Equipment Failure Procedure

PS-09 PE-15 10/22/62

A. Primary Pump Failure

• 1. Shut pump down open disconnect switches on B & D group controls and tag controls.
• 2. Reduce reactor power to within operating pump limitations.
• 3. If failure does not affect required plant power level, continue operation.
• 4. Failure of a second primary pump necessitates plant shutdown and repair of pumps.

B. Primary System Gate Valve Fails to Operate by Remote Control

• 1. Continue reactor operation until a normal shutdown, at which time valve repair shall be completed.
• 2. Tag inoperable valve controls.

C. Primary System Check Valve Fails Closed

• 1. Secure its primary pump. Lock and tag out controls.
• 2. Operate plant within power limitations.

D. Primary System Check Valve Fails Open

• 1. Reduce power level for one loop operation.
• 2. De-energize remaining pump in loop and switch pump assiciated with defective check valve to half speed. Monitor all loop flows and temperatures.
• 3. Close loop reactor inlet gate valve and de-energize primary pump. Lock and tag valve and pump controls.
• 4. Repair defective check valve during first reactor outage.

E. Primary Water Leakage Through Failed Steam Generator Tube

• 1. Reactor plant shall be shutdown.
• 2. Secure primary gate valves in suspected loop.
• 3. Secure steam stop valves, blowdown and feedwater valves for suspected steam generator.

F. Pressurizer Spray Control Valve Failure PE-1V or PE-3V

• 1. If a pressurizer spray valve does not respond correctly to manual or automatic signals the alternate valve must be used.
• 2. Lock and tag out deffective valve controls<

G. Pressurizer Spray Valve Fails to Close and the Leakage is Sufficient to Collapse the Steam Blanket in the Pressurizer

• 1. Close cut-off sprage valve PE-2V. Lock and tag the faulty spray valve controls.
• 2. Control primary system pressure by intermittant operation of PE-2V and proceed with a normal shutdown.

H. Pressurizer Heater Element or Bank Failure

NOTE: Once at operating level, reactor primary system pressure can be maintained by the two smallest heater banks, 1 and 2. Therefore, approximately 80% of the total heater capacity can be lost without seriously affecting plant operation.

• 1. Defective heater banks should be de-energized with controls locked and tagged off.
• 2. IF all heater banks fail, proceed with reactor shutdown and cooldown.

I. Failure of Pressure Control for the Spray Valves and Heater Banks (PIRCA-PE2)

NOTE: The failure of this instrument would affect the automatic spray and heater bank operation.

• 1. Switch to alternate pressurizer pressure transmitter.
• 2. Switch to "HAND" operation of spray vavles and heater banks.
• 3. Monitor pressurizer level and pressure failure following failure.
• 4. This instrument also controls the setpoint on the pressurizer relief valve PR-3V. If this valve begins to relieve un-controlled, close PR-2V and manually regulate PR-2V as necessary.

J. Inability to Control or Monitor Pressurizer Level (Possible failure of LICA-PE1)

• 1. Switch to alternate level transmitter. Tag out faulty selection position.
• 2. Complete failure of this instrument results in loss of level, makeup and heater control. An immediate reactor plant shutdown is necessary.
• 3. Carefully observe pressurizer temperatures at the main console.

K. Failure of Pressurizer Temperature Indication (TIRA-PE3)

NOTE: With all pressurizer pressure and level instrumentation functioning, failure of one or both temperature sensing elements our their instrument can be tolerated. The undesireability of this failure is pronounced in reactor startup and severe pressure load chances.

• 1. Tag out the instrument.
• 2. Strict observance of allowable pressure, temperature standards must be exercised.
• 3. Maintain pressurizer level close to normal.
• 4. Instrument shall be corrected ant tested prior to the next normal reactor startup.

L. Failure of the Temperature Indicator Used to Monitor Surge Line Temperatures and Surges During Heatup (TI-PE4)

NOTE: This instrument is used primarily for information, and if the pressurizer and primary system temperatures are within specified limits, it is not necessary for reactor operation.

• 1. Tag off TI-PE4.

M. Failure of the Pitch and Roll Compensating Instrument

• 1. If at sea close surveillance of pressurizer and boiler levels is required.
• 2. Tag out instrument.
• 3. Should level control become impossible shutdown the reactor.

N. Primary Flow Loop Instrumentation Failure Causing Incorrect Flow Indications

• 1. Particular loop flow instrument shall be tagged out at its indicators.
• 2. Reactor operation may continue with constant monitoring of loop temperatures and steam generator and steam flow.

O. Failure of Reactor Outlet Temperature Instrument (two elements) Used as a Safety System Input

• 1. If safety system input is selected to "SINGLE" ant one failure (open circuit) will result in a reactor scram. At that time repair instrument.
• 2. If safety system is in "COINCIDENT" failure of one input can be tolerated, until a shutdown when repair can be accomplished.

P. Failure of Any of the Loop Temperature Instruments. (Such as delta T, Tave, Tin, or Tout

Port Loop	TVI-PS2		Stbd. Loop	TVI-PS1
		TDI-PS2				TDI-PS1
		TIR-PS2				TIR-PS1

Both Loops	TVIA-PS14

• 1. Switch to manual mode of reactor operation.
• 2. Closely monitor remaining affected loop parameters. Tag out faulty instruments.
• 3. Switch to alternate resistance temperature element or repair instrument, resuming normal operation.

Q. Failure of Primary System PRessure Instrumentation (PIRA-PS5)

NOTE: Failure of any one of the two micro switch inputs to the safety system will scram the reactor.

• 1. Switch to alternate sensing element. Tag out faulty instrument.
• 2. Should alternate signal be lost without a reactor scram, difficulty is outside containment. Monitor pressurizer pressure.
• 3. If difficulty cannot be corrected, initiate reactor shutdown.