QSPDS

Question 1

What are the three saturation margins and how are they calculated?

Answer 1

RCS saturation margin
-hottest of the RCS hot and cold leg RTDs

Upper head saturation margin
-hottest of the temperatures from the top three unheated juntion thermocouples

RepCet (representative CET saturation margin)
-representative CET temperature statistically derived from all valid CET inputs

Question 2

What is the purpose of QSPDS?

Answer 2

Functions primarily to provide indication to detect approach to the existence of and recovery from in adequate core cooling

Question 3

How can you tell if the QSPDS computer program is not frozen?

Answer 3

heartbeat square

Question 4

How can you tell if an input to QSPDS is bad?

What if it is just suspect?

Answer 4

multiple “?’s”

a single ‘?’ at the beginning of the reading

Question 5

What are the power supplies for QSPDS?

Answer 5

A - PNA-D25
B - PNB-D26

isolation cabinets from PNC-D27 and PND-D28

Question 6

What important parameters are monitored/displayed on QSPDS?

Answer 6

• Pressurizer Level
• Pressurizer Pressure
• SG level
• SG pressure
• SG pressure differential
  ○ Indicative of flow through RCS
• AFW flow to SG
• Containment
  ○ Pressure
  ○ Sump level (WR)
  ○ H2 concentration
  ○ Area Radiation
  ○ Primary coolant area radiation
• CST level
• Reactor log power
• RCS wide range pressure
• Reactor vessel level status
• Isolation valve (CIAS) status
  ○ Signal is all CIV’s close on CIAS

Question 7

What train of QSPDS sends signals to the recorders on Board 2?

Answer 7

“A” train only

Question 8

Adequate core cooling ensure fuel clad temperature remains below what temperature?

Answer 8

2200*F

Question 9

How is lowering level indicated in the core?

Answer 9

in step changes.

when level is lowering, it shows the level of the most recently uncovered HJTC until the next HJTC is uncovered, then it will show the next lower level

Question 10

If an RCP is running, is the Plenum Reactor Vessel Level considered valid?

Answer 10

no