ML20078A773

Proposed Tech Specs Reflecting Removal of Recirculation Flow Scram

ML20078A773
Person / Time
Site:	Oyster Creek
Issue date:	06/24/1994
From:	GENERAL PUBLIC UTILITIES CORP.
To:
Shared Package
ML20078A767	List: ML20078A764 ML20078A769 ML20078A773
References
NUDOCS 9407010263
Download: ML20078A773 (2)

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1 FUNCTION LIMITING SAFETY SYSTEM SETTINGS K. Reactor Low-Low Water Level, 27'2" above the top of the Core Spray Initiation active fuel L. Reactor Low-Low Water Level, 27'2" above the top of the Isolation Condenser Initiation active Fuel with time delay 53 seconds M. Turbine Trip, Scram 10 percent turbine stop valve (s) closure from full open N. Generator Load Rejection, Initiate upon loss of oil Scram pressure from turbine acceleration relay

0. DELETED P. Loss of Power

1) 4.16 KV Emergency Bus 0 volts with 3 seconds !

Undervoltage (Loss of 0.5 seconds time delay Voltage)

2) 4.16 KV Emergency Bus 3671 1% (36.7) volts Undervoltage (Degraded 10 10% (1.0) second time Voltage) delay Bm es:

Safety limits have been established in Specifications 2.1 and 2.2 to protect the integrity of the fuel cladding and reactor coolant system barriers, respectively.

Automatic protective devices have been provided in the plant design for corrective actions to prevent the safety limits from being exceeded in normal operation or operational transients caused by reasonably expected single operator error or equipment malfunction. This Specification establishes the trip settings for these ,

automatic protection devices. '

The Average Power Range Monitor, APRM*, trip setting has been established to assure never reaching the fuel cladding integrity safety limit. The APRM system responds l to changes in neutron flux. However, near the rated thermal power, the APRM is  ;

calibrated using a plant heat balance, so that the neutron flux that is sensed is j read out as percent of the rated thermal power. For slow maneuvers, such as those I where core thermal power, surface heat flux, and the power transferred to the water follow the neutron flux, the APRM will read reactor thermal power. For fast j transients, the neutron flux will lead the power transferred from the cladding to the water due to the effect of the fuel time constant. Therefore, when the neuron flux increases to the scram setting, the percent increase in heat flux and power j transferred to the water will be less than the percent increase in neutron flux.

The APRM trip setting will be varied automatically with recirculation flow, with the trip setting at the rated flow of 61.0 x 10' lb/hr of greater being 115.7% of rated neutron flux. Based on a complete evaluation of the reactor dynamic performance during normal operation as well as expected maneuvers and the various mechanical failures, it was concluded that sufficient protection OYSTER CREEK 2.3-3 Amendment No. 71, 75, 80 9407010263 940624 PDR ADOCK 05000219 P pon

valves to a load rejection and failure of the turbine bypass system. This scram is initiated by the loss of turbine acceleration relay oil pressure. The timing ,

for this scram is almost identical to the turbine trip. '

l The undervoltage protection system is a 2 out of 3 coincident logic relay system designated to shift emergency buses C and D to on site power should normal power be lost or degraded to an unacceptable level. The trip points and time delay settings have been selected to assure an adequate power source to emergency safeguards systems in the event of a total loss of normal power or degraded t conditions which would adversely affect the functioning of engineered safety r features connected to the plant emergency power distribution system.

References (1) FDSAR, Volume I, Section VII-4.2.4.2 (2) FDSAR, Amendment 28, Item III. A-12 (3) FDSAR, Amendment 32, Question 13 -

(4) Letters, Peter A. Morris, Director, Division of Reaction Licensing, USAEC to John E. Logan, Vice President, Jersey Central Power and Light -

Company, Dated November 22, 1967 and January 9, 1968 (5) FDSAR, Amendment 65, Section B.XI.

(6) FDSAR, Amendment 65, Section B.IX k

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l OYSTER CREEK 2.3-7 Amendment No.: 75, 80 l