Misc 126 Flashcards
Why are the H2 coolers on the 176 foot of the turbine building cracked open?
Keep air out since it is the system high point
At what pressure does the standby TCW pump start at?
55 psig on the header
What indications do you expect on the TCW surge tank?
- Level approx. 46-51”
- N2 pressure around 25-30 psig
What is normal instrument air header pressure?
115 psig
When do we get a low IA header pressure alarm?
95 psig
When does the backup N2 align to the IA header?
At approx 85 psig
What cools the IA compressors and service air compressor?
TCW
If TCW is out, what can cool the IA/SA compressors?
DS
What is the H2 storage bank normally maintained at?
Around 2300 psig
When do we get a low H2 storage bank pressure alarm?
200 psig
When does the emergency seal oil pump auto start?
At approx. 110 psig
How much does H2 purity degrade when we lose a main generator seal oil vacuum pump?
around 2% every 8 hours. Air will continually be absorbed by the seal oil system, migrating through the H2 seal and degrading H2 purity.
In all three units which condenser shell expansion joints are wet?
Only unit 3’s ‘B’ expansion joint
At what pressure is the H2 maintained in the Generator at?
75 psig. You can see it on rounds by the seal oil skid.
How is seal oil maintained in regards to H2?
Around 8 psig greater than H2 pressure.
What is the normal pressure in the seal oil tank?
26-27” Hg vac
What is normal stator cooling winding flow? When is the alarm? Trip?
Normal- 645-677 gpm
Alarm- 581 gpm
Trip- 549 gpm
What is the normal pressure for the main seal oil pump?
around 250 psig
What is the normal pressure for the Main Turbine LO cooler inlet bearing header pressure?
48 psig
What is the normal MTLO temperature when we are running?
110-120 degrees F
When do we use the 15 gpm or 30 gpm setting on the MTLO conditioner?
Below 100 degrees F- 15 gpm
Above 100 degrees F- 30 gpm
What is the normal main shaft oil pump suction pressure?
25 psig
What is the normal Bearing header pressure?
25 psig
What is the normal Operating oil pressure?
225 psig
If a critical steam trap is out of service; how often do we need to blow it down?
once every 6 hours
What are the critical steam traps?
M23 and M24
What is normal TCW pump discharge pressure?
95-115 psig
When walking around transformers; what are you generally checking for?
- oil leaks
- Unusual noises or odors
- Cooling coils/fans for blockage
- Bushings chipped or cracked
- Bushing oil levels
- N2 Pressures
- Sevron panel status
- Gas analyzer status
- Annunciator panel check
- Oil temperatures
- Mechanical relief device
