ML13330A383
| ML13330A383 | |
| Person / Time | |
|---|---|
| Site: | San Onofre  |
| Issue date: | 08/19/1981 |
| From: | Moody W Southern California Edison Co |
| To: | Crutchfield D Office of Nuclear Reactor Regulation |
| References | |
| NUDOCS 8108240222 | |
| Download: ML13330A383 (17) | |
Text
Southern California Edison Company P. 0. BOX 800 2244 WALNUT GROVE AVENUE ROSEMEAD. CALIFORNIA 91770 W. C. MOODY TELEPHONES MANAGER, NUCLEAR LICENSING August 19, 1981 (213) 572-1817 (213) 572-1806 Director, Office of Nuclear Reactor Regulation Attention:
D. M. Crutchfield, Chief Operating Reactors Branch No. 5 Division of Licensing U. S. Nuclear Regulatory Commission UOS. NUARREGULAT0U Washington, D.C.
20555 COMMISSM Gentlemen:
Subject:
Degraded Grid Voltage and Adequacy of Station Electrical Distribution System Voltages San Onofre Nuclear Generating Station Unit 1 Your letter of March 24, 1981, requested information for your review of the subject generic issues. Our response to your request is provided in Enclosures 1 and 2 of this letter. As discussed with your staff, submittal of this information has been delayed due to a change in the tap setting of the station transformers.
If you have any questions on this information, please let us know.
Very truly yours, Enclosures 8108240222 810819 PDR ADOCK 05000206 P
ENCLOSURE 1 Response to NRC Questions Concerning Degraded Grid Voltage San Onofre Unit 1 Reference 1:
NRC letter from A. Schwencer to J. B. Moore dated June 3, 1977 Reference 2:
SCE letter from K. P. Baskin to A. Schwencer dated November 4, 1977 Reference 3:
IEEE Standard 279-1971, "Criteria for Protection Systems for Nuclear Power Generating Stations" Item 1 Reference 1, Staff Position 2, states that in the event the load shedding feature is retained, the setpoint values of voltage and time in the Technical Specifications must be specified having maximum and minimum limits (+).
Reference 2, page 7, defines the setpoints for the CV-7 relay (4160 volt bus) at 82 volts with a time dial setting of 1.2. Submit the maximum and minimum
(+) voltages and time setpoints.
(Refer to Model Technical Specifications Table 3.3-4 of Reference 1.)
Response
The setpoints for the CV-7 relays on the 4160 volt buses at 82 volts with a time dial setting of 1.2 are 2870 + 92 volts with a 1.0 + 0.05 second time delay at 0 volts. These values are based on the manufacturer's catalogue and time-voltage curves for CV-7 relays.
Item 2 Reference 2, page 7, defines the setpoints for the CV-6 relay (4160 volt bus) at 105 volts with a time dial setting of 2.3. Submit the maximum and minimum
(+) voltages and time setpoints for the CV-6 relay.
(Refer to Model Technical Specifications Table 3.3-4 of Reference 1.)
Response
The setpoints for the CV-6 relays on the 4160 volt buses at 105 volts with a time dial setting of 2.3 are 3675 + 116 volts with a 12.0 + 0.6 second time delay at 0 volts. These values are based on the manufacturer's catalogue and time-voltage curves for CV-6 relays.
Item 3 Reference 2, page 10, item e, refers to the existing undervoltage protection not satisfying requirements of IEEE 279-1971, in regard to single failure criteria and testing provisions. By letter dated December 21, 1976 to the NRC, additional relays were proposed to meet these requirements. Submit voltage and time setpoints with tolerances (+) of these additional relays.
Also, Reference 1, Staff Position 1, requires a monthly test of the undervoltage protection system. Submit proposed Technical Specification changes of surveillance requirements to comply with Staff Position 1. (Refer to Model Technical Specification Table 4.3-2 of Reference 1.)
