RPM
HERTZ
A–C AMPERES
A–C VOLTS
Voltage
UPPER SCALE
L2–L3
L2
L1–L2
L1
Volts
Amps
L1–L2
L2
L3–L2
L3
L1–L0
None
Off
Off
L1–L2
L2
Three Phase
Single Phase
Field
Breaker
PUSH FOR
ETHER INJECTION
LOWER SCALE
8
7
6
4
5
3
2
1
TM 9-4940-568-10
2-7
Figure 2-2. Generator Set AC Instrument Panel Controls and Indicators.
Key
Control or Indicator
Function
1
AC Voltmeter
Dual range instrument indicating AC voltage.
2
AC Ammeter
Dual range instrument indicates AC generator line current.
3
Frequency/RPM Meter
Indicates generator output frequency in hertz and engine
speed in revolutions–per–minute (RPM).
4
Voltage Adjusting Rheostat
Provides approximately plus or minus five percent
adjustment of the rated output voltage.
5
Upper and Lower Scale
Indicator Lamps
Indicates which scale to use on the AC voltmeter and
ammeter.
6
Phase Selector Switch
Selects phases of generator output to be measured by
AC voltmeter and ammeter.
7
Field Breaker
Provides over-current protection.
8
Ether Start
Injects ether into the engine intake manifold for cold weather
starting.
