Systems Comp Study Sesh Flashcards
Explain the SDG sequence.
Senses UV
Opens MDS
Starts SDGs
First up to speed closes in
Second diesel auto synchs
Tie Breaker closes
If there is a differential on the BMC/CMC Transformer, how does the protective scheme work?
Both high and low side opens at the same time, then the creoss tie will close without any delay
How does the Degraded Bus Voltage work?
Sensed on A & D T Buses
9 sec delay for alarm. If SI or LoLo SG, then loadshed
+90 seconds of correction before Fast transfer to RATs
+21 seconds of RATs trying to correct before Load Shed
If sensed on A or D, that whole train will be loadshed
What is the normal source of power to the CRIDs?
250 vDC
What is the alternate power source to the CRIDs?
600 vAC
Which 600 v bus goes with which CRID?
C -1
D -2
A - 3
B - 4
What does the In Synch light being lit on the CRID tell you?
Alternate source is available
What does the ALT Source to Load PB on the CRID do?
electronically transfers on static switch to alternate source of power
How does the Auto Retransfer Lockout work on the CRID?
After transfer to the alternate load, if the event clears, and is normal for 30 seconds, the statis switch auto transfers the load back to the normal source. If a 2nd transfer to alt source occurs before the autoretransfer capability is reset manually, the alternate source supplies the load. The static transfer switch locks out on alternate source until reset.
What does a rectifier do?
Changes AC to DC
What normally powers the batteries?
Battery Chargers from 600 vAC
What is the order of starts with time delays for all the fire pumps?
Motor/Electric 140 psi for 2 secs
East Diesel 130 psi for 15 secs
West Diesel 120 psi for 25 secs
What are the SDGs sized for?
1 Unit, 1 Train of RCS Inventory Control
How does the LoadShed Scheme work?
Sensed on EACH T Bus at 94 (93) Volts and lowering for 2 seconds. Loadsheds that one bus
If there is a differential on the B/C bus 600 v transformer, will that bus be powered from the EDG?
NO. No high side disconnect, so entire bus is dropped
Who has command function?
Shift Manager
What is the fire protection provided to both Units CRCVs?
Auto Halon
Manual CO2
Auto Water for Unit 2 Only
Define the Modes of Operation Per Tech Specs
Mode 1 - Keff Greater than or equal to 0.99 and Rated Thermal Power > 5%
Mode 2- Keff Greater than or equal to 0.99 and Rated Thermal Power less than or equal to 5%
Mode 3 - Keff < 0.99 and RCS Tavg Greater than or equal to 350 degrees
Mode 4 - Keff < 0.99 and RCS Tavg btween 200 and 350 degrees
Mode 5 - Keff < 0.99 and RCS Tavg less than or equal to 200 degrees
What is the pressure safety limit?
2735 psi
If the safety limit for pressure is violated, what must be done?
Modes 1&2, Be in Mode 3 and restore within 1 hour
Modes 3-5, Restore within 5 mins
Whats the purpose of the safety limits in section 2 of Tech Specs?
Protect from fuel damage and maintain vessel integrity.
Who is responsible for overall safe operations?
Plant Manager
What are the Tech Spec credited sources for Offsite Power?
RATs and EP
SDGs are NOT credited
What is the normal Split Bus alignment?
BXfmr 5 to Train B
Xfmr 9 to Train A
BD is Open
What is the purpose of Xfmr 4?
Connects the 345 and 765 kV Yards
What are the requirements regarding shift staffing?
May be less than minimum for less than or equal to 2 hours for unexpected absence, provided immediate action is take to restore
If a surveillance is MISSED, what must be done?
Performed within 24 hours or the normal surveillance frequency, whichever is GREATER
Can Grace be applied to the first performance of an EIS?
Nope! Only subsequent
How much grace is allowed for surveillances?
25%
What is the maximum extension time for a TS Entry?
additional 24 hours from the first inoperability, without making the second INOP go greater than the original spec time
What supplies power to the pressurizer heaters?
T Busses A & D
What causes a load conservation?
LOOP + SI/CTS
How are the Plant Batteries Sized?
4 hours for SBO
What are the trips available to the EDGs during a SI or LOOP?
Generator Phase Differntial
Electronic Overspeed at 110%
Manual Push Button
If using the control switch, must HOLD it to keep if from restarting.
What is the minimum pressure in the EDG Air Receiver?
190 psi
What is the minimum volume of the Diesel FOST? Good for how long?
> 46,000 gallons good for 1 EDG at full load for 7 days
What happens if the electronic governor for the EDG fails high?
speed rises and machine will be controlled by the mechanical governor (if not paralleled, otheriwse speed droop takes over and grid maintains speed)
If control air is lost, will the EDG continue to run / start?
No! Throttle Control Cylinder will be extended, stopping fuel
where is the EDG field flash powered from?
1 kV interter until 80% speed
When do the LO upper valve gears open for the EDGs?
ON the EDG start signal (95% run relay)
What is the Circ Water Pump Auto Start?
failure of running pump, if the control switch is in AUTO
What is a Circ Water Pump Trip?
Undervoltage on associated 4 kV Bus
When does the circ water pump discharge valve auto open?
on auto pump start only, NOT manual
What are the power supplies to the CW Pumps?
1 - D
2 - A
3 - B
4 -C
RCP Buses
What does De-Ice Look like?