-2
Response
The additional relays installed on the 4160 volt buses are CV-7 relays similar to those previously discussed. The setpoints are identical to those specified in response to item 1 above. In view of the fact that this system is a two out of two system, taking one relay out of service for performance of a monthly test significantly increases the probability of a spurious trip of the offsite power system. To avoid this situation, SCE will continue to calibrate and test these relays when the plant is shutdown every refueling outage. This is consistent with the draft technical specifications submitted in Reference 2. As stated in Reference 2, a formal proposed change to the technical specifications will be submitted through our review committees following review by the Regulatory Staff.
Item 4 What are the voltage nameplate ratings of all Class 1E motors?
Response
The voltage nameplate ratings of San Onofre Unit 1 motors are listed in Table 1.
Item 5 Reference 1, Enclosure 1, page 6, paragraph 1. The intent of the NRC staff positions on Degraded Voltage Protection of the Emergency Power Systems is that under a degraded voltage condition on the Class 1E buses, the buses be disconnected from the preferred source, the loads be shed, the diesel generators started, and the Class 1E buses energized automatically with or without a safety injection signal.
This is in line with Reference 3, Section 4.1 and 4.6, which states that the protection system shall "automatically initiate" protection action and "shall go to completion."
Describe your compliance.
Response
As indicated in Reference 2, in the event of a loss of offsite power coincident with a LOCA, the buses are disconnected from the offsite power system, the loads shed, the diesel generators started, the buses energized and all safety-related loads are automatically connected by the sequencer. In the event of a loss of offsite power without a coincident LOCA, the buses are disconnected from the offsite power system, the loads shed and the diesel generators started; however, the buses are not automatically energized nor are the loads automatically connected. This gives the plant operator the opportunity to take the optimum action to ensure the continued safety of the plant. In the event of just a loss of offsite power, energizing the buses is not required immediately since the plant is in a stable condition.
It will take 30 minutes before the steam generators dry out assuming there is no addition of feedwater during this time. In reality, the turbine driven auxiliary feedwater pump, which is independent of ac power, would
-3 automatically start and deliver feedwater to the steam generators within three minutes. The combination of steam generator dryout time and automatic start of the turbine driven auxiliary feedwater pump provides sufficient time for the operator to determine whether offsite power is available, to then energize the buses and to manually connect the required loads. In most cases it will be preferable to energize the buses from an offsite source if it is available rather than the diesel generators. However, since the diesel generators will be automatically started, they can be connected to the buses at any time during the event. In this way, the operator is permitted to first determine whether the preferred source is available, and if not to go immediately to the emergency source. The time required to make this determination is considerably less than the time available based on the steam generator dryout time.
