Miller Multimatic 255 Owner's Manual page 63

Message
Thermal error-Boost module thermis-
tor is shorted.
Thermal error-Boost module thermis-
tor open.
Thermal error-Inverter module ther-
mistor is shorted.
Thermal error-Inverter module ther-
mistor open.
Thermal error-Secondary magnetics
thermistor is shorted.
Thermal error-Secondary magnetics
thermistor is open.
Thermal error-Output rectifier thermis-
tor is shorted.
Thermal error-Output rectifier thermis-
tor is open.
Boost Error
Cycle power to clear error
*Vbus Top High *Vbus Bottom High
*Vbus Balance *Precharge *Initial
Boost Check *Current Sensor 1 *Over
Current *Precharge Relay Failure
Cycle power to clear error +15V or –
15V * Primary Error *Boost Error *In-
verter Error
Over voltage-Cycle power to clear.
Under voltage-Cycle power to clear.
Network error-Inverter Communication
is down.
Network error-Primary Communica-
tion is down.
Network error-Communication be-
tween UI and control boards is down.
Stuck Electrode
Stuck Tungsten
�
Complete Parts List is available at www.MillerWelds.com
Error
The control board is damaged.
The boost module thermistor is reading too high
for a valid temperature.
The control board is damaged.
Ambient temperature is too cold for valid
reading.
The boost module thermistor is reading too low
for a valid temperature.
The control board is damaged.
The inverter module thermistor is reading too
high for a valid temperature.
The control board is damaged.
Ambient temperature is too cold for valid
reading.
The inverter module thermistor is reading too low
for a valid temperature.
The control board is damaged.
The secondary magnetics thermistor is reading
too low for a valid temperature.
The control board is damaged.
Ambient temperature is too cold for valid
reading.
The secondary magnetics thermistor is
unplugged.
The secondary magnetics thermistor is reading
too high for a valid temperature.
The control board is damaged.
The output rectifier thermistor is reading too high
for a valid temperature.
The control board is damaged.
Ambient temperature is too cold for valid
reading.
The output rectifier thermistor is unplugged.
The output rectifier thermistor is reading too low
for a valid temperature..
The control board is damaged.
The primary boost has not successfully been
established.
Primary voltage is above 690 volts.
The primary voltage is below 150 volts.
The two microcontrollers on the control board
are no longer communicating.
The wiring harness between the control board
and interface board is damaged.
The primary control board is damaged.
The interface board is damaged.
Stick welding electrode has become stuck in
weld puddle and turned output off.
Tungsten electrode has become stuck in weld
puddle and turned output off.
Remedy
Contact Miller Electric authorized service
location
Place unit in environment warmer than –30°F (–
22°C).
Contact Miller Electric authorized service
location.
Contact Miller Electric authorized service
location
Place unit in environment warmer than –30°F (–
22°C).
Contact Miller Electric authorized service
location.
Contact Miller Electric authorized service
location
Place unit in environment warmer than –30°F (–
22°C).
Contact Miller Electric authorized service
location.
Contact Miller Electric authorized service
location
Place unit in environment warmer than –30°F (–
22°C).
Contact Miller Electric authorized service
location.
Cycle power to clear error. If this error persists
after a power cycle, contact Miller Electric Mfg.
authorized service location.
Reduce primary voltage below 690 volts.
Increase primary voltage above 150 volts.
Cycle power to clear error. If this error persists
after a power cycle, contact Miller Electric Mfg.
authorized service location.
Contact Miller Electric Mfg. authorized service
location.
Remove Stick electrode from workpiece and out-
put will turn back on after about one second.
Remove the tungsten from workpiece and output
will turn back on after about one second.
OM-278174 Page 59