ML17192A680

Secondary Procedure Dgp 2-3, Revision 5, Unit 2 & 3 Reactor Scram.

ML17192A680
Person / Time
Site:	Dresden
Issue date:	01/05/1980
From:	COMMONWEALTH EDISON CO.
To:
Shared Package
ML17192A611	List: ML17192A610 ML17192A671 ML17192A672 ML17192A673 ML17192A674 ML17192A675 ML17192A676 ML17192A677 ML17192A678 ML17192A679 ML17192A680 ML17192A681 ML17192A682 ML19323A953
References
DGP-2-3, NUDOCS 8005080528
Download: ML17192A680 (3)

Text

SO 05.t.i 8 O~~fs'DGP 2-3 .* ,

I .f ~~ 2/3 ~~~OR SCRAM

. e*-. .. '. ** Revision 5 January 1980

• • • • • • -*-****-*A. PURPOSE To outline the procedure used to shutdown the reactor when an

• emergency requires a manual scram to prevent exceeding a safety limit or damage to plant equipment. The same steps are taken following an automatic scram.

B. REFERENCES DGP 2-1, Normal Unit Shutdown.

C. PREREQUISITES

1. An automatic reactor scram has occurred or

2. During plant operation the operator has recognized the need to implement this procedure.

3. If time is available before manually scramming the reactor, perform the following:

a. Reduce power with recirculation flow.

b. TRANSFER aux. power to Transformer 22(32)

c. START the Main Shaft Suction Pump and Emergency Bearing Oil Pump.

d. RAISE water level to the High Level Alarm point.

D. PROCEDURE NOTE The first six actions should be performed as Immediate Act'ions on every scram. The remaining actions should be performed as Immediate Actions where specified by abnormal procedures or in conjunction with the Subsequent Actions of abnormal procedures.

1. PRESS both scram buttons if it is desired to manually scram the Rx.

• A**p-* ri:r9n tr :*i\

\'f1:"1"'!\

V\V~

1 of 3 t.~ 1~:0579 g:O.S.R,

Revision 5

. ' I f *e

(_, 2. PLACE the Rx Mode Switc;h to SHurDOWN or REFUEL.

• 3.:******CHECK***to**see-if all**control-rods. are .fully inserted.

'NOTE This can be done via an inspection of the full core display or computer output; or by placing the Mode Switch to REFUEL and verifying that the Refuel One Rod Permissive Light is ON. If the light is OFF CHECK the full core di.~play and INSERT any drives not already at 00. No'tify the Shift Engineer.

4. VERIFY APRM readings decreasing or downscale.

I

5. Maintain feedwater in .AUTO unless controller failure occurs. Control level* between +20 and +40 inches by observing more than one available indication.

NOTE On a scram, the automatic Feed Control System will reduce the c:ontrolling setpoint by 1/2.

If the Feed Contr.ol System is in AUTO, the setpoint will return to its original level when the scram is reset.

6.

• VERIFY turbine and generator have TRIPPED.

7. If necessary, STOP feed pumps to prevent excessive reactor level. Verify, if possible, that more than one type of level indication has Hi Level before stopping feed pumps.

8. VERIFY auxiliary power has transferred to the re-serve auxiliary transformer.

9. INSERT SRM and !RM Detectors. Maintain IRM on scale to monitor shutdown.

10. VERIFY Main Shaft Suc~ion Pump AUTO STARTED.

11. The Generator Trip also trips Stator Cooling Pumps.

RESET 86 relay to start Stator Cooling Pumps.

12. Limit the cooldown rate to 100°F/hr. In an emer-gency, a 240° step change may be used. Do not exceed the 140° AT limit between reactor vessel and flange *

. rrn

_.!:*~.

2 of 3

.,. **~-:. *. . * .. , Revision 5  :. .... ~ ' . .. ,.

(-

l 13. MONITOR the Reactor Safety Systems such.as isola-tion condenser, auto depressurization, LPCI operation,

• *-*isola*tion**va1ves, *etc *... Operate manually, if required, to prevent potential injury to personnel, potential off-site releases above Technical Specification limits, or damage to equipment.

14. Maintain vacuum in the main condenser with the SJAE, and bypass steam to cool down and depressurize the system, if cooldown is required.

15. If it becomes necessary to raise reactor water level, do so very slowly to ~nimize thermal shock on the system.

16. CHECK control room panels to verify all systems are operating properly. Continue the cooldown, if required, following the Normal Unit Shutdown procedure (DGP 2-1).

17. Complete Control Room Log Book .entries.

18. Complete Scram Report Data Sheet (DGP 2-3-Sl).

NOTE The blanks beside each step is an operator convenience. If the operator desires to use this procedure as a checklist to ensure all necessary actions are accomplished he may do so. However, this procedure is not a checklist and need not be treated as such.

r *- -

l\iQ r\ r, -;,:*. \ '/~

~~: *'1 * \ -** :*~.~

3 of 3 (FINAU

. -.r