIFT PUMP SYSTEM AC Supervision (88V) REV - GENERATOR LIFT PUMP SYSTEM Press Sw - 63QTH psi Water in bearing pot from deflector coming loose from shaft due to deflector bolts loosening or breaking Likely due to Fatigue/vibration. Sticky or inoperable wicket gates due to binding from broken or loose mounting connections. Likely due to Fatigue/vibration. Lift pump not operating because of supply failure. Unit fail to start because of 63QTH psi start interlock. Failure or calibration problem with switch. Will cause failed unit start sequence. Likely due to Adjustment/malfunction. Visual inspection of bolts, check locking tabs. Record any damage found. SAI: broken tabs or loose bolts Visual inspection of collar, link, and cover plate bolts, shear lever tension nut, pin lock plates, and keys, eccentric pin, and shift ring split ring bolts. Look for broken paint or other signs of movement. Record any damage found. SAI: loose or broken bolt Check that relay 88V picks up correctly when AC power shut off. Check that 88V neon supv. F5 illuminates. Pressure switch tested with Anatek and Druck test equipment. - Test that 63QTH1 (start interlock) PU at /- 50 psi, DO at /- 50psi. Check that 63QGT1 picks up and neon supv. F4 comes on. - Check alarm operation pt. #21, drop out at 1500 psi. Check annunciationat the UCB, Control Rm and SIC. See dwg H04-D435 SAI: switch closes at incorrect pressure. Complete Complete 63QTH1 Found Left PU psi psi DO psi psi 63QGT1 picks up Indication #21 UCB C.R. SIC

25 Page 25 of 31 REV - GENERATOR LIFT PUMP SYSTEM Press Sw - 63QTH psi Pressure too low due to calibration problem. Likely due to Adjustment/malfunction. REV - GENERATOR LIFT PUMP SYSTEM Pressure Gauge REV - GENERATOR NEUTRAL CUBICLE Alarm and Trip - Neut Res O/T Incorrect indication of oil pressure would lead to confusion about operating pressure. Likely due to Adjustment/age/malfunction. Loss of liquid in bourdon tube, contact failing to close, calibration of temp probe. Switch is tested with Anatek and Druck test equipment. - Test 63QTH2 pressure failure alarm 1200 psi, 1000 psi. with falling pressure. - Check alarm operation pt. #21, drop out at 1000 psi. Check annunciationat the UCB, Control Rm and SIC. Jumper W.S. input wire WBB, mtce section 16 to check alarm at Control Rm and SIC. SAI: switch closes at incorrect pressure (+/- 50 psi) - Check calibration and condition of pressure guage at 1500 psi with Druck test equipment. Calibrate if out by more than 50 psi. SAI: out by more than 50 psi - Check tube probe with Browman heat block - Check when contacts close with meter (Alarm pt 17@45 deg C, term HT3,4 for 26GN2 and Trip 125 deg C, term HT1,2 for 26GN1 ). Record temp when contacts close and annunc at 3 locs. Check flag 36-26GN 63QTH2 Found Left PU psi psi DO psi psi Indication #21 UCB C.R. SIC Found Left psi psi Found_ _Left Alarm/Trip deg C Cct close deg C UCB C.R. SIC Flag 30-26GN

26 Page 26 of 31 REV - GENERATOR STATOR HOUSING RTD - Housing Air Complete Fail to indicate correct temperature reading due to RTD or conditioning card failure. Likely due to age/vibration. Check temperature reading at UCB to check operation of RTD. Simulate RTD with resistive decade box, check calibration of WX & WD condition cards (10 25 deg C, deg C). Locate the decade box right at the RTD which is located on "I" beam above rotor. Record RTD resistance and temperature and confirm operation of alarm at UCB, Control Rm and SIC. Note that after field initiation of alarms at the UCB, jumper the W.S input wires to PA7 (P.H.) or P89 (S.S.) to check the alarms at the control room and SIC. Note: the "bit", a toggle switch, must be turned on prior to jumpering the unblock the alarms at SIC. 26AGHR - Alarm point # 80, Alarm at 70 deg. C deg C, (11.93 ohms) term. 295,296 Jumper W.S. input wire WD7, mtce section 1,7,8,9 to check alarm at Control Rm and SIC. SAI: Out of calibration Alarms at Temp Ohms 26AGHR UCB_ _CR_ _SIC_ 26AGHR

