EDG Flashcards
EDG Loss of power TS
Two loss of voltage and two degraded voltage function relays operable
modes 1-4
parameters of the overcrank alarm and the actions
EDG will alarm if cranking signal present for 45 seconds and EDG speed <300 rpm
Take EDG to lockout
design of T-57s
22.5k gallons each
gravity fed
provide 3.5 days of fuel per diesel
fuel system numbers (p-16 a/s & hi dis, t-57 level, day tank #’s & alarms, fo priming pump)
- P-16s a/s 180 gal in day tank, stop @ 240 gal
- fuel oil priming pumps start on edg a/s and stop @ 300 rpm
- P-16 hi discharge press @ 30 psig
- t-57 low @ 155”
- day tank lo level alarm if <180 gal for >3 min
Fuel oil pump is attached to scavenging LO pump and riven from shaft or electrically?
shaft driven
what speed is mechanical overspeed trip
990-1045 rpm
Main lube oil pressure EDG trip
17 psig
Diesel run indication provided when main lube oil pressure is ____.
20 psig
immersion maintain lube oil at what temps
energizes at 125F and deenergizes at 155F
immersion heat is on water side
purpose of soakback pumps
maintain engine oiled and ready to start
immersion heater purpose
warms lube oil for fast start. on water side
compressors cycle on and off at __
on at 186 psig
off at 200 psig
Tech spec for air receiver pressure
<175 psig causes inop of EDG
Receiver tanks are good for ___ starts from each set.
5 starts @ 175 psig
what will disengage air start motors?
engine rpm>300 rpm
air start for 8 seconds
main lo pressure >20 psig
how often do air start motors swap?
2.5 seconds if engine <30 rpm
overcrank alarm
45 seconds
3.8.3 - fuel oil and starting air
fuel oil and starting air within limits
Applicability: when EDG req’d to be operable
3.8.1 - AC Sources
two offsite power sources
two diesels
modes 1-4
1 of four inop, perform SR in 1 hour
3 of 4 inop, 3.0.3
3.8.2 AC Sources shutdown
1 offsite power source
1 diesel
modes 5 and 6
generator specs
3 phase, 2750 kw, 4160v, 60 hz
max starting time 15 seconds
field flashing circuit powered from ___?
125vdv D-11/D-21
A/S for EDGs
ES 1 OR 2 will start both diesels
UV on A3/A4 - 3300.5V for 2.3 seconds
UV on B5/B6 - 429.6V for 8 seconds
UV on B5/B6 - ES Signal present 407.6V for 3.3 seconds
Autostart permissives
- control switch not in maint
- E-trip relay not energized
- lockout switch not in lockout
- trip relay not energized
- output brkr not in PTL
E-Trip relay energized
- mech overspeed 990-1045 rpm
- lo lube oil press <17psig (blocked until 300 rpm & 20 seconds)
- pos crankcase press 0.8”-2.5”
- local e-stop
edg lockout relay energized on:
- gen phase diff
- overcurrent
- loss of gen field w/ gen brkr shut
- gen motoring
- engine trip on K-11
start pilot relay de-energized:
- control selected to maint
- C-10 switch in lockout
- K-11 relay energized
- EDG lockout relay tripped
- local/remote stop PB pushed
ways to stop engine manually
- in CR
- local stop pushbutton (disabled on ES)
- load limit control on gov
- fuel shutoff valve
- switch in maintenance
Vital Bus Loads
HPI - 602 kw LPI - 305 Spray - 203 SW - 305 B5/B6 - 900/900 P-7B - 500
EDG Start sequence
- A/S signal received
- run solenoid energized
- gov boost motor energized
-air start motors alt every 2.5 secs until >30 rpm
and will disengage at 300 rpm, 8 sec after start signal, 20 psig LO press
-fuel priming pump/gov boost motor deenergize at 300 rpm
Functions of Voltage regulator and Gov control when not on grid or tied to bus.
voltage reg - adjusts voltage
gov control - adjsuts freq
Functions of Voltage regulator and Gov control when tied to the grid
Voltage reg - reactive loading
gov control - adjust kw
