737 Flight Crew Operations Manual
Electrical -
Controls and Indicators
Boeing Proprietary. Copyright © Boeing. May be subject to export restrictions under EAR. See title page for details.
D6-27370-866-EGP 6.10.3
4 Frequency Meter
Indicates frequency of source selected by AC meters selector.
5 AC Voltmeter
Indicates voltage of source selected by AC meters selector.
6 Battery Discharge (BAT DISCHARGE) Light
Illuminated (amber) – with BAT switch ON, excessive battery discharge detected.
7 TR UNIT Light
Illuminated (amber) –
• on the ground – any TR has failed.
• in flight –
• TR1 failed; or
• TR2 and TR3 failed.
8 Electrical (ELEC) Light
Illuminated (amber) – a fault exists in DC power system or standby power system.
Note: Operates only with airplane on ground.
9 Maintenance Test (MAINT) Switch
Used by maintenance.
10 DC Meters Selector
Selects DC source for DC voltmeter and DC ammeter indications.
TEST – used by maintenance.
11 Battery (BAT) Switch
OFF –
• removes power from battery bus and switched hot battery bus when
operating with normal power sources available
• removes power from battery bus, switched hot battery bus, DC standby
bus, static inverter, and AC standby bus when battery is only power
source.
ON (guarded position) –
• provides power to switched hot battery bus
• energizes relays to provide automatic switching of standby electrical
system to battery power with loss of normal power.
September 28, 2006
To Next Page
Loading...
