ML20202F799

Proposed Tech Specs,Consisting of Proposed Change 19, Incorporating Changes to Station 125/250-volt Dc Battery Surveillance Requirements & Bases,To Improve Demonstration of Unit Battery Sys Operability

ML20202F799
Person / Time
Site:	Cooper
Issue date:	07/03/1986
From:	NEBRASKA PUBLIC POWER DISTRICT
To:
Shared Package
ML20202F753	List: ML20202F748 ML20202F799
References
NUDOCS 8607150235
Download: ML20202F799 (8)

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! LIMITING CONDITIONS FOR OPERATION SURVEILLANCE REOUIREMENTS 3.9.A 4.9.A.2 (cont'd)

During the manthly generator test the diesel generator starting air compres-sor shall be checked for operation and j its ability to recharge air receivers.

The operation of the diesel fuel oil ,

i transfer pumps and fuel oil day tank.

level switches shall be demonstrated, and the diesel starting time to reach rated voltage and frequency shall be l' li

, logged.

b. Once every 18 months the condition under which the diesel generator is

., required will be simulated and a test conducted to demonstrate that it will start and accept the emergency load within the specified time sequence.

The results shall be logged.

I c. Specification 4.9.A.2.c deleted.

i d. Once a month the quantity of diesel fuel available shall be logged.

I l e. Every three months and upon delivery a sample of diesel fuel shall be checked for quality. The quality shall be j within the acceptable limits specified in Table 1 of ASTM D975-68 for Nos. ID or 2D and logged.

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f. Each diesel generator shall be given j an annual inspection in accordance with instructions based on the manu-

, facturer's recommendations.

3. 125 VDC Unit Batteries  !

a. Every week, the following parameters

' shall be verified. The actual values shall be measured and logged: )

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1. The total battery terminal vol-i tage on float charge is equal to or greater than 125 volts,

2. The electrolyte level of each pilot cell is between the min-

I imum and maximum level indica-tion marks, 8607150235 860703 PDR ADOCK 05000298 l p PDR

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I LIMITING CONDITIONS FOR OPERATION SURVEILLANCE REQUIREMENTS

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-N 3.9.A 4.9. A (cont 'd.)

3. The pilot cell voltage is 2.0V minimum and specific gravity 1190 minimum, corrected for 77*F and

, . electrolyte level.

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b. Every quarter, the following para-i meters shall be verified. The actual values shall be measured and logged:

1. The electrolyte level of each connected cell is between the I minimum and maximum level in-dication marks.

l 2. For each connected cell, the

! voltage is 2.0V minimum and I

specific gravity is 1190 minimum, corrected for 77'F and electrolyte level, B. Operation with Inoperable Equipment 3. The electrolyte temperatures j in a representative sample of l 1. Whenever the reactor is in Run Mode or cells, consisting of at least

! Startup Mode with the reactor not in a every sixth cell, are within Cold Condition, the availability of !5'F.

electric power shall be as specified j in 3.9.A.1, except as specified in c. Once each operating cycle the 125V 2 3.9.B.1. battery charger will be tested to verify that the chcrger can supply

a. Incoming Power 150 Amperes at 125V for four hours.

1. From and after the date incoming power d. Once each operating cycle, the is not available from a startup or emer- battery capacity shall be verified gency transformer, continued reactor to be at least 85% of the manufac-operation is permissible under this turer's rating when subjected to a condition for seven days. At the end performance discharge test.

of this period, provided the second source of incoming power has not been made immediately available, the NRC must be notified of the event and the plan to restore this second source.

During this period, the two diesel generators and associated critical buses must be demonstrated to be operable.

2. From and after the date that incoming power is not available from both start-up and emergency transformers (i.e.,

both failed), continued operation is permissible, provided the two diesel generators and associated critical j buses are demonstrated to be 1

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LIMITING CONDITIONS FOR OPERATION SURVEILLANCE REQUIREMENTS i

3.9.B (cont'd.) 4.9.A.4 250 VDC Unit Batteries operable, all core and containment a. Every week, the following parameters cooling systems are operable, reactor shall be verified. The actual values power level is reduced to 25% of the shall be measured and logged:

rated and NRC is notified within 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> of the situation, the precau- 1. The total battery terminal i tions to be taken during this period voltage on float charge shall be

, and the plans for prompt restora- equal to or greater than 250 volts,

! tion of incoming power.

