ML20211G676

Proposed Tech Specs Revising Table 3.3.3-2 Re 4.16 Kv Emergency Bus Undervoltage Relays

ML20211G676
Person / Time
Site:	Hope Creek
Issue date:	02/17/1987
From:	Public Service Enterprise Group
To:
Shared Package
ML20211G666	List: ML20211G661 ML20211G676
References
NUDOCS 8702250486
Download: ML20211G676 (3)

Text

~

ATTACHMENT 1 PROPOSED CHANGE TO TECHNICAL SPECIFICATIONS LCR 87-01 HOPE CREEK GENERATING STATION Page 1 of 2 DOCKET NO. 50-354 Description of Change Revise Technical Specification Table 3.3.3-2 to change the description of the 4.16 kv Emergency Bus Undervoltage (Degraded Voltage) relays. The four inverse time delay voltage relays will be replaced with four solid state voltage relays pending approval of this request.

In addition, an editorial change is provided to change the footnote for the undervoltage trip setpoints and allowable values. The footnote currently states that the voltages shown are the maximum that will not result in a trip. Actually, since the relays are undervoltage relays, the voltages are the minimum that will not result in a trip.

Reason for Change The inverse time delay voltage relay currently used tends to exceed the permissible time of 20 + 15, -5 seconds at 109.0 volts specified in Technical Specification Table 3.3.3-2, Trip Function 5.b.b. To prevent this from occurring, PSE&G has increased the surveillance frequency of these relays in order to compensate for recurring setpoint drif t.

In addition to exceeding the permissible time value, the inverse time delay relays remain energized once they are tripped due to undervoltage. A solid state relay used in conjunction with an associated time delay relay (Agastat type E7012PD) will eliminate the reset requirement imposed by the inverse time delay relay.

The undervoltage protection schemes will be revised such that in i the event of complete loss of voltage (70% or less of normal i voltage), the undervoltage relay will trip the incoming feeder breaker without a time delay. For the degraded voltage case, the time delay will be controlled by the Agastat time delay relays which will operate within the tolerance specified in Technical l Specification Table 3.3.3-2, 1

The change of the word " maximum" to " minimum" in Table 3.3.3-2 is being submitted as an editorial correction. Since the footnote refers to the undervoltage relays, the trip setpoints and allowable values are in fact the minimum voltages that will not result in a trip. If the voltage decreases beyond the minimum, an undervoltage trip is initiated. This change is editorial since it does not involve any change in system operation or configuration, but merely revises the footnote to state what was originally intended.

070223Qk[3h45 PDH A PDR P

l 4

LCR 87-01 1 Page 2 of 2 2

Significant Hazards Consideration This proposed change to the Hope Creek Generating Station '

Technical Specifications does not:

a) involve a significant increase in the probability or consequences of an accident previously evaluated. The inverse time delay voltage relays will be replaced with single phase solid state voltage relays. All components involved in the modification will be qualified to Class 1E standards. Since the revised configuration will operate within the parameters specified in Technical Specification Table 3.3.3-2 (i.e. 20 + 15, - 5 seconds at 109.0 volts),

the system's reliability will be increased.

b) create the possibility of a new or different kind of accident from any accident previously evaluated. Since the proposed modification will perform the same function as the inverse time delay voltage relays currently in place, ard is of higher reliability, the possibility of a new or different kind of accident is not created.

c) involve a significant reduction in a margin of safety.

The same Technical Specification requirements will be imposed on the solid state relays as are currently imposed on the inverse time delay voltage relays. Therefore, the margin of safety is not reduced.

Based on the above evdluation, PSE&G has determined that this proposed change does not involve a significant hazards cc' sideration.

i l

I l

-e. -e-- -. - - - _-.,w----r- --,-------s---.---.% -y--> - ---.p-+

9 1ABLE 3.3.3-2 (Continued) 5 EMERGENCY CORE COOLING SYSTEM ACTUATION INSTRUMENTATION SETPOINTS g

c) ALLOWABLE TRIP FUNCTION TRIP SETPOINT VALUE

4. AUTOMATIC DEPRESSURIZATION SYSTEM

a. Reactor Water Level - Low Low Low, Level 1 >-129 inches * >-136 inches

b. Drywell Pressure - High 51.68psig i1.88psig

c. ADS Timer < 105 seconds < 117 seconds

d. Core Spray Pump Discharge Pressure - High 145 psig 5155psig

- > 125 psig

e. RHR LPCI Mode Pump Discharge Pressure-High 125 psig i135psig

> 115 psig

f. Reactor Vessel Water Level-Low, level 3 > 12.5 inches i 11.0 inches

g. ADS Drywell Pressure Bypass Timer 35.0 minutes 35.5 minutes

h. ADS Manual Inhibit Switch NA NA

i. Manual Initiation NA NA ,

, 5. LOSS OF POWER s s

• 4.16 kv' Emergency Bus Undervoltage a. 4.16 kv Basis - :r a.

Y (Loss of Voltage) 2975 1 30 volts 2975 1 63 volts  !=

D b. 120 v Basis - "

85 1 0.85 volts 85 i 1.8 volts w

b. 4.16 kv Emergency Bus Undervoltage a. 4.16 kv Basis -

> (Degraded Voltage)** > 3857 volts -> 3857 volts

b. 120 v Basis -

> 110.2 volts > 109.0 volts

c. 20 sec @ 20 + 15, - 5 sec 109.0 volts @ 109.0 volts

• See Bases Figure B 3/4 3-1. / /

• • This is c "re n e t o t hj voltage relay. The voltages shown are thelma*+euelothat will not result in a trip. Some voltage conditions will result in decreased trip times.

!a solid state l l minimum]

,