Troubleshooting Tables - Miller Big Blue 302D Owner's Manual

8-9. Troubleshooting Tables

A. Welding − CC Models
Trouble
No weld output; auxiliary power output
okay.
No weld output or auxiliary power output. Disconnect equipment from auxiliary power receptacles during start-up.
Erratic weld output.
High weld output.
Low weld output.
Low open-circuit voltage.
Maximum weld output only in each
ampere range (with Stick/TIG Selection
switch in Stick position).
No remote fine amperage control.
Check position of Ampere Range switch.
Check position of optional polarity switch.
Place Amperage Adjust switch in Panel position, or place switch in Remote position and connect remote
control to Remote Amperage Adjust receptacle RC13 (see Sections 4-10 and 5-1).
Check and secure connections to Remote Amperage Adjust receptacle RC13 (see Section 4-10).
Check fuse F2, and replace if open (see Section 8-7). Have Factory Authorized Service Agent check inte-
grated rectifier SR2 and the rotor.
Have Factory Authorized Service Agent check brushes and slip rings, and field excitation circuit.
Check fuses F1 and F2, and replace if open (see Section 8-7). Have Factory Authorized Service Agent
check integrated rectifier SR1, capacitor C9, integrated rectifier SR2, and the rotor.
Reset circuit breaker CB12. Have Factory Authorized Service Agent check diode D1 (see Section 8-7).
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.
Check engine weld/power speed, and adjust if necessary (see Section 8-5).
Have Factory Authorized Service Agent check OCV control circuit.
Check engine weld/power speed, and adjust if necessary (see Section 8-5).
Check fuses F1 and F2, and replace if open (see Section 8-7). Have Factory Authorized Service Agent
check integrated rectifier SR1, capacitor C9, integrated rectifier SR2, and the rotor.
Check engine weld/power speed, and adjust if necessary (see Section 8-5).
Have Factory Authorized Service Agent check control relay CR7.
Place Amperage Adjust switch in correct position.
Check and secure connections to Remote Amperage Adjust receptacle RC13 (see Section 4-10).
Repair or replace remote control device.
Reset circuit breaker CB11 (see Section 8-7). Have Factory Authorized Service Agent check control relay
CR7.
Have Factory Authorized Service Agent check OCV control circuit.
Have Factory Authorized Service Agent check control relay CR7.
Remedy
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