Miller Electric Big Blue 500 X, Big Blue 400P manual Overload Protection

9-8. Overload Protection

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YStop engine.

.When a supplementary protector,

circuit breaker or fuse opens, it usu- ally indicates a more serious problem exists. Contact Factory Authorized Service Agent.

1Fuse F1

2Fuse 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.

3Circuit Breaker CB4 (Not Shown)

4Supplementary Protector CB5 (CC/CV Models Only)

5Supplementary Protector CB6 (CC/CV Models Only)

6Circuit Breaker CB10 (Not Shown)

7Supplementary Protector CB11

8Supplementary Protector CB12

9Supplementary Protector CB13

10Circuit 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

CCmodels, 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.

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