WMO-30 is closed
WMO-16 or WMO-26 Open
done slowly to prevent debris agitation
Which valves are used if the center intake is crushed?
WMO-17/27
What are the Tech Spec Pressure Limits for containment?
-1.5 psig to +0.3 psig
What are the tech spec containment temperature limits?
Upper = 60-100 degress
Lower = 60-120 degrees
What are the power supplies to SFP Pumps?
North = 11C
South = 21C
What will isolate CCW to the SFP Hx?
Phase A
If there is a rupture on the suction piping for the SFP Pump, what is the lowest the water will drain below the normal level?
19 inches
Will X-tie through SFP purification piping prevent boiling?
No! Just delays it
Per the bases, why is there greater than 23 feet of water above the fuel?
Iodine Decon Factor
What are the NESW Pump Auto Starts?
Load Shed
SI
Low Pressure 55 (60) psi in auto
*For pressure, it is unit specific. A low pressure on Unit 1 N NESW will start the Unit 1 S NESW. It will not autostart any Unit 2 pumps
What are the ESW Pump auto starts?
SI - Either Unit, Train Specific
Load Shed
Low Header Pressure of 40 psig in AUTO
If the EDG starts but power is lost to the normal cooling valve is lost (A/D did not repower ), will the EDG have cooling?
Manual from Opposite train is available, but without Operator Action, NO
What happens to ESW from CCW Hx on a SI?
Throttles to ~5,000 gpm
What are the auto starts of the CCW Pumps?
SI
Load Shed
Low pressure on running pump discharge of 80 psi if in AUTO
What is the makeup to the CCW Surge Tank?
MANUAL Demin Water
What happens on a high rad in the CCW Surge Tank?
Vent Valve (CRV-412) goes closed
What happense to the CCW Hx Outlet valves on a SI?
They go Full Open
What happens to the CCW Outlets from RHR Hx on a SI?
Throttles to ~3500 gpm
What manual action must be done on a Phase B?
RCPs must be tripped because CCW has been isolated to the thermal barrier and MACs
What happens on a Low Low Glycol Expansion Tank LeveL?
Outside containment isolation valves VCR-10 and 20 close
Glycol Expansion Tank Outlet Valves VSO-20 and 21 Close
Which Containment Fans trip on a Phase B?
CLVs
CRDMs
Prssurizer Fans
Rx Cavity Fans
What happens if an odd numbered radiation monitor receives a High Rad Signal? (ie. 1300 or 2300)
Inside Containment Valves close and Instrument Room Purge Supply Fan Trips
What happens if an even numbered radiation monitor receives a High Rad Signal? (ie. 1400 or 2400)
Outside containment isolation valves close and all fans other than instrument room purge supply trip
Where do CEQ Fans take suction?
SG Enclosures
Pzr Doghouse
CLV Fan Rooms
Instrument Room
What are the auto starts of the AES Fans?
ECCS Pump Starts
SI
(Train Specific)
Train Specific
What accident condition will place the AES Fan in charcoal filter mode?
Phase B
Where do AES Fans take suction from?
Vestibule
CTS and RHR Hx Roms
SI, RHR, CCP and CTS Pump Rooms
When moving fuel, what happens on a High Rad on RRC-330?
Fuel Supply Fans TRIP
Filter Bypass Damper gets a close signal
Charcoal filter inlet face dampers gets an open signal
If air is lost to VRV-315/325 for the control room chilers, how does it fail?
full flow to chillers
How do the control room dampers fail on a CRCV fire?
1/1A Closed
2/2A Part Open
3 Closed
Control Room Pressurization Fan also auto starts.
How do the control room dampers fail on a Hi Rad Alarm?
1/1A Closed
2/2A Part Open
3 Open
How do the control room dampers fail on a SI?
1/1A Closed
2/2A Part Open
3 Open
How are the control room dampers aligned on a toxic gas?
All dampers are manually closed!
When cross-tying the 600 vAC buses 11B and 11C, how is it done?
Break before Make. Crosstie has to see the normal feeder breaker open. These come from the T buses, and may be out of phase, depending on the power supply to the T bus.
When cross-tying the 600 vAC buses BMC and CMC, how is it done?
Make before Break because they come from the RCP buses and will ALWAYS be in phase.
What is the purpose of the volts over herts alarm?
Telling operators that there is too much excitation which could lead to damage due to voltage. Will cause a trip if the turbine is not paralleled.
What voltage does the main generator exciter produce?
3 phase AC that gets rectified and sent to the main generator.
Where is 11PHA and 11PHC powered from?
11PHA - T11A
11PHC - T11D
What is the power supply to the logic cabinets for Rod Control?
120 vAC which was stepped down from the 260 vAC from the MG Set Output.
What powers the CRIDs on a loss of all AC?
the 250 vDC Batteries
What powers the slave relays for Train A?
CRID 1 (120 vAC)
What powers the slave relays for Train B?
CRID 4 (120 vAC)
What is the DIRECT result of pushing the emergency trip push botton?
Unit HEA trips
the button is in the UNIT
What happens if the excitation breaker to the generator opens at power?
Excitation is lost and the HEAs will trip
What prevents you from opening the exciter field breaker at power?
Interlocked with the generator output breaker.
