Miller Electric Big Blue 402P Welding System User Manual


 
OM-491 Page 41Return To Table Of Contents
9-7. Overload Protection
802 170-E
21
9
8
7
4
Y Stop engine.
. When a circuit breaker or fuse
opens, it usually indicates a
more serious problem exists.
Contact Factory Authorized
Service Agent.
1 Fuse F1
2 Fuse F2
F1 and F2 protect the stator exciter
winding from overload. If F1 opens,
weld and generator power is low or
stops entirely. If F2 opens, weld out-
put is low or stops entirely. 4 kVA/
kW generator power is still avail-
able.
3 Circuit Breaker CB4 (Not
Shown)
4 Circuit Breaker CB5
(CC/CV Models Only)
5 Circuit Breaker CB6
(CC/CV Models Only)
6 Circuit Breaker CB10 (Not
Shown)
7 Circuit Breaker CB11
8 Circuit Breaker CB12
9 Circuit Breaker CB13
CB4 protects the welding arc drive
(dig) circuit. If CB4 opens, electro-
de may stick to the workpiece more
frequently during low voltage (short
arc length) conditions. CB4 auto-
matically resets when the fault is
corrected.
CB5 protects the 24 volt ac output
to remote receptacle RC14, and 24
volt output to field current regulator
board PC1 (CC/CV models only). If
CB5 opens, weld output and 24 volt
output to RC14 stops. On units with
optional three−phase generator,
output at receptacle RC5 also stops
if CB5 opens.
CB6 protects the 115 volt ac output
to remote receptacle RC14 (CC/CV
models only). If CB6 opens, 115 volt
output to RC14 stops.
CB10 protects the engine battery
circuit. If CB10 opens, the engine
will not crank. CB10 automatically
resets when the fault is corrected.
CB11 protects the engine wiring
harness. On CC models, if CB11
opens the max OCV circuit does
not work and open circuit voltage is
variable at all times (see max OCV
note under Weld Controls in Sec-
tion 6-2). If CB11 opens on CV mod-
els, weld output stops (generator
power is still available).
CB12 protects the field flashing cir-
cuit. If CB12 opens, the generator
may not excite at start-up and weld
and generator power output may
not be available.
CB13 protects the engine shut-
down circuit. If CB13 opens, the en-
gine cranks but does not start.
Press button to reset breaker.
5