HEADQUARTERS OH-58A, Technical Manual

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TM 55-1520-228-10
Figure 2-18. Electrical System Schematic (Sheet 2 of 2)
2-50. ALTERNATING CURRENT POWER
SUPPLY.
The OH-58A/C helicopter is equipped with a solid state
inverter powered from the non-essential 28 volt DC bus
through a 5 ampere INV PWR circuit breaker and is
manually controlled by an INV switch (figure 2-12). The
inverter delivers 115 volt AC 400 Hz to the 115 volt AC
bus. A caution panel segment INST INVERTER will
illuminate when AC power is lost.
a. Controls . The AC power is controlled by the INV
switch and AC circuit breakers. The inverter switch is
located in the overhead console and is a two-position
toggle switch labeled INV and OFF. AC electrical power
is provided to the electrical system when the switch is in
the forward position. DC power to the inverter is
supplied by the non-essential bus; therefore, to have AC
power, electrical power must be available at the non-
essential bus. When the switch is in the OFF position it
opens the circuit to the inverter.
b. Circuit Breakers . The AC circuit breakers are
on the aft end of the overhead console. In the event of a
circuit overload, the circuit breaker protecting that circuit
will pop out. The circuit is reactivated by pushing in the
circuit breaker button.
2-42 Change 10