When paralleling the EDG, how do you prevent becoming a load on the grid?
By making sure EDG frequency is slightly higer than the grid. (Slow in the fast direction)
What are the 3 parameters on the Generator Capability Curve?
Hydrogen Pressure
Vars
Megawatts
What is the purpose of the Thyristor / Converter?
to turn AC into DC
(fancy names for rectifiers)
What happens if the TSCUPS battery is lost?
Nothing. It is normally supplied by 11C
Where are the AB/CD battery chargers normally supplied from?
600v Vital Buses
What happens to a pump if 250 vDC control power is lost?
Pump cannot be operated remotedly. Protective trips are also unavailable.
Where does the voltage regulator sense voltage?
At the output of the main generator
How can you lower amperage to lessen heat if bus duct cooling temperature is a concern?
Get closer to Unity. So, in MVARs are in, raise voltage. If MVARS are out, lower voltage.
Where are the Generator output breakers powered from?
125 vDC Yard Power
Unit 1 is from 345 kV yard
Unit 2 is from 765 kV yard
How is the anti-pumping circuit cleared?
Taking control switch to TRIP
How does the protection scheme for BMC/CMC work if there is a high current sensed on the transformer?
Transformer output breaker (low side) opens
If the high current remains, then it is faulted and the HEA will trip
If no longer sensed, then the high side breaker will open and another signal is sent to reopen the low side.
11BCMC will close to repower the bus
How do the master valves for CO2 fail on a loss of DC?
OPEN
What is the maximum number of fire pumps expected to be running at any time?
2! For a unit 1 main transformer fire.
How do the selector valves for fail on a loss of DC?
CLOSED
If the invidividual selector switch is in isolate for CO2, what protection is available?
No automatic. Only manual.
How does CO2 put out a fire?
It displaces Oxygen
Can the Before and After pump provide all the LO needed for the EDG while it is running?
NO! Engine/Shaft drive pump is required.
What trips are available to the EDG if 250 vDC is lost?
Worthington manual fuel valve
Mechanical Overspeed at 112% of 514 RPMs
Will the EDG stay running if the 250 vDC is lost?
Yep!
What is the design of the fuel oil transfer pumps?
Both will start on low level and cycle off and on to maintain level
If there is a hole in the downstream piping of the starting air receiver, will the EDG still start?
Yes! Only one starting air valve is needed, but the crosstie downstream gets air to all of the cylinders
What are the indication that the field flash did not work?
No field volts
Why is the EDG INOP during surveillance testing?
A loadshed signal will not be generated.
What are the loads on the EDG 1 kV Inverter?
Field Flash Power
Local / Remote Control Transfer Relays
Dynalco Speed Transmitters
Bearing Temp Monitor (SG 40)
How do the EDG Starting air valves fail on a loss of control air?
As Is
What will cause the EDG ventilation to start?
EDG Start or 95 degree room Temp
What can cause the EDG supply/exhaust fans to stop?
CO2 Actuation, 70 degree room temperature or 30 minutes after EDG is shutdown
What are the 3 parts to the Hi-Storm Dry Cask System?
- Hi-Storm Overpack
- MPC
- Hi-TRAC Transfer
What main purpose does the MPC serve?
Confinement boudnary
Why is helium used in the MPC?
Cooling, Inert atmosphere to prevent chemical reaction with fuel cladding and leak detection.
What is the purpose of the COC?
Approves the design of the dry cask storage system.
What produces most of the heat in the SFP ?
Fission products
What is a support function of the SFP System?
Used to clean up the RWST
How does a NESW pump respond to a loadshed with a CTS?
The pump will restart with the loadshed and then trip
What happens to the NESW system on a Load Conservation?
LO Cooler WMOs close
NESW closes to CUVs, CIRs and MACS
Unit cross tie to the misc hder closes
What supplies control air to the strainer backwash for ESW?
Unit 1
What supplies a backup water supply to the Aux Feed Pumps?
East ESW Header = MDAFPs
West ESW Header = TDAFPs
What would happen if ESW was lost to the CRAC?
They may trip without a Heatsink
What does Containment Chill water provide cooling for?
CLVs, CUVs and CIRs
RCP MACs
SG BD Hx
What is the purpose of the divider barrier seal?
Prevents flow of steam and air from bypassing the ice condenser
What are the autostarts for the control room pressurization fan?
Either Unit SI (Train Specific)
High Radiation (Unit Specific)
CRCV Fire
If control air is lost to VRV-315/325 (CR Vent Unit Chillwater Control Valves), How does it fail?
Full flow to the chiller
What are the flow rates for the containment Purge system design?
Lower containment at 21,000 CFM
Upper containment at 11,000 CFM
What is the flow path for the Purge supply and Exhaust?
Supply - Roughin Filter to Med Efficiency Filter to Steam Heater to Fan
Exhaust - HEPA Filter to Fan
*Fans are located on AUX BUILDING Roof
How does a loss of control air to aux building ventilation effect the dampers?
Face Damper failrs Open
Bypass Damper Fails Closed
What will autostart the CEQ Fan and make the valves reposition?
1.0 psi in containment on a separate signal than the Phase A
How will VDC-207 (CONTAINMENT PRESSURE RELIEF VENTILATION UNIT INLET VOLUME DAMPER) fail is control air is lost?
