ESAB 653 cvcc, Instruction Manual

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Table 6-2. Troubleshooting Guide
CONDITION ACTION
Unit Inoperative A. No input power. Check main line (user’s) switch fuses — replace if needed.
B. Poor or improper input (terminal board) connections.
C. Defective on/off switch — replace.
D. Thermal light on. Main transformer overheating. Also check for proper cooling,
proper primary hookup, or shorted turn on secondary.
E. Thermal light on. Fan motor not operating — check motor and leads.
F. External Ground Conductor fault indicator ”ON”. - Check for cause and correct.
Turn power switch ”OFF” then ”ON” to reset.
G. Loss of primary phase. Check that LED on control PCB is not lit. If lit, find & replace
defective fuse.
No Output — Fan Running A. Poor or improper electrical input — check input connections on TB.
B. Poor connections at output terminals/work station — check, tighten or replace.
C. Main transformer overheating — thermal switches tripped due to restricted cool-
ing air. Temperature light on front panel will be lit. Let unit cool down.
D. PC board defective or loose PC board connector(s) — if loose, reinsert; if defective,
replace.
Limited Output or
Low Open-Circuit Voltage
A. Input voltage jumper links on terminal board improperly set — check for proper
voltage.
B. Poor output connections. Take apart, clean, and tighten securely.
C. Panel-Remote switch in Remote position and remote voltage pot disabled.
D. Over current condition had occurred. Unit is in “fold back” mode. See Section
4.1.6.
Erratic Weld Current A. Welding cable size too small — use correct cables.
B. Loose welding cable connection (will usually get hot) — tighten connections.
C. Improper wire feeder setup.
D. Defective SCR in bridge rectifier.
E. PC board defective — replace.
High Output, No Voltage Control A. PC board defective or loose — reset and/or replace board.
No 115 Volt ac Output A. Circuit breaker tripped. Check 115V CB2 — Reset.
Line Fuse Blows When Power
Source is First Turned On
A. Shorted SCR in Main Bridge — replace.
B. Shorted capacitor in Capacitor Bank.
Wire Feeder is Inoperative A. Loose feeder control cable — Check and tighten all connections.
B. A Circuit Breaker tripped — Check 42V CB1 and 115V CB2 — Reset.
SECTION 6 TROUBLESHOOTING