2. The electrolyte level of each

b. Diesel Generators pilot cell is between the minimum and maximum level

! 1. From and after the date that one of indication marks, t the diesel generators or an associ-

ated critical bus is made or found 3. The pilot cell voltage is 2.0V l to be inoperable for any reason, minimum and specific gravity

continued reactor operation is per- 1190 minimum, corrected to 77'F

{ missible in accordance with Speci- and electrolyte level, fication 3.5.F.1 if Specification 3.9.A.1 is satisfied. b. Every quarter, the following par-I ameters shall be verified. The j 2. From and after the date that both actual values shall be measured

! diesel generators are made or found and logged:

to be inoperable for any reason,

! continued reactor operation is per- 1. The electrolyte level of each l missible only during the succeeding connected cell is between the

! l 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> in accordance with Speci- minimum and maximum level 1 fication 3.5.F.2 if Specification indication marks.

3.9.A.1 is satisified.

2. For each connected cell, the i

j 3. From and after the date that one of voltage is 2.0V minimum and

! the diesel generators or associated specific gravity is 1190 min-  !

critical buses and either the emer- imum, corrected for 77'F and gency or startup transformer power electrolyte level, i source are made or found to be in-operable for any reason, continued 3. The electrolyte temperatures i reactor operation is permissible in in a representative sample of accordance with Specification 3.5.F.1, cells, consisting of at least provided the other off-site source, every sixth cell, are within startup transformer or emergency 5*F.

transformer is available and capable of automatically supplying c. Once each operating cycle, the 250V power to the 4160V critical buses and battery charger will be tested to the NRC is notified within 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> verify that the charger can supply of the occurrence and the plans for 200 amperes at 250 volts for four restoration of the inoperable compo- hours.

nents.

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LYMITING C014DITIONS FOR OPERATION SURVEILLANCE REQUIREMENTS _ _ __ _ __

3.9.B.5 (cont'd.) 4.9. A.4 (cont'd)

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c. DC Power d. Once each operating cycle, the bat-

- tery capacity shall be verified to

1. From and after the date that one of be at least 85% of the manufacturer's the 125 or 250 volt battery systems rating when subjected to a performance is made or found to be inoperable discharge test.

for any reason, continued reactor operation is permissible during the 5. PowerMonitoringSystemforRPSSysteml i succeeding ten days within electri-cal safety considerations, provided The above specified RPS power monitor-repair work is initiated in the most ing system instrumentation shall be expeditious canner to return the determined operable:

, failed component to an operable

! state, and Specifications 3.5.A.5 a. At least once per operating cycle l and 3.5.F are satisfied. The NRC by demonstrating the operability i shall be notified within 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> of over-voltage, under-voltage l of the situation, the precautions and under-frequency protective

! to be taken during this period and instrumentation by performance of j the plans to return the failed a channel calibration including components to an operable state. simulated automatic actuation of j the protective relays, tripping

d. RPS/MG Sets logic and output circuit breakers and verifying the following set-l

1. With one RPS electric power monitor- points.

I ing channel for an inservice RPS MG l set or alternate power supply inop- 1. Over-voltage $ 132 VAC, with erable, restore the inoperable chan- time delay < 2 sec, nel to operable status within 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br /> or remove the associated RPS 2. Under-voltage 3 108 VAC, with

MG set or alternate power supply time delay 5 2 sec.

l from service. l

3. Under-frequency 3 57 Hz. with

2. With both RPS electric power moni- time delay < 2 sec.

.l toring channels for an inservice RPS l MG set or alternate power supply in-

! operable, restore at least one to

operable status within 30 minutes or

, remove the associated RPS MG set or alternate power supply from service.

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3.9 BASES The general objective of this Specification is to assure an adequate source of electrical power to operate the auxiliaries during plant operation, to operate facilities to cool and lubricate the plant during shutdown and to operate the engineered safeguards following the accident. There are three sources of ac electrical energy available; namely, the startup transformer, the emergency transformer and two diesel generators. The de supply is required for switch gear and engineered safety feature systems. This supply consists of two 125V DC and two 250V DC batteries and their related chargers. Specification 3.9.A states the required availability of ac and de power; i.e., active off-site ac

sources and the required amount of on-site ac and de sources.

Auxiliary power for CNS is supplied from the startup transformer and the normal

. transformer. Both of these transformers are sized to carry 100% of l the station auxiliary load. The emergency transformer is about one third the

size of these two transformers and is equal in size to both emergency diesel generators.

The startup transformer and the emergency transformers are the offsite power sources. Their voltage is monitored by undervoltage relays which provide low voltage protection for the emergency buses. Whenever the voltage setpoint and time delay limit for the undervoltage relays have been exceeded, the emergency buses are automatically disconnected from the offsite power source.