Full Flow
During refueling, the divider barrier and missile blocks separating the reactor cavity from the refueling cavity are removed. This causes higher flow rates in the purge exhaust system. What is the benefit of this?
Prevents the formation of vaport clouds on the water, which will keep the whiny refuelers from complaining.
What will auto start the CCW Pump Fans?
Unit specific Load Conservation
What are the key pressures for the compressed air system?
97 psig - Standby PAC Starts
90 psig - CAC Starts (sensed in wet air receiver)
85 psig - PA Hdr Isolation Valves Close
80 psig - manual reactor trip
What trips the PAC?
Loadshed
Load Conservation
Overload
(Low LO Pressure, High LO Temp and a few other things that don’t matter as much)
What trips the CAC?
DOES NOT LOADSHED
Overload, Low Oil Pressure, Low NESW Pressure
What are the interlocks for the CAC Start?
NESW and Oil Pressures
Where does the backup PAC tie into the air system?
Between the ring header isolations. If isolations are closed, it can still provide control air.
What is the control air flowpath?
Intake to CAC to aftercooler/Moisture Sep to Wet Air Receiver to Filters and dryers to dry air receives to valves
If there is a leak between the 2 units plant air header isolation valves, can control air still be provided?
YES! There are check valves.
In standby alignment, which valves are normally opened and normalled closed for the CTS System?
Suction and Eductor Valves OPEN
Pump Discharge and SAT Outlet Valves CLOSED
What signal starts the CTS Pump?
Phase B
What signal repositions valves in the CTS System?
CTS Signal
What is the purpose of using NaOH in containment spray?
Removes radioactive elemental iodinde from containment atmosphere during a DBA
What would the potential side effect be if the contects of the SAT never made it into containment?
Corrosion
What is the low end and high end of the 7-10 pH band for in the SAT?
Low - Keeps iodine in solution
High - Avoids chlroide and caustic stress corrosions on equipemnt
What is the purose of the nitrogen blanket in the SAT?
Prevents diluting the NaOH
What happens prior to the Low Low SAT Level and why?
SAT Outlet and Eductor Supply valves close to prevent gas binding the pump
How is temperature of the hydrogen recombiners controlled?
Controlling the power to them
What will autostart a hotwell pump?
Low pressure at 130 (110) psig
What will autostart a CBP?
Low pressure at 325 psig
When will hood spray automatically go in serivce?
Generator Load < 7.5% with Turbine Speed > 900 RPM
What is the TS Minimum for the CST and the bases?
182,000 gallons for 9 hours steaming in Mode 3 assuming loss of offsite power
What are the power supplies to the CBPs and HWPs?
RCP Buses
North - D
Middle - A
South - C
What triggers the recirc valves for the CBP to open?
Flow Switch at the discharge of the pump
For the low pressure heater strings, how much flow capaity is provedied by each sting?
LP 1 Heaters (3 of them) = 50% flow capacity each
LP Heaters 2-4 (2 strings) = 80% flow capacity each
What is the purpose of CRV-224, LP Heater Bypass Valve? How much flow is it good for?
Maintains 210-240 psig at the MFP Suction
Good for 20% bypass flow
What are the autostarts for the TACW Pumps?
Low discharge pressure at 155 (145) psig
What are the TACW Loads?
Bus Duct Cooling
Hydrogen Coolers
Steam Packng Exhauster / Gland Steam Condensers
Exciter Coolers
Stator Water Coolers
Where does TACW system tap into condensate at?
Between the discharge of the hotwell pumps and the excess flow line to the CSTs.
How does open vs closed cycle effect TACW efficiency?
Open Cycle = more efficient
Closed Cycle = Less efficient bc rejectiong heat to Circ Water
How is CMO-600 positioned for the various operational cycles of TACW?
Open Cycle = Full Open
Closed Cycle and Modified Cycle = Throttled as needed.
What are the hardwired MFP Trips?
MR. SHIT
Manual
Rx Trip
SI
Hi Hih SG Level
IOPS at 110%
Thrust Bearing Wear
What are the PLC MFP Trips?
Overspeed at 107%
Low Condenser Vacuum
Low Lube Oil Pressure (4 psig for 5 secs)
Low Suction Pressure (180 psig for 5 secs)
Low Trip Hdr Pressure at 800 psig
When operating at different power levels, different steam sources are utilized for the MFPs. What are they for low and high power?
0 - 60% power = Main Steam
> ~60% power = Reheat Steam
What will give a Feedwater Isolation?
SG High High at 67% on 2/3 on 1 SG
SI
Rx Trip (P-4) with Low Tave at 554 degrees
What will autostart the MFP Seal Water Pump?
< 15 psid between the CBP Discharge and MFP Suction pressures
What are the available water sources for the MFP Seal Water Pump?
Normal = CBP Discharge Pump
Alternate = MFP Seal Water pump from U1 CST or HWP Discharge
What is utilized to set the DP Target on the MFPs?
Total Steam Flow
How is actual MFP DP calculated?
Uses the highest of the Bypass Header Steam Pressures (UPC-102a/b) and the lowest of the FW Pressures (FPC-250a/b)
What is the purpose of a thrust bearing?
prevents axial movement to prevent stationary and rotating blade contact
What is the purpose of a thrust bearing?
prevents axial movement
How do the runbacks work on a loss of a main feed pump for both units?
