Machine Protection; Thermal Protection; Protective Circuits; Over Current Protection - Lincoln Electric POWER WAVE S500 Service Manual

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THERMAL PROTECTION

Three normally closed (NC) thermostats protect the
machine from excessive operating temperatures. Two
thermostats are located on the 115VAC heat sink and
protect the 115VAC Inverter board from over-heating.
The third thermostat is located and integrated into the
Six Phase Chopper and is monitored by the Digital
Control board. Excessive temperatures may be
caused by a lack of cooling air or by operating the
machine beyond its duty cycle or output rating.
excessive operating temperatures should occur, the
thermostats will prevent output from the machine. The
yellow thermal light, located on the front of the
machine, will be illuminated. The thermostats are self-
resetting once the machine cools sufficiently. If the
thermostat shutdown was caused by excessive output
or duty cycle and the fans are operating normally, the
power switch may be left on and the reset should occur
within a 15-minute period. If the fans are not turning or
the intake air louvers are obstructed, the power must
be removed from the machine and the fan condition or
air obstruction corrected.
THEORY OF OPERATION

MACHINE PROTECTION

PROTECTIVE CIRCUITS

Protective circuits are designed into the Power Wave
S500 to sense trouble and shut down the machine
before damage occurs to the machineʼs internal com-
ponents. Error Codes will be flashed out by the light on
the front of the machine and will help identify the rea-
son for the shutdown. Fault codes can also be seen by
using the Diagnostic Software.
located on the PC boards aid in determining compo-
If nent status and diagnosing problems.
Troubleshooting section for more information regard-
ing Error Codes.

OVER CURRENT PROTECTION

If the machineʼs welding output is shorted the Digital
Control board will limit the current to 375 amps.
POWER WAVE ® S500
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®
Various status lights
See the