-4 TABLE 1 VOLTAGE NAME PLATE RATING OF SAN ONOFRE UNIT 1 MOTORS VOLTAGE NAME LOCATION MOTOR DESCRIPTION HORSEPOWER PLATE RATING 1C Charging Pump B (South) 600 4160 IC Safety Injection Pump B (West) 700 4160 iC Feedwater Pump B (West) 3500 4160 2C Feedwater Pump A (East) 3500 4160 2C Safety Injection Pump A (East) 700 4160 2C Charging Pump A (North) 600 4160 480 V Recirculating Pump A (East) 108 440 SWGR No. 1 480 V Salt Water Cooling Pump A (North) 100 480 SWGR No. 1 480 V Refueling Water Pump G27 (North) 150 440 SWGR No. 1 480 V Component Cooling Pump A (North) 125 440 SWGR No. 1 480 V Residual Heat Removal Pump A (East) 75 440 SWGR No. 1 480 V Aux. Salt Water Cooling Pump 150 440 SWGR No. 3 480 V Aux. Feedwater Pump 200 440 SWGR No. 3 480 V Comp. Cooling Pump C (South) 100 440 SWGR No. 3 480 V Recirculating Pump B (West) 108 kVA 440 SWGR No. 2 480 V Salt Water Cooling Pump B (South) 100 480 SWGR No. 2 480 V Refueling Water Pum" G27S (South) 150 440 SWGR No. 2 480 V Component Cooling Pump B (Center) 125 440 SWGR No. 2 480 V Residual Heat Removal Pump B (West) 76 440 SWGR No. 2 MCC-1 Control Room Heat Pump A31 59 440 FRONT MCC-1 Feedwater Pump Lube Oil Pump G3B (West)
.75 208/220/440 FRONT MCC-1 Control Room Supply Fan A33 2
208/220/440 FRONT MCC-1 Boric Acid Transfer Pump G9A (North) 10 kVA 440 FRO0NT
-5 VOLTAGE NAME LOCATION MOTOR DESCRIPTION HORSEPOWER PLATE RATING MCC-1 MOV LCV 1100B Recirculation to
.7 220/440 FRONT Charging Pumps MCC-1 MOV-822A Residual Heat Exchanger Inlet
.5 220/440 REAR MCC-1 MOV-813 Residual Heat Rem. Loop C REAR Hot Leg 1.6 220/440 MCC-1 MOV-883 Residual Heat Rem. Loop A
.5 220/440 REAR Cold Leg MCC-1 MOV-850B Safety Injection to Loop B 1.6 220/440 REAR MCC-1 MOV-866A Safety Injection Recirc. Pump
.166 220/440 REAR MCC-1 Component Cooling Discharge MOV 720B
.3 220/440 REAR MCC-1 MOV-356 Safety Injection Recirculation
.66 230/460 REAR To Loop A MCC-1 Hydrazine Add. Pump G200A 1
440 REAR MCC-1A Feedwater Pump G3B L.O. Cooling 1
230/460 Fan Motor A17B MCC-2 Feedwater Pump Lube Oil Pump G3A (East)
.25 208/220/440 FRONT MCC-2 Spent Fuel Pit Pump G5 50 440 FRONT MCC-2 MOV-357 Safety Injection Recircula FRONT tion to Loop B
.66 230/460 MCC-2 MOV-880 Crosstie From Refueling REAR Water Pump
.67 440 MCC-2 MOV-822B Residual Heat Exchanger Inlet
.5 220/440 REAR MCC-2 MOV-814 Residual Heat Rem. Loop C REAR Hot Leg 1.6 220/440 MCC-2 MOV-834 Residual Heat Rem. Loop A REAR Cold Leg
.5 220/440 MCC-2 MOV-850A Safety Injection to Loop A 1
220/440 REAR MCC-2 MOV-866B Safety Injection Recirc.
REAR Pump Isolation Valve
.166 220/440 MCC-2 Feedwater Pump G3A L.O. Cooling 1
230/460 REAR Fan A17A MCC-2 MOV-720A Component Cooling Discharge
.3 220/440 REAR MCC-2A Test Pump G42 50 440 MCC-2A MOV-LCV-1100C Volume Control Tank Discharge
.7 220/440 MCC-2A Hydrazine Add. Pump G200B 1
440 MCC-3 Boric Acid Injection Pump G12 5 kVA 440 FRONT
-6 VOLTAGE NAME LOCATION MOTOR DESCRIPTION HORSEPOWER PLATE RATING MCC-3 MOV-LCV-1100D Recirc. To Charging REAR Pumps
.7 220/440 MCC-3 UPS MOV-850C Feeder 1.6 480 REAR MCC-3 MOV-358 Safety Injection Recirc. to REAR Loop C
.66 230/460 MCC-3 MOV-883 Refueling Water Tank
.166 460 REAR Isolation Valve DG 1 Jacket Water Pump G-22 1.5 460 MCC #18 DG 1 (Standby) Lube Oil Pump G-69 100 460 MCC #18 DG 1 Jacket Water Radiator Fan A-13A 30 460 MCC #18 DG 1 Jacket Water Radiator Fan A-138 30 460 MCC #18 DG 1 Jacket Water Radiator Fan A-13C 30 460 MCC #18 DG 1 Jacket Water Radiator Fan A-13D 30 460 MCC #18 DG 1 Lube Oil Pump G71 5
460 MCC #18 DG 1 Diesel Fuel Oil Transfer Pump G-74B 2
460 MCC #18 DG 1 Diesel Fuel Oil Transfer Pump G-74A 2
460 MCC #18 DG 1 Emergency Ventilation Fan EF-1A 25 460 MCC #18 DG 1 Emergency Ventilation Fan EF-1B 25 460 MCC #18 DG 1 Emergency Ventilation Fan EF-1C 25 460 MCC #18 DG 1 Normal/Emergency Ventilation Fan EF-1D 30 460 MCC #18