Unit 1 sets target to 625 MW. Not active until then. Runs back at 600 MW/Min
Unit 2 sets target to 752 MW. Not active until then. Runs back at 1000 MW/Min at first, then at 140 MW/Min
If Main Steam pressure fails, How does Steam flow fail?
Steam pressure is density compensated. SF will fail the same direction as steam pressure.
Can different SG Level channels be selected for control?
NO! Always the middle channel.
When it comes to SG Water Level Control, what is dominant?
LEVEL! Always tries to get back to 43.8% if the failure ins’t too bad, and there is enough time.
What are the setpoints for the SG PORVs and Safeties? What is the equivalent power?
PORV - 1025 psig
2 Safeties - 1065 psig
2 Safeties - 1075 psig
1 Safety - 1085 psig
Each PORV is worth ~ 2.5% power
Each Safety is worth ~ 5 % power
What is the purpose of the lockout position on the SGSV Dump Valves?
allows closing dump valves with a SLI standing to prevent the release, since there is not way to reset the SLI signal (if its standing, its in!)
What will give a SI?
1lb in lower containment 2/3
1775 psig 2/3
< 500 psig on 1/1 on 2 SGs
DP between steamlines > 100 psid with 1 SG lower than 2 others on 2/3 instruments
What’s the design bases of the SG PORVs?
Prevents lifting the safeties and to Cooldown to RHR in manual
If the CRID is on its Alternate source, what does operability look like?
Inverter INOP but CRID Bus is OPERABLE
If a CRID is on CRP-3, what does operability look like?
CRID BUS and Inverter are both INOPERABLE
What will give a Steam Line Isolation?
< 500 psig on 1/1 on 2/4 SGs
> 2.8 psig in containment 2/4
> High Steam Flow on 1/2 on 2/4 SGs with Low Low Tave at 541 degrees (P-12)
How do SGSV Dump Valves fail on loss of air?
OPEN, which will close the SGSV
How do SGSV Dump Valves fail on loss of power?
CLOSED, which will keep the SGSV open
What is the TS Bases for the MS Safety Valves?
Ensures secondary Steam pressures will be limited to 110% of desired pressure during most severe anticipated operational transient
Backup for RCS primary Pressure
How many PORV Rad Monitors are there?
2 monitors, 4 detectors
How many PORV Rad Monitors are there?
2 monitors, 4 detectors located downstream of the PORVs
When is the PORV Rad Monitor inoperable?
Any time the PORV is isolated (even if just manual from the control room)
What are the autostarts of the MDAFP?
Both MFPs Trip (if switch is in auto)
AMSAC (if active. So > 40% on MPC-253/254)
Loadshed
Low Low SG Level 2/3 on 1/4 SG
SI
What are the autostarts for the TDAFP?
Undervoltage on RCP Bus (1/2 on 2/4 buses at 88V)
SG Low Low 2/3 on 2/4 SGs
AMSAC (if active. So > 40% on MPC-253/254)
How do you know if it is the electronic overspeed vs the mechanical overspeed that tripped the TDAFP?
If it is the electronic overspeed, drop 50 will clear once the seal in is reset after running the TTV closed.
What is the difference bewtween a flow conservation signal and a flow retention signal?
Flow Retention protects against run out after a steam/feed break
Flow Conservation conserves inventory by closing the AFW Test Valves and SG BD Isolation Valves.
Flow Retention will override the Flow Conservation
How is C-20 met to enable AMSAC?
2/2 first starge turbine impulse pressures > 40%
What will actuate AMSAC?
Feed Flow < 25% on 3/4 (1 channel from each SG)
What does AMSAC Do?
Trips the Turbine and starts all AFW Pumps
What will a high radiation signal in the CCW System dO?
Close the vent valve on the surve tank. CRV-412. Once the high rad signal is clear, the valve may be reopened without any system realignments
What will a high rad signal do on DRA-300? How is this different from DRA-353?
Closes DRV-350
Closes SGBD Isolations
Closes BD Sampling Valves
IF it is DRA- 353, ALSO trips the blowdown treatment pump
Where is SG Level measured?
In the downcomer
What could cause SG Level to shrink?
reduction in steam flow
What could cause SG Level to swell?
increase in steam flow
What are the Low Level SG Reactor Trips?
Unit 1
5%
15% with SF/FF mismatch of 0.71 Million Lbm/hr
Unit 2
22%
26% with SF/FF mismatch of 1.47 Million Lbm/hr
How are SGSVs opened and closed?
Hydraulic to Open
Steam to Close
How many acoustic monitors are there for the pressurizer Safeties?
1 for each safety.
How many acoustic monitors are there for the pressurizer PORVs?
1 acoustic monitor. All PORVs share it.
Where do the Moisture Seperator Drains Go?
To the same heater that the HDPs take suction from.
Unit 1 = 5 Heaters
Unit 2 = 4 Heaters
Where do the Reaheater Coil Drain Tanks drain to?
The 6 Heaters
What will trip a HDP?
Both Suction Valves Closed (Trip Middle HDP)
Low Low Level in suction Heater
Main Turbin Trip
Overload/Overcurrent
What is the purpose of the Bleed Steam Air Assis Check Valves?
Close to prevent turbine overspeed.
What is the purpose of steam dumps?
