TUBE ASSEM. 4V1200 - Caterpillar

VR6 Regulator
Refer to the Specifications, Systems Operation, Testing and Adjusting, RENR2480, "VR6 Voltage Regulator".Factory calibration (12) is used by the technicians. The following procedure can be used if the factory calibration has been disturbed:
Open up the factory calibration adjustment (12) .
Start the genset.
Run the genset at no load.
Turn the factory calibration adjustment (12) in a counterclockwise direction.
Turn the potentiometer for voltage adjustment (13) in a clockwise direction.
Slowly turn the factory calibration adjustment (12) in a clockwise direction. For 60 Hz applications, continue to turn the adjustment until the generator voltage is 272 1 VAC. For 50 Hz applications, continue to turn the adjustment until the generator voltage is 226 1 VAC.
Turn the potentiometer for voltage adjustment (13) counterclockwise.
Verify that the generator voltage is between 156 VAC and 180 VAC. The unit is calibrated.
Seal the factory calibration adjustment (12) . VR4 Regulator
Note: The VR4 regulator is protected by a fuse(s). The VR4 regulator also has solid state overcurrent protection. If a replaced fuse fails, contact your Caterpillar dealer.
Remove the access panel of the generator.
Turn the potentiometer for voltage gain (3) counterclockwise to zero. Then, turn the potentiometer for voltage gain (3) to about 1/4 of full range of clockwise travel.
Perform required maintenance on the engine before you start the engine.
Start the engine. Allow the engine to warm up. Refer to Safety Section, "Engine Starting".
Increase engine speed to full governed rated speed (high idle).
Observe the voltmeter reading. If the desired voltage is not indicated, set no load voltage with the voltage level potentiometer (2) or the voltage adjust rheostat. The voltage adjust rheostat is located on the control panel.
Close the load circuit breaker. Apply full load gradually. Adjust the governor control until the correct frequency is on the frequency meter or until the rated speed is displayed on the tachometer. The unit of measurement for frequency is Hertz. The unit of measurement for the rated speed is RPM.Note: The value for the frequency can be found on the nameplate.
After you apply the full load, and if voltmeter reading increases turn the potentiometer for voltage gain (3) counterclockwise in order to obtain the same voltage with no load. Refer to step 6 for the voltage at no load. After you apply the full load, and if the voltmeter reading decreases, turn the gain potentiometer (3) slightly in the clockwise direction.
Remove the load. If necessary, adjust the voltage level potentiometer (2) in order to obtain desired voltage.
Reapply the load. Observe the voltmeter reading. Repeat steps 7 through 9 until the voltage at no load equals the voltage at full load.
Tighten the locknuts. Install the protective screws on the respective potentiometers. Install the access panel of the generator.Digital Voltage Regulator (DVR)
Refer to the Specifications, Systems Operation, Testing and Adjusting, SENR5833, "Digital Voltage Regulator".The digital voltage regulator (DVR) can be set up for a specific application by using the configurable parameters. Parameters are preset at the factory. Parameters may need to be adjusted in order to meet the specific requirements of