AC Power System - P-8610065

STUDENT GUIDE FOR T-1A AIRCRAFT SYSTEMS

CHAPTER SIX

DC Voltmeter

The DC voltmeter placarded VOLTS, is located in the overhead switch panel. The voltmeter

displays the DC voltage supplied by either the right or left generator or the battery.

604. AC POWER SYSTEM

The AC power system supplies AC power required by various aircraft systems.

AC Power Components

Two inverters located in the nose compartment supply AC power.

Static Inverters

Two static inverters, No. 1 and No. 2, supply 115 and 26 Volts Alternating Current (VAC), 400

Hz, single-phase electrical power at an apparent power rating of 250 volt-amperes each.

AC Power Distribution

AC power is distributed through three 115 and three 26 VAC buses. The AC buses are the only

sources of AC electrical power for those systems requiring supplemental AC power.

AC Power Distribution Control

An inverter selector switch is located in the main circuit breaker panel. The switch is placarded

INV SEL, with its switch positions labeled NO. 1, AUTO, and NO. 2. The switch is normally in

the guarded AUTO position. In this position, the No. 1 inverter supplies power to the primary

buses and the No. 2 inverter supplies power to the secondary buses.

Placing the inverter selector switch in the NO. 1 position forces the No. 1 inverter to power the

primary buses by bypassing their fault sensing circuits. Placing the inverter selector switch in

the NO. 2 position causes the inverters to trade functions so the No. 2 inverter powers the

primary buses and the No. 1 inverter powers the secondary buses.

AC Voltmeter

An AC voltmeter is located on the aft circuit breaker panel adjacent to the rotary AC voltmeter

selector switch. The meter indicates the voltage of one of the four sources of AC power as

selected by the selector switch to confirm inverter operational status.

605. ELECTRICAL POWER SYSTEM LIMITATIONS

Refer to Instrument Markings, Section V, T.O. 1T-1A-1, for specific limitations of the various

components of the electrical power supply system.

ELECTRICAL POWER SYSTEMS

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