Lincoln Electric IM409 IDEALARC R3R-400 - Manual (Page 16)

D-4 TROUBLESHOOTING D-4
IDEALARC® R3R, -300, -400, -500
Observe all Safety Guidelines detailed througout this manual
If for any reason you do not understand the test procedures or are unable to perform the tests/repairs safely, contact your Local
Lincoln Authorized Field Service Facility for technical troubleshooting assistance before you proceed.
CAUTION
FUNCTION PROBLEMS
PROBLEMS
(SYMPTOMS)
POSSIBLE
CAUSE
RECOMMENDED
COURSE OF ACTION
Machine does not have maximum
output (67 to 71 volts).
Machine comes on but soon trips
off while under load and High
Temperature Warning Light glows.
(Thermostat tripped)
Machine comes on but reduces to
low output under load and remains
there until the load is broken and
arc re-started. See Fault Protection
Operation Section.
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 over-
load protection on control board
to operate.
2. Machine output shorted causing
overload protection on control
board to operate.
3. Control circuit defective.
If all recommended possible areas
of misadjustment have been
checked and the problem persists,
Contact your local Lincoln
Authorized Field Service Facility.