Miller Electric 75 Welder User Manual


 
OM-228 956 Page 31
7-2. Diagnostics (Continued)
RMD DONE
The RMD done message indicates the
RMD demo is completed. Pressing
Jog/Purge button will change the screen to
CYCL PWR on the display. Turn unit power
off and back on again.
OVER AVER
The over average error indicates that
current is outside the average range for the
set program parameters. Check and correct
program parameters. Press Jog/Purge
button to clear error.
UNIT COMM
The unit communication error indicates
the data bus on the PCM board is not
functioning properly. Press Jog/Purge
button to clear error.
REL TRIG
The release trigger error indicates the
user held the gun trigger after a timed weld
was completed causing the contactor to
remain on. Press Jog/Purge button to clear
error.
TRIG STUK
The trigger stuck error indicates the user
held the gun trigger during power up. Press
Jog/Purge button to clear error.
ERR UNKN
The unknown error indicates a
malfunction in the system somewhere.
Press Jog/Purge button to clear error.
UNIT
COMM
ERR
UNKN
Indicates a CRC
PCM bus error.
Indicates an
unknown error.
RMD
DONE
OVER
AVER
Indicates RMD
demo is done.
Indicates an over
average current error.
REL
TRIG
Indicates a contactor
on error.
TRIG
STUK
Indicates a trigger
closed error.
7-3. Troubleshooting
Y Disconnect power before troubleshooting
Trouble Remedy
Wire feeds, shielding gas flows, but
electrode wire is not energized.
Check and secure weld cable connections (see Section 4-2).
Electrode wire feeding stops or feeds
erratically during welding
Check gun trigger connection. See gun Owner’s Manual.
erratically during welding.
Check gun trigger. See gun Owner’s Manual.
Readjust hub tension and drive roll pressure (see Section 4-9).
Change to correct size drive roll (see Table 9-1).
Clean or replace dirty or worn drive roll.
Incorrect size or worn wire guides.
Replace contact tip or liner. See gun Owner’s Manual.
Remove weld spatter or foreign matter from around nozzle opening.
Have Factory Authorized Service Agency check drive motor or motor control board PC1.
Motor runs slowly. Check for correct input voltage.
Wire feeder power is on, displays light
up, but unit is inoperative.
Check welding gun trigger leads for continuity, and repair leads or replace gun.