ENCLOSURE 2 Response to NRC Questions Concerning Adequacy of Station Electric Distribution System Voltages San Onofre Unit 1 Reference 1:
NRC letter from W. Gammill to all power licensees, dated August 8, 1979 Reference 2:
SCE letter from K. P. Baskin to D. L. Ziemann, dated May 1, 1980 Reference 3:
SCE letter from W. C. Moody to D. M. Crutchfield, dated May 27, 1981 Item 1 Reference 1, page 2, paragraph 3, requests that a description of the test method used to verify the voltage analyses be submitted. Reference 2 did not provide this test description. Submit a detailed description of the test method used to verify the voltage analyses. The test results can be submitted at a later date.
The test should be conducted when the Class 1E buses are at least 40% loaded.
Response
A detailed description of the test method which will be used to verify the voltage analyses is provided in the attached Appendix No. 1, "Criteria For Testing The SONGS 1 Auxiliary Power System."
As indicated in Reference 3, this test will be conducted during the station outage planned for six effective full power months from the plant startup on June 17, 1981.
Item 2 Do the low voltage AC (less than 480 volts) Class 1E buses supply any instruments or control circuits required by GDC-13? If so, provide terminal voltages to demonstrate that all low-voltage AC Class 1E equipment will be operating within their required voltage ratings for each case analyzed.
Response
Instrument and control circuits are supplied from 120 V AC Vital Buses Nos. 1 through 6 and 3A. All safety-related equipment served by these buses will be operating within their required voltage ratings because the sources of these buses are designed to be maintained within the following limits:
Buses 1 to 4 and 3A Buses 5 and 6
- 1. Voltage 120 V + 2%
120 V + 2%
- 2. Frequency 60 cycles + 1%
60 cycles + 1%
- 3. Harmonic Distortion, Max.
3-1/2%
5%
- 4. Transient 25 milliseconds 20 milliseconds
-2 During normal operation, Vital Buses 1, 2, 3, 3A, 5, and 6 are each fed from their respective inverter set energized from the station battery system.
Vital Bus 4 is fed from the utility bus through a voltage regulator.
Item 3 Per Guidelines 3 and 9 (Reference 1), confirm that the undervoltage protection relays (first and second levels) and the Class 1E motor starter contactors will not drop out when the largest non-Class 1E load starts and reaches steady state while the Class 1E buses are fully loaded for the worst case conditions analyzed.
Response
The largest non-safety related load is a 4000-hp reactor coolant pump. These pumps operate simultaneously during normal operation. During startup operation, these pumps are started, manually, one at time.
To allow startup operation, the undervoltage protection relays (first and second levels) and the safety related motor starter contactors are set such that spurious tripping will not occur when the reactor coolant pumps start and reach-steady state.
This has been confirmed by the actual operation of the plant since 1968, and by voltage calculations conducted for a more severe case. The purpose of these calculations was to verify that all SONGS 1 emergency loads, required for the worst case loss of coolant accident event could be started simultaneously. Under this case, two 700-hp safety injection pumps are started simultaneously with two 3,500-hp feedwater pumps, during the following conditions:
(1) plant in hot shutdwon operation, (2) worst possible grid voltage (217.8 kV).
The resulting voltage dips, on the 4.16 kV buses, and the 480 V buses, do not actuate the undervoltage protection relays and cause dropping out of safety related motor starter contactors.
