Lincoln Electric IDEALARC R3R 500-I Operating Manual page 15

PROBLEMS
(SYMPTOMS)
E. Machine does not have maximum
output (67 to 71 volts).
F Machine comes on but soon trips off
while under load and High Temperature
Warning Light glows. (Thermostat
tripped)
G Machine comes on but reduces to low
output under load and remains there
until the load is broken and arc
restarted. See Fault Protection
Troubleshooting Page ?.
IM 6000
TROUBLESHOOTING
POSSIBLE
CAUSE
FUNCTION PROBLEMS
1. Input fuse blown. Machine is single
phased.
2. One phase of main transformer
windings open.
3. Defective power bridge.
1. Improper ventilation.
2. Loaded beyond rating.
3. Fan inoperative.
4. Shorted diode or SCR in power rectifier
bridge.
1. Excessive load causing the overload
protection on control board to operate.
2. Machine output shorted causing
overload protection on control board to
operate.
3. Control circuit defective.
Idealarc R3R 500-I & 600-I
RECOMMENDED
COURSE OF ACTION
1. Replace fuse or repair input line.
Check reason for fault.
2. Repair.
3. Check bridge per Troubleshooting
Procedures Page ? and check snubber
per Page ?.
1. Make sure all case openings are free
for proper circulation of air.
2. Operate at rated current and duty cycle.
3. Check leads and motor bearings. Fan
can be tested on 115 volt line.
4. Refer to Troubleshooting Procedures
Page ? and Snubber, Page ?
1. Reduce load.
2. Turn machine off and remove short.
3. Replace per PC board,
Troubleshooting, Page ?.
Page 15