ML17263A254
| ML17263A254 | |
| Person / Time | |
|---|---|
| Site: | Ginna  |
| Issue date: | 04/21/1993 |
| From: | Marlow T ROCHESTER GAS & ELECTRIC CORP. |
| To: | |
| Shared Package | |
| ML17263A255 | List: |
| References | |
| AP-TURB.2, NUDOCS 9305140008 | |
| Download: ML17263A254 (11) | |
Text
EOP:
P-TURB-2 T!TLE:
TURBINE LOAD REJECTION REV ll PAGE 1 of 10 ROCHESTER GAS AND ELECTRIC CORPORATION GINNA STATION CONTROLLED COPY NUMBER TECHNICAL REVIEW PORC REVIEW DATE PLANT SUPERINTENDENT EFFECTIVE DATE CATEGORY 1.0 REVIEWED BY:
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P-TURB.2 TURBINE LOAD REJECTION REV:
11 PAGE 2 of 10 A.
PURPOSE - This procedure provides the guidance necessary to control the plant during a transient resulting from an unanticipated turbine/secondary plant load decrease.
B.
ENTRY CONDITIONS/SYMPTOMS 1.
SYMPTOMS The symptoms of TURBINE LOAD REJECTION are; a.
Annunciator F-30, OPaT TURBINE RUNBACK, lit, or b.
Annunciator F-31, OTaT TURBINE RUNBACK, lit, or c.
Unexplained decrease in main generator output.
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P-TURB.2 TITLE:
TURBINE LOAD REJECTION REV 11 PAGE 3 of 10 STEP ACTION/EXPECTED RESPONSE
RESPONSE
NOT OBTAINED CAUTION o
IF, AT ANY TIME DURING THIS PROCEDURE, A REACTOR TRIP OR SI OCCURS, E-O, REACTOR TRIP OR SAFETY INJECTION, SHALL BE PERFORMED.
o ANY hT RUNBACK SIGNAL WILL BLOCK AUTO AND MANUAL OUT MOTION OF ROD CONTROL SYSTEM.
1 Check Rod Control:
o ROD CONTROL BANK SELECTOR switch in AUTO a.
Ensure ROD CONTROL BANK SELECTOR switch in MANUAL.
o Control rods stepping 'in as required
- b. Insert control rods as necessary to restore Tavg to Tref.
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P-TURB.2 TITLE:
TURBINE LOAD REJECTION REV 11 PAGE 4 of 10 STEP ACTION/EXPECTED RESPONSE
RESPONSE
NOT OBTAINED 2
Check Steam Dump Status:
- a. Annunciator F-15, RCS TAVG DEV, EXTINGUISHED a.
Perform the following:
- 1) Place STEAM DUMP MODE SELECTOR Switch to MANUAL.
b.
Steam dump armed and operating:
o Annunciator G-15, STEAM DUMP ARMED - LIT o
Steam dump operating to restore Tavg to within 6'F of Tref
- 2) Place steam dump controller, HC-484, to MANUAL.
3 ) Operate steam dump valves manually as necessary.
4)
Go to Step 3.
- b. IF steam dump required but NOT I
operating, THEN perform the following:
- 1) Place STEAM DUMP MODE SELECTOR Switch to MANUAL.
- 2) Place steam dump controller, HC-484, to MANUAL.
C
- 3) Operate steam dump valves manually as necessary.
3 Verify Tavg TRENDING TO TREF Place ROD CONTROL BANK SELECTOR switch to MANUAL and insert control rods as necessary to restore Tavg to Tref.
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P-TURB.2 TITLE:
TURBINE LOAD REJECTION REV:
11 PAGE 5 of 10 STEP ACTION/EXPECTED RESPONSE
RESPONSE
NOT OBTAINED 4
Check Turbine Runback Criteria:
a.
Any AT annunciator
- LIT
[
a.
Go to Step 7.
~ F-30, OPBT TURBINE RUNBACK
~ F-31, OTBT TURBINE RUNBACK b.
AT runback occurring as required
- b. Place EH in MANUAL and reduce turbine load as necessary.
5 Evaluate AT Channels For Instrument Failure:
- a. Perform AT indication channel checks
- ALL CHANNELS APPROXIMATELY EQUAL
~ 4 AT channels
~ 4 OPAT setpoints
~ 4 OTAT setpoints
- a. IF channel failure indicated, THEN perform the following:
- 1) Allow runback to continue until condition clears or until reactor power is less than 75%.
- 2) Place EH in manual to terminate runback at 75% if necessary.
- b. Verify all AT channels
- LESS THAN hT SETPOINTS 3)
Go to Step 6.
- b. Verify automatic AT runbacks continuing as necessary.
IF
- NOT, THEN place EH control in MANUAL and reduce turbine load as necessary.
c.
Go to Step 7
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P-TURBe2 TURBINE LOAD REJECTION REV:
11 PAGE 6 of 10 STEP ACTION/EXPECTED RESPONSE
RESPONSE
NOT OBTAINED 6
Determine Cause Of-aT Runback:
a.
