BOLT-LOCKING 5K7138 - Caterpillar

Excitation circuit "E+", and "E-" must not be left open when the machine is running and the available power inputs "X1", "X2", "Z1", and "Z2" are connected to the Automatic Voltage Regulator (AVR). Damage will occur to the AVR under these conditions. Remove the power input to the AVR when the "E+" and "E-" are disconnected from the AVR.
The battery that is used for testing must be isolated from the system ground.
Test Step 1. Verify that all of the wiring is properly connected. Refer to Systems Operation, KENR9008, "Wiring Diagram" that is located in this manual.Results:
OK - The wiring connections are correct. Proceed to Step 2.
Not OK - The wiring is improperly connected or the wiring is loose.Repair: Reconnect the wiring properly.STOPTest Step 2. Verify that the generator is running at rated speed.Results:
OK - The generator is running at rated speed. Proceed to Step 3.
Not OK - The generator is not running at rated speed. .Repair: Increase the speed of the generator to the rated value.STOPTest Step 3. Verify that the residual voltage that is applied to the power input terminals and to "X1", "X2", "Z1", and "Z2" is 60 VAC or higher.Results:
OK - If the voltage is 60 VAC or higher, then go to Step 4.
Not OK - The applied voltage is less than 60 VAC.Repair: Refer to the Service Manual, KENR8205, "Electrical Power Generation LC Series Generators". Follow the procedure to troubleshoot and repair a failed PMG or AREP. STOPTest Step 4. Verify that the fuse "F1" is not open. Results:
OK - If the fuse "F1" is not open, proceed to Step 5.
Not OK - The fuse is open.Repair: Replace the fuse.STOPTest Step 5. AREP Excited Generators OnlyFlash the exciter stator with a 6 VDC battery or a 12 VDC battery. Connect the positive terminal of the battery to "E+" and the negative terminal of the battery to "E-" for 2 to 3 seconds when the engine is stopped. Restart the generator set and check the output voltage.Results:
OK - There was a lack of residual magnetism.STOP
Not OK - The generator has a voltage output, but the voltage does not reach the rated value. Proceed to Step 6.
Not OK - The generator does not have output voltage when the generator starts. Proceed to Step 7.Test Step 6. Shut off the generator set. Check the diodes. Refer to the Service Manual, KENR8205, "Rotating Rectifier - Test". Follow the procedure to test the rotating rectifier.Results:
OK - The diodes are good. Go to the Step 7.
Not OK - The diodes are bad.Repair: Repair the rotating rectifier or replace the rotating rectifier.STOPTest Step 7. Shut off the generator set. Check the exciter stator and the rotor for a short circuit. Measure the circuit resistances. Refer to Service Manual, KENR8205, "Winding - Test" and follow the procedure for testing the winding.Results:
OK - The windings are good. Proceed to the Step 8.
Not OK - The windings are bad.Repair: Repair the windings.STOPTest Step 8. Shut off the generator set. Check the main stator