Section 9 − Troubleshooting - Miller Big Blue 800 Owner's Manual

SECTION 9 − TROUBLESHOOTING
9-1. Troubleshooting Tables
A. Welding
Trouble
No weld output; generator power output
okay at ac receptacles.
No weld output or generator power
output.
Erratic weld output.
High weld output.
Voltage/Amperage control does not
work when welding in Stick mode.
Low weld output.
Electrode sticks to the workpiece more
frequently during low voltage (short arc
length) conditions.
Low open-circuit voltage.
Place Process/Contactor switch in a Weld Terminals Always On position, or place switch in a Remote
position and connect remote contactor to Remote 14 receptacle RC14 (see Sections 5-13 and 6-1).
Check position of Ampere Range switch.
Reset supplementary protector CB11 (see Section 8-9).
Reset supplementary protector CB5 (see Section 8-9). Check for faulty remote device connected to
RC14.
Check and secure connections to Remote 14 receptacle RC14 (see Section 5-13).
Have Factory Authorized Service Agent check connector board PC6 and connections.
Check fuse F2, and replace if open (see Section 8-9). Have Factory Authorized Service Agent check
brushes and slip rings, field excitation circuit, field current regulator board PC1, and the rotor.
Disconnect equipment from generator power receptacles during start-up.
Check fuses F1 and F2, and replace if open (see Section 8-9). Have Factory Authorized Service Agent
check integrated rectifier SR1, capacitor C9, field current regulator board PC1, and the rotor.
Reset supplementary protector CB12 (see Section 8-9).
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 Ampere Range switch and Voltage/Amperage Adjust control.
Engine speed may need adjustment. Contact engine manufacturer's Factory Authorized Service
Agent.
Have Factory Authorized Service Agent check field current regulator board PC1.
Place Ampere Range switch in lower range. Voltage/Amperage control does not work with Ampere
Range switch in highest range.
Check position of Ampere Range switch and Voltage/Amperage Adjust control.
Engine speed may need adjustment. Contact engine manufacturer's Factory Authorized Service
Agent.
Check fuses F1 and F2, and replace if open (see Section 8-9). Have Factory Authorized Service Agent
check integrated rectifier SR1, capacitor C9, field current regulator board PC1, and the rotor.
Circuit breaker CB4 may be open. CB4 automatically resets when the fault is corrected (see Section 8-9).
Have Factory Authorized Service Agent check transformer T1 and integrated rectifiers SR4 and SR5.
Engine speed may need adjustment. Contact engine manufacturer's Factory Authorized Service Agent.
Check position of Process/Contactor switch.
Remedy
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