Non-Safety Related system to handle a step load reduction of 40% without the use of rod control
What are the Turbine Trip and Load Rejection controllers based on for steam dumps?
Auctioneered High Tave
What is the only CRID that has no steam dump loads?
CRID 3
What is C9?
1 CW Pump Breaker Closed
CRID 2 Energized
3/3 Condenser Vacuums Greater than or equal to 20.6 in Hg
If on the Load Rejection controller, how far will dumps bring you back in temperature?
Within 5 degrees of Tref
What is the turbine trip control comparing Tave to?
T No Load (547 degrees)
What is the load rejection controller comparing Tave to?
Tref
What is the purpose of bypass interlock on steam dumps?
allows ofr 1 group of dumps to operate for a cooldown to go below P-12.
What is P-12?
Blocking Signal that tells dumps to close unless bypass Interlock is selected.
2/4 Tave < 541 degrees
How many groups of valves are available on the turbine trip controller? What are the temperature deviations that will cause those valves to trip open?
2 groups (6 valves)
Group one trips open at 10 degrees
Group 2 trips open at 20 degrees
How many groups of drumps are available during a load rejection? How does the temperature deviation work on the load rejction controller?
10% rejection = 2 groups
30% rejection = 3 groups
Valves trip open at 9, 13 and 17 degree. Start opening at 5 degree deviation
If on the steam pressure controller, what effect will there be if UPC-101 fails?
Hi = Cool down to P-12, or if interlock is already bypassed, 1 group opens until there is operator action.
Low = All open valves will close
If there is a turbine trip and Tave fails high, what happens?
Valves will open to reduce temperature until 547 degrees. It won’t see that right away. Dumps will not close until P-12 is met.
Will a failure of MPC-253 or MPC-254 affect steam dumps?
Not unless there is also a temperature deivaition. If on the turbine trip controller, it will have no effect either because it’s not being looked at.
What is the purpose of the Generator brushes?
Make contact with the collector rings to cmplete the current flow path between the stationary and rotating coilds
What are the SCW Trips for Unit 1 Main Turbine?
81 degrees C after 15 secs
Low Flow at 499 gpm for 10 secs
Low Oil Pressure at 36 psig for 10 secs
What are the SCW Trips for the Unit 2 Main Trubine?
95 degrees C after 15 secs
Low Flow at 666 gpm for 10 secs
Low Oil Pressure at 28 psig for 10 secs
There is also a manual trip at 18 micro mhso/cm conductivity
What are the autostarts for the SCW Pumps?
Unit 1 - 130 psig low pressure
Unit 2 - 80 psig low pressure of low flow of 845 gpm
What is warmer, SCW or cold gas temp?
SCW is 3-4 degrees C greater than Cold Gas Temp to avoid condensation
What is the auto makeup to the SCW Tank?
Demin Water
What is the purpose of the teflon connectors use in SCW?
Provides electrical insulation between the stator bars and the system piping.
During outages, how do we get air in the Main Generator?
Use CO2 to purge the hydrogen, then use air.
What pressure is the hydrogen in the Main Generator online?
Unit 1 = 75 psig
Unit 2 = 60 psig
What does the generator condition monitor look for?
products of combustion
What is the puropuse of GSO-251 closing ?
closes at 50 psig to prevent a hydrogen leak into the turbine building.
What will trip the seal oil vacuum pumps?
High tank level. Will restart when it recovers
What is the purpose of hte Unit 1 seal oil recirc pump?
Recirc the contents of the seal oil tank to retard foaming and aid in degassin
Which pump can the unit not survice the loss of for Unit 2 Seal Oil?
Air Oil
How do the Unit 2 seal oil pressures work for Air, Vac and Hydrogen Oil ?
Air oil is 7 psi greater than generator hydrogen pressure
Vacuum Oil is 6 psig greater than air oil
hydrogen oil is equal to vacuum oil
What is the flowpath for bus duct cooling for each unit?
Unit 1 is out the middle phase and back the North and South.
Unit 2 is out the South Phase and back the North and Middle.
What will autostart a bus duct fan?
LOW FLOW!
What are the hardwired Main Turbine Trips?
ASS MOISTURE
AMSAC
SI
SG Level High High
Manual
Overall HEA
IOPS at 110%
SCW Loss
Thrust Bearing Wear abnormal
Unit HEA
Reactor Trip
Emergency Trip
What are the PLC trips for the Main Turbine?
Low Condenser Vaccum at 22.5 in Hg
Overspeed at 107%
Oil Pressure < 8 psig (14.7 psig) for 5 secs
Low EHC Header Pressure < 1100 psig
Low trip header pressure 2/3 < 800 psig
Loss of both DCS Power Supplies
Which LO Pumps start on a Unit 1 Turbine Trip?
AC Suction Oil Pump
Turbning Gear Oil Pump
DC Backup Oil Pumps
DC Bearing Oil Pumps
ALL BUT LIFT PUMPS
What do Unit 1 steam seals look like at a low power?
SRV-10, the pegging valve, will be throttled as necessary until ~50% power
SRV-11, the dump valve, will be closed.
What autostarts the bearing lift pumps?
Unit 1 = Low Speed of Turbine
Unit 2 = Turbine Trip
How do you adjust the galnd steam condenser vacuum?