27 Page 27 of 31 REV - GENERATOR TH GD BEARING RTD's Complete REV - GENERATOR WINDING RTDs - Stator Winding Fail to indicate correct temperature reading due to RTD or conditioning card failure. Likely due to age/vibration. Broken lead; open RTD; WX/WD card out of calibration. Likely due to age/vibration/faulty card. See attached Electrical Maintenance Procedure: Generator Bearing - RTD Checks. SAI: incorrect temperature reading See attached Electrical Maintenance Procedure: Generator Stator Windings - RTD Checks. Complete REV - GENERATOR ROTOR Amortisseur Windings Lamination burning on pole face as a result of high resistance joint or unbalanced operation of generator. Effect could be operation of the phase unbalance relay. Likely due to age/vibration/fault. SAI: no meaningful reading - replace card; 5-10% off reading - recalibrate. - Visually inspect in air gap looking at the face of the pole. - Use fiberscope and inspect pole face to detect damper bar migration and damper slot burning. SAI: burning/discolouration on pole face or bar dislocation Complete Complete

28 Page 28 of 31 REV - GENERATOR VIBRATION MONITOR Vitec Monitor Loss of meaningful vibration output; receive cct supervision alarm due to generic failure; loss of local display (meter module); loss of signal to O/I & SCADA and alarms. Likely due to Adjustment/age/malfunction. Inject known signals and measure output; refer to the electricians booklet (test booklet) which includes the list of input and output signals expected. (1) Alarms: 13A Gen Sync "X" - 7mils. Reset 13B Gen Rough "X" - 5 mils. Reset 13C Gen Sync "Y" - 7 mils. Reset 13D Gen Rough "X - 5 mils. Reset 14A Turb Sync "X" - 10 mils. Reset 14B Turb Rough "X" - 10 mils. Reset 14C Turb Sync "Y" - 10 mils. Reset 14D Turb Rough "Y" - 10 mils. Reset (2) DC Voltage Adjust: 24 V (R15) TBO 1-2. DC Voltage Adjust: 12 V (R25) TBO 1-3. (3) Record Notch and Bandpass Filter Characteristics from 0.8 Hz to 4 Hz - refer to test booklet for instructions; record displacement for points 13A to 14D. SAI: Incorrect output or alarm Found Left 13A 7mils 13A reset 13B 5mils 13B reset 13C 7mils 13C reset 13D 5mils 13D reset 14A 10mils 14A reset 14B 10mils 14B reset 14C 10mils 14C reset 14D 10mils 14D reset 12V tbo V tbo 1-3 Complete

29 Page 29 of 31 REV - GOVERNOR ACCUMULATOR TANKS Oil Tank Lev Relays (71QPA&T) Accumulator Tank High Level Alarm due to make up air compressor not coming on. 71QPA closes Found Left in_ in Likely due to Mechanical/Wear. - Increase oil level. - Put meter on level switch (71QPA). - Make-up comp air comes on - O.P. AJ 3-4; Closes at 71.5" (1,806 mm) and Opens at 71.0" (1,803 mm). - Lower the oil level. - 71QPA opens and drops out agastat (71QPAT) min +- 1 min the pump will drop off. 71QPA opens Found Left in_ in Agastat 71QPAT drops out Found Left min_ min REV - GENERATOR BRAKE SYSTEM Priority Valve Control REV - GOVERNOR ACCUMULATOR TANKS Tank Relief Switch (63AR) REV - GOVERNOR CONTROLS Gate Limit Motor Brushes 65GLM Low air pressure - auto start failure or failure to stop if unit is running. Likely caused by failure of compressor priority valve or compressor system. Likely due to Fatigue/vibration. High pressure in tank resulting in leaks and fast response of wicket gates. Unit will not start or will limit output due to GL motor failure from brush pitting, shorter brush length, or burning. Likely due to wear / overload. SAI: Relay does not work - Test that the priority valve 92 psi +/- 3 psi. SAI: incorrect operation of priority valve - Check that pressure switch operates at psi (4.75 MPa kpa). - Use druck. - Check alarm #35 (terminal G.O. AA13-14) - Remove one brush and check relative wear compared to other machines. - Measure length of brush and record. SAI: excessive wear or pitting Priority Valve Found Left psi psi 63AR Found Left psi _ psi Complete Found Left mm _ mm Complete

