.  
OFF.-The.Generator.field.is de-energized.and.the.line.contactor opens. The.fault.circuit.is reset.

.  
Fault.Light.-.Illuminates amber.if a protection.trip.is initiated.by the Generator.control unit.(GCU),.or.the line contactor opens without selecting the.respective GEN.switch.OFF.

.

APU.GEN.Switch
.  
ON.-.The.Generator.field.is energized and.the.line.contactor.closes provided electrical parameters.are.normal and the.EXT.PWR.line.contactor.is open. The.bus tie.contactor.(1.and/or.2) automatically.closes if generators.1 and/or.2.are.not operating.

.  
OFF.-The.Generator.field.is de-energized.and.the.line.contactor opens. The.fault.circuit.is reset.

.  
Fault.Light.-.Illuminates amber.if a protection.trip.is initiated.by the Generator.control unit.(GCU),.or.the line contactor opens without selecting the.APU GEN.switch OFF..The APU GEN.FAULT.light.is.inhibited.when APU.speed.is low.

.

BUS.TIE.Switch
.  AUTO.-.The.Bus.Tie.contactors.open or.close.automatically to.maintain power.supply.to.AC.buses 1.and.2.
One.contactor is closed.when.one engine-driven.generator.supplies the associated.AC.bus and.the.APU generator.or.external.power.supplies the.other.side.
Both.contactors.are.closed.in.case.of one.engine-driven.generator, or external power.supply.
.  OFF.-.Both Bus.Tie.contactors.are open.
.

EXT PWR.Switch
When pushed.with.the.EXT PWR AVAIL.light illuminated:
.  
External.Power.line contactor closes

.  
AVAIL.light goes off

. ONlight.illuminates When pushed.with.the.EXT PWR ON.light illuminated:
.  
External.Power.line contactor opens

.  
ON light.goes.off

.  
AVAIL.light.illuminates

AVAIL.Light.-Illuminates green.provided External.Power.is plugged.in.and.electrical parameters.are.normal.

12.11.06  -.21-

Air.Conditioning
PACK.Flow.Selector
Permits selection.of Pack Flow according.to number.of passengers and.ambient conditions.
Zone.Temperature.Selectors
Adjust Temperature.for.associated.Zone.
HOT.AIR.Switch
.  
ON.-.Automatically.controls zone.Hot Air pressure.regulating.valve.

.  
OFF.-.Closes.Hot.Air.pressure regulating.valve and.trim.air.valves and.resets fault.circuit.

.  
Fault.Light.-.Illuminates amber.when duct overheat.is detected..If this occurs,.the.zone.Hot.Air pressure regulating.valve and.trim.air.valves automatically.close. The FAULT.light stay.on.until.;power.temperature.is sensed with.the.switch.off.

.
PACK.1/2.Switches

.  
ON.-.Automatically.controls.Pack.Flow control valve. Valve.regulates.flow, except.in the.following.conditions:

.  
Upstream pressure.is below minimum