Adjust the blower suction inlet orifice plate (sliding damper) position
What is the purpose of backseating the Unit 2 Main Turbine?
Minimize packing leakage by isolating system pressure from the packing and stuffing box.
When is the power load unbalance runback active?
> 40% 1st stage impulse pressure
What does a power load unbalance runback look like?
30 MW at 1389 Mw/Min in MW OUT
Where is IOPS powered from?
CRIDS 1, 2 and 3
What is the load target on a OP or OT Delta T Runback?
30 MW
Will a failure of all 3 PLC Speed sensore trip the Main Turbine?
ONLY when NOT paralleled.
What is the purpose of the exhuase hood spray?
Prevents the LPT lades from overheating.
What does MW IN mean?
Valves will move around to maintain a constant MW
What does MW Out mean?
Valves will maintaing their position based on a curve. MW will swing around with lake temperature changes.
what will autostart a CCP?
SI
What is the bases for the maximum VCT Pressure? How about minimum?
37 psig - ensure adequate emergency boration flow
15 psig - during RCP operations for RCP seal # 2 flow
What do QLC-451/452 do?
QLC-451 starts makeup at 14% and stops at 24%. It also Trips open to divert flow to the CVCS HUTs at 87%
QLC-452 starts diverting at 78% with a full divert at 87%
2/2 at 2.5% will give a Refueling Water Sequence, which will transfer suction of the CCPs over to the RWST
What happens to the CVCS system on a Phase A?
LD Orifice valves close
LD CIVs Close
Seal Return Valves Close
CCW to XS LD Hx Closes
What happens to CVCS on a SI?
Charging Hdr Isolation Valves Close
CCW to LD Hx Closes
CCP Recrics close for 2 secs then modulate on pressure (1812-1825 psig)
CCP Suction relaigns to RWST
BIT valves open
CCP Starts
What must be done when emergency borating?
shift BAT Pumps to FAST manually
What can cause flashing in the letdown line?
Chargin flow too low or QRV-301 too far open
If QCM-250/350 fails closed, where is your seal leak off going?
PRT
If QCR-300 or QCR-301 LD Containment CIVs fail closed, where does letdown go?
Assumin orific valves are still open with flow, then to the PRT
What would cause the LD orifice valves to close?
Close when either LD Isolation valve QRV-111/112 are closed
Close if a CCP Breaker is open
Pzr Level 17%
Phase A
At what temperature does the Demin Divert Valve (QRV-302) fail to the VCT?
143 degrees
What is the purpose of the throttle valves in the ECCS injection loops?
Flow balancing to ensure all loops will get the same flow.
What is utilized if Seal Injection is lost to the RCPs?
rcs via the thermal barrier
What instruments do the CCP Recirc valves look at?
East CCP QMO-225 looks at NPP-151
West CCP QMO-226 looks at NPP-153
NR Pressurizer Pressure
What is the concern if seal line resistance isn’t within it’s TS Value?
If it is too small, ECCS injection flow may be less than required for core cooling during a LOCA.
What is the purpose of the reactor vessel head vent system?
remove noncondensable from the RCS
Sized to not exceed capability of one charging pump
What are the interlocks for starting a RCP?
Bearing lift motor started closed
Bearing lift oil pressure > 510 psig
other than the interlock met, what is needed to start a RCP?
No 1 seal DP > 215 psid
VCT Pressure > 15 psig
Cooling aligned
What are the power supplies to the RCPs?
RCP Buses
1 - B
2 - C
3 - D
4 - A
What is the purpose of the RCP Flywheel?
Helps remove decay heat immediately after the trip
How many lines go in and come out of containment for CCW to the RCPS?
1 line in for both the bearing oil cooler and the thermal barrier
2 lines out, so that a thermal barrier leak can be isolated (it’d get all 4 RCPs)
What is the seal injection flowpath for RCPs?
3 gpm thru #1 seal
3 gph thru #2 seal
100 cc/hr thru #3 seal
What is the seal return flowpath for the RCPs?
1 seal to CCP suction (or VCT during outages)
#2 seal to the standpipe and then to RCDT
#3 seal to outlet of RCDT.
When starting a RCP, what is the seal dp looking at?
CCP Pressure - VCT Pressure
What are the normal parameters for the PRT?
100 degrees
83%
3-5 psig
When in LTOP, what instruments feed into the PORVs?
WR RCS Pressure
NRV-152 controlled by NPS-122
NRV-153 controlled by NPS -121
What will trip the Pressurizer backup heaters?
Loadshed (train specific)
Low Level at 17% in PZR
Overcurrent
Which pressurilzer level insturment failure will close QRV-111?
Bistable channel failuer Low
Which pressurilzer level insturment failure will close QRV-112?
control channel failure low
Take time to study all level and pressure instrument failures
Bistable level channel failing high does nothin g
All level failures will eventually result in a reactor tirp on high pressurizer level in > P-7
If Pressurizer Pressure fails high, then 1/2 of an input to a PORV to open exists. Won’t open bc the confirmatory isn’t there
If a Pressurizer pressure fails low, then you may have at least 1 inoperable PORV
What are the TS Values for the accumulators?
921-971 cubic feet
585-658 psig
2400-2600 ppm
Applicable in modes 1, 2 and 3 if > 1000#
What are the TS Values for the RWST?