Item 4 Reference 2, enclosure 1, page 7, states that when the grid is at the maximum expected value of 234.5 kV, system voltage is 102% of the transformer rating of 230 kV at San Onofre Unit 1. Submit the calculated terminal voltages on all Class 1E equipment when the grid is at 234.5 kV (maximum expected) and minimum plant loading.
Response
The maximum grid voltage occurs at the San Onofre 230 kV bus when all three units are on line with their respective generators operating at 105% of the rated generator terminal voltages. Under the above conditions, the maximum grid voltage was found to be 234.5 kV.
-3 During the startup from the recent plant outage, the tap setting of auxiliary transformer C was changed from 230/4.36 kV to 218.5/4.36 kV and the tap settings of station service transformers 1, 2 and 3 were changed from 4.26/0.48 kV to 4.16/0.48 kV.
As a result of these changes, the auxiliary bus voltages are calculated to be higher than considered in Reference 2. Based on the above conditions (i.e., 234.5 kV grid voltage and Units 1, 2 and 3 on line) and the minimum plant operating load of about 14,500 kVA (total loading on Auxiliary Transformer C) the following San Onofre Unit 1 auxiliary bus voltages have been calculated.
o 4 kV buses 4565 V or 109.7% of the rated motor nameplate voltage (4160 V) o 480 V buses 521 V or 118.3% of the rated motor nameplate voltage (440 V)
The bus voltages were given instead of the motor terminal voltage because for the 4 kV and 480 V cases, the shortest motor feeder cable (worst case) was less than 50 feet in length. Since the voltage drop on a 50 foot cable will be less than 1%, the worst case motor terminal voltage will be approximately equal to the bus voltage.
Although the 480 V bus voltage is calculated to be greater than 10% of the rated motor nameplate voltage, this is not considered significant at this time since this assumed that not only Unit 1 is on line, but also Units 2 and 3 which are still under construction. Under the present operating conditions, until Units 2 and 3 are put into service, the actual grid voltage with Unit 1 operating is 224 kV. The resulting calculated 480 V bus voltages are reduced from the above 118.3% to 111% for switchgears 1 and 2, and 112% for switchgear 3. The actual 480 V bus voltages with Unit 1 operating and a grid voltage of 224 kV measured on June 22, 1981 at 9:15 a.m., were 110.5% on switchgears 1 and 2 and 111% on switchgear 3. These values are acceptable.
It is our intention to review the assumptions of our calculations of maximum grid voltages with all three units on line and to optimize the tap settings of auxiliary transformer C and Service Transformers 1, 2, and 3. The results of this further review will be provided by October 30, 1981.
Item 5 Submit the lowest calculated Class 1E load terminal voltages (all Class 1E voltage levels) in the LOCA and unit trip voltage analyses for both motor starting and steady state conditions (Reference 1, Guideline 7).
Response
In response to the NRC's August 8, 1979 letter, a study of the SONGS 1 Auxiliary Power System was made to determine its adequacy for the worst case LOCA event.
In this study, it was postulated that the unit was in the hot shutdown mode, the grid voltage was down to 217.8 kV (minimum calculated grid voltage), and the emergency diesel generators were not available. In response to the LOCA, it was postulated that two safety injection pumps and two feedwater pumps start simultaneously. Calculations were made using the above assumption to determine the maximum voltage dip (on motor starting) and the steady state voltages (after the motors had started and were up to speed) on the SONGS 1 auxiliary buses.
-4 Based on the above results, typical worst case motor terminal voltages (i.e.,
largest motor connected to a bus with longest feeder cable) were calculated for the maximum voltage dip and steady state cases. The results are as follows:
Voltage Dip Steady State Motor Minimum
% of Minimum
% of Voltage Nameplate Motor Term.
Motor Motor Term.