If the startup or emergency transformer is lost, the unit can continue to operate since the unit auxiliary transformer is in service, and the emergency or startup i transformer and the diesels are available.

! If both the startup and emergency transformers become inoperable, the power

level must be reduced to a value where by the unit can safely reject the load i

and continue to supply auxiliary electric power to the station.

I In the normal mode of operation, the startup and emergency transformers are energized and two diesel generators are operable. One diesel generator may i

be allowed out of service based on the availability of power from the startup ,

transformer and the fact that one diesel generator carries sufficient engineered safeguards equipment to cover all breakers. With the startup transformer and one diesel generator out of service, the off site transmission line corresponding to the emergency transformer must be available. Upen the loss of one on-site and one off-site power source, power would be available from the other immediate off-site power source and the two operable on-site diesels to carry sufficient engineered safeguards equipment to cover all breaks. In addition to these two power sources, removal of the Isolated Phase Bus " quick" disconnect links would allow backfeed of power through the main transformer to the unit auxiliary transformer and provide power to carry the full station auxiliary load. The time required to perform this operation is comparable to the time the reactor could remain on RCIC operation before controlled depressurization need be initiated.

A battery charger is supplied with each of the 125/250 Volt batteries. The 125 Volt battery system shall have a minimum of 105 Volts at the battery terminals to be considered operable. The 250 Volt battery system shall have a minimum of 212 Volts at the battery terminals to be considered operable.

These values are based on a minimum of 1.75 Volts per cell (each 250 Volt battery has 121 cells and each 125 Volt battery has 60 cells).

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1 3.9 BASES (cont'd) - . - . . .

Replacement criteria for 125V and 250V station batteries is <85% capacity factor and the maximum time for replacement should be one (1) year. This will assure that the remaining battery capacity is adequate to meet load requirements.

4.9 BASES The monthly test of the diesel generator is conducted to check for equipment failures and deterioration. Testing is conducted up to equilibrium operating conditions to demonstrate proper operation at these conditions. The diesel generator will be manually started, synchronized and connected to the bus

and load picked up. The diesel generator should be loaded to at least 50%

It is expected that the diesel

> of rated load to prevent fouling of the engine.

generator will be run for'at least two hours. Diesel generator experience at other generating stations indicates that the testing frequency is adequate i and provides a high reliability of operation should the system be required.

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Each diesel generator has two air compressors and two air receivers for i

starting. It is expected that the air compressors will run only infrequently.

' During the monthly check of the diesel generator, each receiver in each set of receivers will be drawn down below the point at which the corresponding compressor automatically starts to check operation and the ability of the compressors to recharge the receivers.

The diesel generator fuel consumption rate at full load is approximately 275 gallons per hour. Thus, the conthly load test of the diesel generators will l

j test the operation and the ability of the fuel oil transfer pumps to refill

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the day tank and will check the operation of these pumps from the emergency

! source.

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The test of the diesel generator during the refueling outage will be more comprehensive in that it will functionally test the system; i.e, it will check diesel generator starting and closure of diesel generator breaker and sequencing of load on the diesel generator. The diesel generator will be started by simulation of a loss-of-coolant accident. In addition, an undervoltage condition will be imposed to simulate a loss of off-site power.

Periodic tests between refueling outages verify the ability of the diesel generator to run at full load and the core and containment cooling pumps to deliver full flow. Periodic testing of the various components, plus a func-tional test once-a-cycle, is sufficient to maintain adequate reliability.

Although station batteries will deteriorate with time, utility experience indicates there is almost no possibility of precipitous failure. The type of surveillance described in this specification is that which has been demonstrated over the years to provide an indication of a cell becoming irregular or unserviceable long before it becomes a failure. In addition, the checks described also provide adequate indication that the batteries have the speci-fled ampere-hour capability.

The diesel fuel oil quality must be checked to ensure proper operation of the diesel generators. Water content should be minimized because water in the fuel could contribute to excessive damage to the diesel engine.

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l 4.9 BASES (cont'd)

When it is determined that some auxiliary electrical equipment is out of service, the increased surveillance required in Section 4.5.F is deemed adequate to provide assurance that the remaining equipment will be operable.

The Reactor Protection System (RPS) is equipped with a seismically qualified,

Class lE power monitoring system. This system consists of eight Electrical Pr'otection Assemblies (EPA) which isolate the power sources from the RPS if the input voltage and frequency are not within limits specified for safe system operation. Isolation of RPS power causes that RPS division to fail safe.

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