Operation Manual

BASLER MODEL AVC63-4 VOLTAGE REGULATOR

IMPORTANT: The exciter field DC resistance must be 15 Ohms or higher and less than 100 Ohms.

If the exciter field DC resistance is less than 15 Ohms and the full load field current does not exceed the

maximum continuous current rating of the controller, a resistor of ample wattage must be added in series

with the field to increase the total resistance to 15 Ohms.

FREQUENCY COMPENSATION:

The frequency compensation feature improves system load pickup performance by restraining voltage

recovery until the frequency has also started to recover. The corner frequency range is set for 50 Hz or

60 Hz by connecting the Corner Frequency Jumper to the appropriate terminal. The corner frequency

setting is adjusted by the Underfrequency Control potentiometer. Clockwise rotation increases the

corner frequency and Counterclockwise rotation decreases the corner frequency. (Current Version)

OVEREXCITATION SHUTDOWN:

The overexcitation shutdown feature removes controller output power, after a time delay, if the exciter

field voltage exceeds 100V DC, ±5%. The time delay is inversely proportional to the magnitude of the

detected overvoltage – up to 135V DC. Beyond 140V DC, the field voltage is removed after

approximately two seconds. Once the output power is removed, the controller can be reset by decreasing

the input voltage to less than 10V AC for two seconds, minimum. This can be achieved by stopping the

prime mover or by interrupting the controller input power with a reset switch.

SYSTEM START-UP:

Start engine, allow a few minutes to warm-up to operating temperature and rated speed. Generator

voltage should build up. If the voltage does not build up it may be necessary to Field Flash the

generator. (See section on Field Flashing) Slowly adjust the controller’s voltage control potentiometer

until the generator voltage reaches the nominal level. Apply and remove the generator load to verify

stability. If the generator responds too slowly or hunts (oscillates) adjust the controller’s stability control

with no load applied. Also check the stability of the governor system (mechanical or electronic) if

applicable. Next check the regulation under normal operating conditions. If not acceptable, check the

engine speed. Be sure to use an average-sensing voltmeter not an RMS-sensing voltmeter and should be

connected at the same point as the controller sensing. Verify the corner frequency setting by slowly

reducing the generator frequency until the generator output voltage just starts to decrease. If adjustment

of the corner frequency is required, (Current Version) rotate the underfrequency control fully

counterclockwise. Reduce the generator frequency from nominal (either 50Hz or 60 Hz) to the desired

corner frequency. Slowly adjust the underfrequency control clockwise until the generator output voltage

just starts to decrease.