Reactor Plant Protection and Safety Final
Why does the reactor coolant pump mechanical seal have three stages? - correct
answer-Because of the large pressure drop across the seal
During normal operations, steam generator water level experiences _____ during a _____
transient. - correct answer-shrink; down-power
What is the purpose of the moisture separators and dryers in the steam generator?
(SELECT ALL THAT APPLY.) - correct answer-To ensure 100% Quality steam is provided to
the turbine. To mix with the incoming feedwater to prevent thermal stress on the tube sheet
What is the motive force for normal spray flow in the pressurizer? - correct answer-Pressure
drop across the core
If Pressurizer level is 55" when average coolant temperature is 579F, what level in the
Pressurizer would most likely correspond with an average coolant temperature drop to 575F,
assuming all other conditions are held constant? - correct answer-50"
Which of the following are functions of the Chemical and Volume Control System? (Select all
that apply.) - correct answer-Maintain water inventory in the RCS. Provide seal injection for
RCP seals. Add chemicals to the RCS. Provide means to adjust boron concentration of the
reactor coolant. Reduce corrosion and fission products in the reactor coolant
Which of the following would be indications of a steam generator tube rupture? (Select all
that apply.) - correct answer-Decreasing pressurizer level. Increasing steam generator level.
Steam line radiation monitors alarms.
If the steam generator is operating with a secondary side pressure of 1000 psig and the load
on the main turbine is increased which of the following secondary side pressure indications
would you expect to observe? - correct answer-900 psig
_____ is a soluble poison used in the reactor core. - correct answer-Boron
Which of the following are fission product barriers? (Select all that apply.) - correct
answer-Fuel rods. Cladding. Reactor vessel. Reactor coolant piping. Containment. Reactor
coolant pump pressure boundary
What component provides overpressure protection for the RCS pressure boundary? - correct
answer-Pressurizer code safety valves
Control rods have a _____ cross section for absorption of _____ neutrons. - correct
answer-high, thermal
Which one of the following IS NOT a function of the reactor coolant system? - correct
answer-Protects against pressure boundary over-pressurization
, During a reactor trip which rods are released and allowed to drop into the core by gravity? -
correct answer-All rods
_____ range instruments typically use _____. (SELECT ALL THAT APPLY.) - correct
answer-Source; proportional counters
What is the purpose of a discriminator circuit? - correct answer-Eliminates pulses due to
alpha particles and gamma rays
What type of detector is used for incore neutron detection? - correct answer-fission chamber
Which of the following increases the signal to noise ratio? - correct answer-Two step
amplification with the first amplifier close to the detector
Which one of the following is a purpose of the rod control system? - correct answer-Provide
immediate shutdown capability
What is the purpose of a differentiator in a source range nuclear instrument circuit? - correct
answer-To measure the rate of change of the neutron flux
_____ nuclear instruments are used for _____ . - correct answer-Excore; reactor protection
and control
Why are three ranges used to monitor reactor power level over the full range of reactor
operation? - correct answer-No single instrument can adequately cover such an extensive
range and at the same time provide acceptable accuracy
Why are two motor generators provided to power the control rod drive mechanisms? -
correct answer-For redundancy in case of failure
What is meant by the term coincidence logic? - correct answer-A specific number of multiple
channels must indicate tripped in order to generate reactor trip or safeguard functions
Which of the following components are included in the Safety Injection System? (SELECT
ALL THAT APPLY.) - correct answer-High head safety injection pumps
Residual heat removal (RHR) pumps
Accumulator tanks
Why is gamma compensation not required in the power range? (SELECT ALL THAT
APPLY.) - correct answer-Neutrons significantly outnumber gammas. Gammas are
proportional to reactor power
How are the reactor trip breakers connected and why? - correct answer-Series; to ensure
power is disconnected from the CRDMs should either one of the breakers fail to open with a
trip signal present
Why does the reactor coolant pump mechanical seal have three stages? - correct
answer-Because of the large pressure drop across the seal
During normal operations, steam generator water level experiences _____ during a _____
transient. - correct answer-shrink; down-power
What is the purpose of the moisture separators and dryers in the steam generator?
(SELECT ALL THAT APPLY.) - correct answer-To ensure 100% Quality steam is provided to
the turbine. To mix with the incoming feedwater to prevent thermal stress on the tube sheet
What is the motive force for normal spray flow in the pressurizer? - correct answer-Pressure
drop across the core
If Pressurizer level is 55" when average coolant temperature is 579F, what level in the
Pressurizer would most likely correspond with an average coolant temperature drop to 575F,
assuming all other conditions are held constant? - correct answer-50"
Which of the following are functions of the Chemical and Volume Control System? (Select all
that apply.) - correct answer-Maintain water inventory in the RCS. Provide seal injection for
RCP seals. Add chemicals to the RCS. Provide means to adjust boron concentration of the
reactor coolant. Reduce corrosion and fission products in the reactor coolant
Which of the following would be indications of a steam generator tube rupture? (Select all
that apply.) - correct answer-Decreasing pressurizer level. Increasing steam generator level.
Steam line radiation monitors alarms.
If the steam generator is operating with a secondary side pressure of 1000 psig and the load
on the main turbine is increased which of the following secondary side pressure indications
would you expect to observe? - correct answer-900 psig
_____ is a soluble poison used in the reactor core. - correct answer-Boron
Which of the following are fission product barriers? (Select all that apply.) - correct
answer-Fuel rods. Cladding. Reactor vessel. Reactor coolant piping. Containment. Reactor
coolant pump pressure boundary
What component provides overpressure protection for the RCS pressure boundary? - correct
answer-Pressurizer code safety valves
Control rods have a _____ cross section for absorption of _____ neutrons. - correct
answer-high, thermal
Which one of the following IS NOT a function of the reactor coolant system? - correct
answer-Protects against pressure boundary over-pressurization
, During a reactor trip which rods are released and allowed to drop into the core by gravity? -
correct answer-All rods
_____ range instruments typically use _____. (SELECT ALL THAT APPLY.) - correct
answer-Source; proportional counters
What is the purpose of a discriminator circuit? - correct answer-Eliminates pulses due to
alpha particles and gamma rays
What type of detector is used for incore neutron detection? - correct answer-fission chamber
Which of the following increases the signal to noise ratio? - correct answer-Two step
amplification with the first amplifier close to the detector
Which one of the following is a purpose of the rod control system? - correct answer-Provide
immediate shutdown capability
What is the purpose of a differentiator in a source range nuclear instrument circuit? - correct
answer-To measure the rate of change of the neutron flux
_____ nuclear instruments are used for _____ . - correct answer-Excore; reactor protection
and control
Why are three ranges used to monitor reactor power level over the full range of reactor
operation? - correct answer-No single instrument can adequately cover such an extensive
range and at the same time provide acceptable accuracy
Why are two motor generators provided to power the control rod drive mechanisms? -
correct answer-For redundancy in case of failure
What is meant by the term coincidence logic? - correct answer-A specific number of multiple
channels must indicate tripped in order to generate reactor trip or safeguard functions
Which of the following components are included in the Safety Injection System? (SELECT
ALL THAT APPLY.) - correct answer-High head safety injection pumps
Residual heat removal (RHR) pumps
Accumulator tanks
Why is gamma compensation not required in the power range? (SELECT ALL THAT
APPLY.) - correct answer-Neutrons significantly outnumber gammas. Gammas are
proportional to reactor power
How are the reactor trip breakers connected and why? - correct answer-Series; to ensure
power is disconnected from the CRDMs should either one of the breakers fail to open with a
trip signal present
