EPMS Flashcards
What components are on the hot battery bus?
MIK switch
Cold refuel panel
HPSM 1/2 CONT
Battery description
FNC
20 cells
12 min at 80%
24 Vdc 15 Amp
Battery components
Internal heater (-40 C operations / on at -10 rdy in 30min) Heater temp sensor (overtemp protection) Battery temp sensor (signal to charger / control rate of recharge)
When does GCU under frequency protection start?
Ground 365 - 380 Hz (2+/-1 sec)
Air 306 Hz (75% RPM)
When does GCU over current protection start?
235 amps +/-5 CCR is opened in 5-7 secs
What are the GCU protections?
Over voltage Under voltage Over current Under frequency Feeder fault
What does HPSM1 supply power to?
ELC1, CBP1, ECS1, FCR
What does HPSM2 supply power to?
ELC2, CBP2, ECS2, Control logic for battery charger
ELC components?
68020 processor board
2 I/O modules
3 SP controlled relays modules (mux fails - last commanded position)
PSU1 DC 5+-15 Vdc
PSU2 26 Vac ABC ref for FMC, SP1/2, WP1/2 StabSyncros, 10 Vac for ENG1/2 oil psi transducer and xmsn transducers, 10 Vdc for VCP and BPIA
Where is the external power module?
Behind the LMP
Where is the CB for external power (EXT PWR INTLK)?
Next to LMP
Where does GCU DC backup power come from?
GCU1 - CBP2 | GCU2 CPB1
When can you not do an EPMS IBIT?
Airborne ENG start or override APU start or stop Manual generator trip Fuel boost operation Zeroize operation XFEED operation
Battery only operations?
WBP1 + 2 are HPSM bus bars (hot)
HPSM1 = KBP01 (Cold Refuel) KBP02 (MIK) KBP10 (SP1 power)
HPSM2 = KBP10 (SP2 power)
KB101/201 (30amps) prevent the battery from powering HPSM until MIK in BATT
When HPSM is powered KB103/203 (50 amps) provide power to CBP1/2
KB102/202 (30 amps) provide 28 Vdc to WB3/4 in ELC1/2 design to trip in overcurrent condition
KD1D1 and KD2D1 block voltage to WD1 and WD2
Battery Bus nomenclature?
WB1 + WB2 = HSPM1/2 Bus
WB3 + WB4 = ELC1/2 Bus
WB5 + WB6 = CBP1/2 Bus