ARMY TM 9-6115-670-14&P
1-21
1.17.
GENERATOR OPERATION.
1.17.1. Generator Circuit. The AC generator is a self-excited, single-bearing, brushless, drip-proof, two
pole generator which outputs 120/240 VAC at 60 Hz when driven at 3600 rpm. It consists of an
excitation system (including exciter stator, exciter rotor, and main rectifier assembly), and a generator
system (including main stator and main rotor).
1.17.2. Main Stator and Automatic Voltage Regulator (AVR) Interface. The main stator provides
power for excitation of the exciter field through the AVR (the controlling device governing the level of
excitation provided to the exciter field) (Figure 1-9). The AVR responds to a voltage sensing signal
derived from the main stator winding. By controlling the low power of the exciter field, control of the high
power requirement of the main field is achieved through the rectified output of the exciter armature.
1.17.3. AVR and Diesel Engine Interface. The AVR detects engine speed and provides voltage fall off
with speed, below a pre-selected speed (Hz). This prevents over-excitation at low engine speeds and
softens the effect of load switching to relieve the burden on the engine.
Figure 1-9. Main Stator and AVR Interface
