Lincoln Electric IDEALARC R3R 500-I Operating Manual page 16

PROBLEMS
(SYMPTOMS)
H. Machine trips off when under no load or
makes excessive noise like it is loaded.
I. Variable or sluggish welding arc.
J. Welder will not shut off.
K. Current control on machine not
functioning.
Page 16
TROUBLESHOOTING
POSSIBLE
CAUSE
FUNCTION PROBLEMS
1. Power bridge rectifier may have a
shorted diode or SCR.
2. Short in the transformer.
3. Fan hitting vertical baffle.
1. Poor work or electrode cable
connection.
2. Current too low.
3. Welding leads too small.
4. Open SCR or diode in power rectifier
bridge.
5. Control circuit problems.
1. Input contactor contacts frozen.
1. Current control switch in wrong position.
2. Current control switch defective.
3. Current control potentiometer defective.
4. Lead or connection in control circuit
open.
5. Defective control or circuit boards.
Idealarc R3R 500-I & 600-I
RECOMMENDED
COURSE OF ACTION
1. Refer to Power Hybrid, Troubleshooting
Procedures, Page ? and Snubber, Page
?.
2. Repair.
3. Clear the fan.
1. Check and clean cable connections.
2. Check recommended currents for rod
type and size.
3. See Table in Output Connection Section.
4. Check per Power Rectifier Bridge
Troubleshooting Procedures, Page ?
and Snubber, Page ?.
5. See SCR Troubleshooting, Page ?.
1. Replace input contactor.
1. Place switch in "machine" ( I ) position.
2. Check per Page ?.
3. Check per Page ?.
4. Repair or connect.
5. See SCR Troubleshooting, Page ?..
IM 6000