Nuclear Instrumentation Rod Blocks and Scrams Flashcards
When does the SRM Short Period alarm actuate?
When power is changing by a factor of E shorter than 50 seconds
How are SRM Rod Blocks and Scrams bypassed?
Mode Switch in RUN, or the SRM is bypassed
What is the purpose of the Shorting Links?
With the Shorting Links installed all SRM Scrams are bypassed.
What conditions would produce an SRM INOP signal?
1) SRM Mode Selector Switch not in OPERATE 2) High volts 3) Low volts 4)Card out of file
What SRM signals produce a Rod Block?
1) INOP 2) Downscale at 0.7 cps 3) <100 cps and detector not full in 4) Upscale at 1E5 cps
What is required to bypass the SRM Downscale signal that produces a Rod Block?
1) Both of the associated IRMs on range 3 or greater 2) Both of the associated IRMs on range 8 or greater
What is required to bypass the SRM <100 cps and detector not full in Rod Block?
1) Both of the associated IRMs on range 3 or greater 2) Both of the associated IRMs on range 8 or greater
What is required to bypass the SRM Upscale signal that produces a Rod Block?
Both of the associated IRMs on range 8 or greater
What SRM signals produce a Reactor Scram?
1) INOP 2) Hi Hi at 2E5 cps
How are IRM Rod Blocks and Scrams bypassed?
Mode switch in RUN, or the IRM is bypassed
What conditions would give an IRM INOP signal?
1) IRM Mode Selector Switch not in OPERATE 2) High volts 3) Low volts 4)Card out of file
What IRM signals produce a Rod Block?
1) INOP 2) Downscale at 5/125 3) Upscale 80/125 4) Detector not full in
What is required to bypass the IRM Downscale signal that produces a Rod Block?
The IRM Range Switch on range 1
What IRM signals produce a Reactor Scram?
1) INOP 2) Hi Hi 120/125
OPRMs produce Reactor Scram signals based on what three monitoring functions?
1) Period 2) Amplitude 3) Growth Rate
What is the only OPRM monitoring function that is required by Tech Specs?
Period
What conditions would give an APRM INOP signal?
1) Switch not in operate 2) High volts 3) Low volts 4) Card not in file 5) Flow card switch not in operate 6) Less than 14 LPRM inputs
What APRM signals produce a Rod Block?
1) INOP 2) Downscale 3) Total Recirc Flow 4) Flow Bias Upscale 5) Neutron Upscale Fixed
What is the APRM Rod Block Downscale setpoint?
Less than 4% Reactor Power
What is the APRM Rod Block Total Recirc Flow setpoint?
Greater than 111% flow
What is the APRM Rod Block Flow Bais Upscale setpoint?
Greater than .628 x Recirc Flow + 55% clamped at 108%
What is the APRM Rod Block Neutron Upscale Fixed setpoint?
Greater than 12% Reactor Power
What is required to bypass the APRM Rod Block Neutron Upscale Fixed signal?
Mode Switch in RUN
What is required to bypass the APRM Rod Block Downscale, Total Recirc Flow, and Flow Bias Upscale signals?
Mode Switch NOT in RUN
