Troubleshooting - Miller Big Blue 500 Pro Owner's Manual

8-13. Troubleshooting

.
Also see Voltmeter/Ammeter error displays to assist in troubleshooting weld problems (see Section 8-12). Also see Engine Information Display
to assist in troubleshooting engine related problems (see Section 11).
A. Welding
Trouble
No weld output; generator power output
okay at AC receptacles.
No weld output or generator power out-
put at AC receptacles.
Erratic weld output.
High weld output.
Low weld output.
Low open-circuit voltage.
No remote fine amperage or voltage
control.
Constant speed wire feeder does not
work.
Low CV weld output.
Min or max CV weld output only.
.
Complete Parts List available at www.MillerWelds.com
Place Process/Contactor switch in an Electrode Hot position, or place switch in a Remote On/Off Re-
quired position and connect remote contactor to Remote receptacle (see Section 5-9).
Reset supplementary protector CB3 (see Section 8-11).
Reset supplementary protector CB9 (see Section 8-11). Check for faulty remote device connected to
Remote receptacle.
Check and secure connections to Remote receptacle (see Section 5-9).
Check fuse F2, and replace if open (see Section 8-11). Have Factory Authorized Service Agent check
brushes and slip rings, weld excitation circuit, and the rotor.
Disconnect equipment from generator power receptacles during start-up.
Reset supplementary protector CB4 (see Section 8-11).
Check fuses F1 and F2, and replace if open (see Section 8-11). Have Factory Authorized Service Agent
check integrated rectifier SR2, capacitor C6, and the rotor.
Have Factory Authorized Service Agent check brushes and slip rings, and field excitation circuit.
Check and tighten connections inside and outside unit.
Be sure connection to work piece is clean and tight.
Use dry, properly stored electrodes.
Remove excessive coils from weld cables.
Have Factory Authorized Service Agent check brushes and slip rings.
Check position of Voltage/Amperage Adjust control.
Have Factory Authorized Service Agent check voltage feedback circuit.
Check position of Voltage/Amperage Adjust control.
Check fuses F1 and F2, and replace if open (see Section 8-11). Have Factory Authorized Service Agent
check integrated rectifier SR2, capacitor C6, and the rotor.
Check position of Process/Contactor switch.
Check and secure connections to Remote receptacle (see Section 5-9).
Repair or replace remote control device.
Have Factory Authorized Service Agent check current sensing devices, and connections.
Reset supplementary protector CB9 (see Section 8-11).
Check and secure connections to Remote receptacle (see Section 5-9).
Repair or replace wire feeder.
Increase Voltage/Amperage Adjust Control setting.
Check position of Voltage/Amperage Adjust control and Process/Contactor switch.
Repair or replace remote control device.
Have Factory Authorized Service Agent check Amperage/Voltage Adjust Control and field current
regulator board.
Remedy
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