Motor Level Voltage Voltage Nameplate Voltage Nameplate 4 kV buses 4160 V 3589 V 86.3%
4196 V 100.9%
480 V buses 440 V 350.2 V 79..6%
470.7 V 107.0%
These calculations are based on a tap setting of 218,500/4360/4360 volts on auxilary transformer C and settings of 4160/480 volts on station service transformers 1, 2 and 3. As indicated in Item 4 above, these tap settings were changed during the recent startup, and therefore, these calculations indicate bus voltages higher than provided in Reference 2. The 120 VAC buses were not analyzed since they are fed from fully regulated sources as described in response to Item 2 above.
Southern California Edison Company P0
. BOX 800 2244 WALNUT GROVE AVENUE ROSEMEAD. CALIFORNIA 91770 W. C. MOODY TELEPHONES MANAGER, NUCLEAR LICENSING August 19, 1981 (213) 5721817 (2 13) 5 72 -180 6 Director, Office of Nuclear Reactor Regulation 14 Attention:
D. M. Crutchfield, Chief ty/'
Operating.Reactors Branch No.
5 L
Division of Licensing 831 U. S. Nuclear Regulatory Commission Us. KJO.!AR Washington, D.C.
20555 Gentlemen:
Subject:
Degraded Grid Voltage and Adequacy of Station Electrical Distribution System Voltages San Onofre Nuclear Generating Station Unit 1 Your letter of March 24, 1981, requested information for your review of the subject generic issues.
Our response to your request is provided in Enclosures 1 and 2 of this letter. As discussed with your staff, submittal of this information has been delayed due to a change in the tap setting of the station transformers.
If you have any questions on this information, please let us know.
Very truly yours, Enclosures SEP 0 9 1981W 8108240222 810819 PDR ADOCK 05000206 P
Appendix No. I CRITERIA FOR TESTING THE SONGS 1 AUXILIARY POWER SYSTEM 1.0 Purpose 1.1 The purpose of this test is to verify that the SONGS 1 Auxiliary Power System has the capability to simultaneously start and operate all of the emergency loads required for the worst case LOCA event.
1.2 The results of this test will be used to verify that the SONGS 1 Auxiliary Power System has the capability to start and operate all of the emergency loads for the worst postulated grid voltage (217.8 WV).
1.3 It is assumed for the purposes of this test that the emergency diesel generators are not available.
2.0 Scope 2.1 Determine the steady state voltage on the grid and SONGS 1 auxiliary power system prior to initiation of the test.
2.2 Determine the voltage dip associated with simultaneously starting of the emergency loads required for the worst case LOCA event.
2.3 Determine the steady state voltage of the auxiliary power system with the emergency loads operating for the worst case LOCA event.
3.0 Plant conditions required to simulate the worst case LOCA event.
3.1 Electrical Requirements 3.1.1 Breaker Alignments 3.1.1.1 4.16 kV buses 3.1.1.1.1 4.16 kV bus "lA" shall be fed from Aux.
Transformer "A".
Bus tie breakers between 4.16 kV buses "lA" and "1C" shall be open.
3.1.1.1.2 4.16 kV bus "1B" shall be fed from Aux.
Transformer "B".
Bus tie breakers between 4.16 kV buses "1B" and "2C" shall be open.
3.1.1.1.3 4.16 kV buses "1C" and "2C" shall be fed from Aux. Transformer "C".
-2 3.1.1.2 480 V buses 3.1.1.2.1 480 V Switchgear No. 1 shall be fed from 4.16 kV bus "1C."
3.1.1.2.2 480 V switchgear No. 2 and No. 3 shall be fed from 4.16 kV bus 2C.
3.1.2 Electrical Loads 3.1.2.1 The following loads (or loads of equivalent horsepower) are required to be in operation (to simulate the hot shutdown mode) prior to the starting of the emergency loads.
4.16 kV Bus "1C" Circulating Water Pump "B" Condensate Pump "D" Charging Pump "B" Turbine Plant Cooling Water Pump G65.
