SESS Flashcards
What is the Safety Equipment Status System (SESS) Function / Design Bases?
- To monitor the status of Engineered Safety Features (ESF) equipment and alert the control room operator by distinct visual and audible means when any of the monitored ESF equipment becomes inoperable or bypassed. (White Light)
- To monitor the status of ESF components in the event of an ESFAS and alert the control room operator by distinct visual and audible means when any of the monitored ESF component did not complete transition to the required safe operating position. (Blue Light)
What conditions can cause a white SEIS light for ‘A’ HPSI pump?
1) Supply breaker is not fully racked in
2) Control power is removed (RRA breaker open or control power fuses removed)
3) 86 lockout is tripped
4) Closing springs are discharged
What conditions are required for a blue SEAS light for ‘A’ HPSI pump?
‘A’ train SIAS & ‘A’ HPSI pump supply breaker is open. (ESFAS actuation and component is not in actuated position)
When should the control room staff enter a manual SESS alarm?
Entered when a system is rendered inoperable by a non-alarmed function or when directed by procedure.
What is the purpose of the Safety Equipment Inoperable Status (SEIS) portion of the Safety Equipment Status System?
To monitor the status of the Engineered Safety Features (ESF) equipment and alert the control room operator by distinct visual and audible means when any of the monitored ESF equipment becomes inoperable or bypassed.
What is the purpose of the Safety Equipment Actuation Status (SEAS) portion of the Safety Equipment Status System?
To monitor the status of Engineered Safety Features (ESF) components in the event of an ESF actuation signal and alert the control room operator by distinct visual and audible means when any of the monitored ESF components did not complete transition to the required safe operating position.
What is the power supply for SESS?
The SESS Panels receive power from the ‘A’ Train and ‘B’ Train 125 VDC Class Distribution buses (PK)
How does SESS interact with PPS?
SESS receives safety signal inputs from PPS.
Describe the interaction between SESS and QSPDS (SH).
SESS sends the status of Containment Isolation Valves to QSPDS.
Describe the Safety Equipment Inoperable Status (SEIS) sub-system.
The Safety Equipment Inoperable Status (SEIS) sub-system indicates any specific component of safety equipment which has been rendered inoperable by illuminating a white light on the component level indicator panel.
Describe the Safety Equipment Actuation Status (SEAS) sub-system.
The Safety Equipment Actuation Status (SEAS) sub-system indicates any specific component of safety equipment that does not transfer to its safe position upon the receipt of a safety actuation signal by illuminating a blue light on the component level indicator panel.
What does the SESS ‘ALARM RESET’ button do?
Acknowledges alarms received on the associated system level window cabinet by silencing the audible device (either SEIS or SEAS tone); the ‘ALARM RESET’ does not affect window or component indicator panel lamp operation.
What does the SESS ‘FLASHER RESET’ button do?
Changes a fast flashing window to steady on for sustained alarms, or a fast flashing window to slow flashing for momentary alarms.
What does the SESS ‘LAMP RESET’ button do?
Changes a slow flashing window to off after the alarm condition has cleared.
What does the SESS ‘BYPASS/INOP TEST’ button do?
Simulates an alarm condition for all SEIS inputs; lights all system level alarm windows (white fast flashing) and component level indicator (white steady on) lamps; testing is completed by operating the reset buttons.
