Miller Electric Big Blue 400P Welding System User Manual


 
OM-4421 Page 44
9-8. Overload Protection
803 605
2
1
9
8
7
4
Y Stop engine.
. When a supplementary protector,
circuit breaker or fuse opens, it usu-
ally indicates a more serious problem
exists. Contact Factory Authorized
Service Agent.
1 Fuse F1
2 Fuse F2
F1 and F2 protect the stator exciter wind-
ing from overload. If F1 opens, weld and
generator power is low or stops entirely.
If F2 opens, weld output is low or stops
entirely. 4 kVA/kW generator power is still
available.
3 Circuit Breaker CB4 (Not Shown)
4 Supplementary Protector CB5
(CC/CV Models Only)
5 Supplementary Protector CB6
(CC/CV Models Only)
6 Circuit Breaker CB10 (Not Shown)
7 Supplementary Protector CB11
8 Supplementary Protector CB12
9 Supplementary Protector CB13
10 Circuit Breaker CB14 (Not Shown)
CB4 protects the welding arc drive (dig)
circuit. If CB4 opens, electrode may stick
to the workpiece more frequently during
low voltage (short arc length) conditions.
CB4 automatically resets when the fault
is corrected.
CB5 protects the 24 volt ac output to re-
mote receptacle RC14, and 24 volt output
to field current regulator board PC1 (CC/
CV models only). If CB5 opens, weld out-
put and 24 volt output to RC14 stops. On
units with optional three-phase genera-
tor, generator power output at receptacle
RC5 also stops if CB5 opens.
CB6 protects the 115 volt ac output to re-
mote 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 weld control circuit. 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 Section
6-2). If CB11 opens on CV models, weld
output stops (generator power is still
available).
CB12 protects the field flashing circuit. If
CB12 opens, the generator may not ex-
cite at start-up and weld and generator
power output may not be available.
CB13 protects the engine control circuit.
If CB13 opens, the engine does not
crank.
CB14 protects throttle solenoid TS1 on
units with auto idle option. If CB14 opens,
the engine does not run at idle speed.
CB14 automatically resets when the fault
is corrected.
Press button to reset supplementary pro-
tector.
5