4.16 kV Bus "2C" -
Circulating Water Pump "A" 480 Switchgear 1:
Press Htr. Control Group "A" Instr. Air Compressor "A" SEB fan No. A-40 SEB Fan No. A-42 MCC -
1A All miscellaneous MCC -
1 loads required MCC -
1B during hot shutdown 480 Switchgear 2:
Press Htr. Control group "B" SEB Fan No. A-41 SEB Fan No. A-43 MCC -
2B All miscellaneous MCC - 2 loads required MCC -
2A during hot shutdown 480 Switchgear 3:
Auxiliary Feedwater Pump Boric Acid Batching Heater Turbine Auxiliary Lube Oil Pump All miscellaneous MCC -
3 loads required during hot shutdown 3.1.2.2 The following emergency loads must be operable prior to the initiation of the test.
4.16 kV Bus "C" Feedwater Pump "B" Safety Injection Pump "B" 4.16 kV Bus "2C" Feedwater Pump "A" Safety Injection Pump "A"
-3 480 V Switchgear #1 *Refueling Water Pump "A" Salt Water Cooling Pump "A" Component Cooling Pump "A" 480 V Switchgear #2 *Refueling Water Pump "B" The following loads may be substituted for the Refueling Water Pumps.
480 V Switchgear #2 Salt Water Coolng Pump "B" Component Cooling Pump "B" 480 V Switchgear #3 Component Cooling Pump "C" 3.2 Mechanical Requirements 3.2.1. Mechanical equipment will be operated during the test for the purpose of simulating electrical loads only (mechanical equipment includes pumps, fans.and air compressors).
3.2.2 Mechanical equipment shall be operated within its limits.
3.2.3 Centrifugal pumps shall have adequate NPSH.
3.2.4 Centrifugal pumps may be operated at minimum flow conditions, but shall not be operated below minimum flow conditions.
3.2.5 Centrifugal pumps shall not be operated beyond their design flow, unless an evaluation has been performed that shows that the pump will operate satisfactorily and manufacturer's concurrence has been obtained.
3.2.6 The Station Watch Engineer shall be responsible for aligning the plant such that the loads required for simulation of the hot shutdown and LOCA modes can be operated.
3.3 Starting of the required emergency loads.
3.3.1 The required emergency loads will be started by the sequencer.
3.3.1.1 The test will be initiated by the SIS test buttons located in the control room.
3.3.2 Any load initiated by the sequencer but not required for the test will be disabled.
3.3.3 The sequencer external wiring shall be modified such that any equipment protection devices disabled by the seqencer will remain in operation.
-4 3.4 Instrumentation Requirements 3.4.1 The following parameters will be measured.
3.4.1.1 Voltage Dip:
4.16 kV buses "1C" and "2C;" 480 V Switchgear No. 1, 2 and 3.
3.4.1.2 Steady State Voltages:
230 kV East and West buses; 4.16 kV buses "1C" and "2C"; 480 V Switchgear No. 1, 2 and 3.
3.4.1.3 Currents on the X
and Y
windings of Aux.
Transformer "C".
3.4.1.4 Instrumentation will be supplied and installed by the SCE Apparatus Group and the Station.
4.0 Test Procedures 4.1 Start all loads required to be in operation prior to initiation of test.
4.1.1 Note condition of grid (i.e., list lines in service to SONGS 230 kV bus) 4.1.2 Record steady state voltages on the following:
4.16 kV buses "1C" and "2C" 480 V Switchgear No. 1, 2, and 3 230 kV East and West buses 4.2 Initiate starting of emergency loads by depressing SIS buttons in the control room.
4.2.1 Record the voltage dip on the following:
4.16 kV buses "1C" and "2C" 480 V Switchgear No. 1, 2, and 3 4.2.2 Verify that emergency loads have started and are operating.
4.2.3 Record the steady state voltages on the following buses with the emergency loads operating.
230 1V East and West buses 4.16 kV buses "1C" and "2C" 480 V Switchgears No. 1, 2, and 3 9
5.0 Acceptance Criteria 5.1 Voltage Dip does not exceed 20% of the motor nameplate voltage.
5.2 Emergency loads start and operate normally.
5.3 The steady state voltage shall be greater than or equal to 90% of the motor nameplate voltage.