30 Page 30 of 31 REV - GOVERNOR CONTROLS Gate Restore Cable & Shaft Complete Erratic governor operation caused by sticky or jammed gate restore connection to governor. Likely due to Loss of lubrication, breakage of a mechanical part. - Grease sheaves and restore shaft. Visual inspection of cable and clamps. Open one sheave to determine if they all need cleaning. REV - GOVERNOR CONTROLS Shutdown Solenoid (65SD) Inadvertent closing of wicket gates and shuts down unit through 3SD & 4B (auto stop). Likely due to malfunction / adjustment. SAI: frayed or damaged cable - Visually inspect; look for broken plastic spacers. - Functionally check operation. - Check for mechanical operation at the actuator cubicle. - Check for applied indication at the UCB. SAI: broken spacers, not picked up functionally Evidence of broken spacers: Yes No Complete Complete Complete REV - GOVERNOR HYDRAULIC AMPLIFIER 200psi Oil Pressure Gauge REV - GOVERNOR HYDRAULIC AMPLIFIER 90psi Oil Pressure Gauge Incorrect oil pressure reading. Likely due to Adjustment/malfunction. Incorrect operation of hydraulic amplifier from too low of oil pressure due to pressure gauge out of calibration. Likely due to Adjustment/malfunction. Check calibration of pressure gauge with Druck at 200 psi. Adjust or replace gauge if out by more than 10 psi. SAI: gauge reading out by more than +/- 10 psi. Check calibration of pressure gauge with Druck at 90 psi. Adjust if out by more than 5 psi. SAI: out of calibration by greater than +/- 5 psi Found Left psi_ psi Found Left psi_ psi

31 Page 31 of 31 REV - GOVERNOR OIL PUMPS Alarm - 6Q1/2 - #1/2 Lag Run Operating with only one main pump therefore only a single contingency. Low oil pressure alarm. #1 lag alarm #37 - Turn off lead pump (#1). - Jumper switch to operate lead pump. - Lag pump should start and should get #1 Lag Run alarm. - Repeat with pump #2. - #1 lag (terminals O.B. 1 C.C ) - Alarm #37. - #2 lag (terminals O.B. 1 C.C. 8-29) - Alarm #37. #2 lag alarm #37 REV - GOVERNOR OIL SYSTEM Piping low sump alarm due to oil leaking from pipe or valve Likely due to Fatigue/vibration. Visual inspection of all oil and air piping on and under sump tank, around accumulator tanks and gate locks. Combine with task for greasing cable sheaves. SAI: leak found Evidence of leak Yes No REV - GEN TERM EQU ISOLATED PHASE BUS Generator CTs & CT Junct Box REV - INTAKE GATES INOG Gate Posn Cable - gate shaft REV - TURBINE WICKET GATES Shear Pin Effects are possible flashover and loss of protection. Likely due to heat/dirt/dirt. Does not operate or indicated incorrect gate position due to corrosion or broken connection to intake gate. Likely due to Corrosion. High vibration or efficiency loss due to WG loose and not in line with flow directed into the runner by the stay vanes. Likely due to overload, sticking in guide and if fail will not a. - Check wire connections. - Check broken wires. - Check cracking of insulation. SAI: cracked insulator or showing tracking Visual inspection of cable connection to intake gate. SAI: damaged or sticky operation - Check shear pins to confirm that if one should break, the switch will cause an alarm. - Check for broken shear pins. SAI: shear pin stuck or broken Complete A B C Complete A B C Complete A B C