Check Instrument Busses
- ALL ENERGIZED
- b. Perform hT runback circuit input channel checks
- ALL CHANNELS APPROXIMATELY EQUAL
~ 4 hT channels
~ 4 Tavg channels
~ 4 PRZR pressure channels
~ 4 Power range EI channels
- a. Continue with Step 7 while attempting to restore failed instrument bus (Refer to T-25, INSTRUMENT AND CONTROL BUS),
- b. IF any 4T, Tavg or PRZR pressure channel has failed, THEN defeat failed channel (Refer to ER-INST.1, REACTOR PROTECTION BISTABLE DEFEAT AFTER INSTRUMENTATION LOOP FAILURE)
IF any 41 channel has failed, THEN defeat failed PR channel (Refer to ER-NIS.3, PR MALFUNCTION)~
7 Check Tur'bine Power - STABLE,! 'Determine cause of continued power reduction and stabilize load if possible.
8 Check Main Generator Load GREATER THAN 15 MW IF load can NOT be stabilized above 15 MW, THEN trip turbine and go to AP-TURB.1, TURBINE TRIP WITHOUT RX TRIP REQUIRED, Step 1.
EOP:
P-TURB.2 T!TLE:
TURBINE LOAD REJECTION REV:
11 PAGE 7 of 10 STEP ACTION/EXPECTED RESPONSE
RESPONSE
NOT OBTAINED CAUTION IF STEAM DUMP CONTINUES FOR A SIGNIFICANT LENGTH OF TIME, CONDENSATE TEMPERATURE AND CONDENSER BACK PRESSURE SHOULD BE MONITORED.
NOTE:
Tavg will indicate high or low for some instrument failures affecting steam dump control, rod control, and PRZR level control.
9 Establish Stable Plant Conditions:
a.
Tavg - TRENDING TO TREF
.b.
PRZR pressure
- TRENDING TO 2235 PSIG
- a. Insert control rods or, if necessary decrease turbine load to match Tavg to Tref.
- b. Verify proper operation of PRZR heaters and spray or take manual control of PRZR pressure controller 431K.
IF pressure can NOT be controlled, THEN refer to AP-PRZR.l, ABNORMAL PRESSURIZER PRESSURE.
c.
PRZR level - TRENDING TO PROGRAM c, Verify proper operation of charging pump speed controllers OR take manual control of speed controllers to control PRZR level.
d.
Steam dump valves CLOSED
- d. Ensure proper operation of steam dump control system.
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P-TURB.2 TURBINE LOAD REJECTION REV:
11 PAGE 8 of 10 STEP ACTION/EXPECTED RESPONSE
RESPONSE
NOT OBTAINED 10 Check REGEN Hx Letdown Indications:
o Annunciator A-4, REGEN HX LETDOWN OUT HI TEMP 395'F-EXTINGUISHED o
REGEN Hx letdown outlet temperature
- STABLE OR DECREASING Adjust charging flow and HCV-142 as necessary to control REGEN Hx letdown outlet temperature.
IF REGEN Hx letdown outlet temperature can NOT be controlled, THEN perform the following:
a.
Close all letdown orifice valves (AOV-200A, AOV-200B and AOV-202).
- b. Close loop B to REGEN Hx isolation valve (AOV-427).
11 Verify Bus 12A And Bus 12B Energized:
o Bus 12A normal or alternate feed breaker CLOSED Go to AP-ELEC.1, LOSS OF 12A AND/OR 12B TRANSFORMER.
o Bus 12B normal or alternate feed breaker CLOSED o
Bus 12A and 12B voltage GREATER THAN 4KV 12 Verify Cause Of Turbine Load Rejection IDENTIFIED Attempt to determine and correct cause of turbine load rejection.
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P-TURB.2 TITLE:
TURBINE LOAD REJECTION REV 11 PAGE 9 of 10 STEP ACTION/EXPECTED RESPONSE
RESPONSE
NOT OBTAINED CAUTION IF AN INSTRUMENT CHANNEL HAS FAILED, THEN RESTORATION OF PLANT CONDITIONS IN THE FOLLOWING STEP MAY NOT BE POSSIBLE UNTIL THE FAILED CHANNEL, IS DEFEATED.
13 Establish Normal Plant Conditions:
- a. Verify EH control in AUTO IMP IN
- a. IF cause of load rejection is corrected, THEN place EH in AUTO IMP IN.
- b. Verify steam dump controller, HC-484, in AUTO at 1005 psig
- c. Verify annunciator G-15, STEAM DUMP ARMED - EXTINGUISHED
- c. IF Tavg within 6'F of Tref, THEN perform the following:
- 1) Ensure steam dump valves closed.
d.
Rod insertion limit alarms EXTINGUISHED e.
NIS PR AI - WITHIN t 5%
OF TARGET VALUE
- 2) Reset steam dump.
- d. IF any AT channel failed, THEN determine actual RIL from Tech Spec figure 3.10-1.
IF alarm
- valid, THEN borate as necessary and withdraw control rods to clear insertion limit alarms (refer to affected rod bank alarm response procedures if necessary).
- e. Borate/dilute to restore hl to within limits.
- f. Verify charging pump speed control in AUTO
- f. Place charging pump speed control in AUTO if desired.
- g. Verify Rod Control Selector Switch in AUTO
- g. Place Rod Control Selector Switch in AUTO if desired.
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P-TURB.2 TURBINE LOAD REJECTION REV'l PAGE 10 of 10 STEP ACTION/EXPECTED RESPONSE
RESPONSE
NOT OBTAINED NOTE:
Refer to 0-9.3, NRC IMMEDIATE NOTIFICATION, for reporting requirements.
14 Notify Higher Supervision 15 Return To Procedure Or Guidance In Effect
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