375,500 gallons
2400-2600 ppm
70-100 degrees
What is the ECCS Acceptance Criteria?
Peak Clad temperature < 2200 degrees
Max Cladding oxidation < 17%
Hydrogen generation < 1%
Core maintains a coolable geometry
Long term cooling
What does the design anaylsis assume for accumulators?
1 dumps all contents out the break, but core remains partiall covered.
What is required to Open ICM-305, RHR Suction from the recirc sump?
IMO-310 RHR Suction from RWST AND IMO-215 CTS Suction from RWST CLOSED.
What is required to Piggy back? (Open IMO-340)
On rceirc sump and not sendig water back to RSWT.
IMO-305, RHR Suction from Recirc OPEN and IMO-262 OR IMO-263, SI Recirc to RWST CLOSED
What is required to open IMO-330, RHR to Upper Spray?
RHR Suction from Recirc valve IMO-305 OPEN
What is required to open IMO-310, RHR Suction from RWST?
Not on Recirc Sump, Not piggy Backing, Not on RHR Spray
ICM-305, IMO-340 and IMO-33 all closed
What is the low level trip for the RHR Pump?
9% RWST level with IMO-310/320 Open
What is the interlock to open IMO-128 and ICM-129 (RHR Suction from Loop 2 HL)?
< 411 psig on RCS Wide Leg Pressure
IMO-128 looks at NPS-122
ICM-129 looks at NPS-121
what does a high radiation signal on RRS-1000 do?
Trips closed RRV-285
Trips off the MT / WECT Pump selected for release
How does a loss of CW Pumps effect your liquid waste system?
Trips the unit specific release valve RRV-286/287
Where do floor drais on the 609 elevation and above go?
DWHUT
Where do hard piped drains on the 609 elevation and above go?
CWHUT
Where to floor drains on the 587 elevation go?
DW Sump Tank
Where do hard piped drains on the 587 elevation go?
CW Sump Tank
What will cause a GDT to swap to the standby tank ?
100 psig
Hi Hi Oxygen at 2.7% on the AOM
What is the interlock to open RRV-306 for the waste gas release flow control valve?
at least 1 Unit 1 AX Fan running
What will cause RRV-306 for the waste gas release flow control valve to close?
High Radiation on either unit vent stack rad monitors VRS-1500/2500
Loss of BOTH Unit 1 AB Exhaust fans
What is the purpose of the variable gain unit in rod control?
Increases output at lower power because a given reactivity change at low power has a smaller effect on power than at high power
What are the inputs to Rod Control?
Auctioneered High Tave
Auctioneerd High PRNI
MPC-253
How fast do rods move in manual?
48 steps per minute
How fast do the rods move for shutdown banks whe moved individually?
62 steps per minute, with no indication for C and D
How fast do rods move in automatic?
8 steps per minute from 1.5 - 3.0 degrees
for 3-5 degrees, they move 32 steps per degree +8
What is the purpose of bank overlap?
Provide a more uniform axial power distribution and more uniform DRW
Where are rod bottom lights powered from?
CRP-3
What are the conditionals for Rods?
C-1, Intermediate Range Rod Stop
- 1/2 IRNI > 18% (16%)
- Stops AUTO and MANUAL rod withdraw
- can be blocked based on P-10
C-2, Power Range Rod Stop
- 1/4 PRNI > 103%
- Stops AUTO and MANUAL rod withdraw
- C-2 blocked when ROD STOP BYPASS selected to alarming channel
C-3, OTΔT Rod Stop (Can’t be blocked)
- 2/4 PRNI 3% < trip setpoint
- Stops AUTO and MANUAL rod withdraw.
C-4, OPΔT Rod Stop (Can’t be blocked)
- 2/4 PRNI 3% < trip setpoint
- Stops AUTO and MANUAL rod withdraw.
C-5, Turbine Power Interlock (Can’t be blocked)
- MPC-253 < 15%
- Stops AUTO only rod withdraw
C-11 Control Bank D Rod Stop (Can’t be blocked)
- CBD @ 229 steps (cycle dependant)
- Stops AUTO only rod withdraw
What happens to Rod Control if a PR NI Fails? What about MPC-253? How about Tave?
PR NI High: Rods Step In due to power rate of change. Rod Stop (C2) may prevent rods from stepping out on temp error (auto & manual)
PR NI Low: No effect unless affected instrument was previously auctioneered high.
MPC-253 High (Tref ˃ 577.9): Rods Step Out due to power rate of change and Tavg < Tref
MPC-253 Low (Tref ≤ 547): Rods Step In due to Power rate of change and Tavg > Tref
Tavg High: Rods Step In because Tavg > Tref
What is the cause of the urgent failure when recovering a misaligned rod?
Generated in the other bank of rods in that power cabinet due to all lift coil disconnect switches open for that entire group
What are the inputs into the subcooling meter?
Auctioneered High CETCs OR WR RTD
Auctioneered Low WR RVLIS Pressure
Why is RVLIS pressure used in the subcooling meter calc?
Its located outside of containment and not susceptable to containment atmosphere during an accident.
Per TS 3.4.11 (PORVs), what must be done with 1 or more inoperable PORV with manual control available?
Close block valve and maintain power on valve within 1 hour.
What are the inputs to the waste gas vent hheader?
RCDT
CVCS HUTs
VCT
PRT
AGA
SRST
