Miller Electric Big 40G Description Of Front Panel Controls See Section, Ampere Range Switch

5-2. Description Of Front Panel Controls (See Section 5-1)

.This unit has a max OCV control circuit that resets Amperage/Voltage Adjust Control R1 to maximum when the arc breaks. When an arc is struck, weld out- put control returns to the R1 front panel or combination front panel/remote control setting. The Amperage/Voltage Adjust control adjusts amperage only when constant current (CC) welding and does not adjust open-circuit voltage. The max OCV control circuit does not function when constant voltage (CV) welding (optional).

1 Ampere Range Switch

YDo not switch under load.

Use switch to select weld amperage range. For most welding applications, use lowest am- perage range possible to help prevent arc out- ages. When using MIG (CV) mode (optional), place switch in maximum position.

2 Amperage/Voltage Adjust Control

Control adjusts amperage within range se- lected by Ampere Range switch. Weld output would be 148 A DC with controls set as shown (50% of 85 to 210 A).

3Amperage/Voltage Adjust Switch (Optional)

Use switch to select front panel or remote am- perage control (see Section 5-3).

For front panel control, place switch in Panel position. For remote control, place switch in Remote position and connect remote control to Remote 14 receptacle RC3 or terminal strip 3T.

4Output (Electrode) Control Switch (Optional)

Use switch to control remote contactor con-

nected to receptacle RC3 or terminal strip 3T (see Sections 4-7 and 4-8).

YWeld output terminals are energized when Output (Electrode) switch is On (Hot) and engine is running.

For weld output, place switch in the On (Hot) position. Open-circuit voltage is present at the weld output terminals whenever engine is run- ning.

For remote output control, place switch in Re- mote position. Open-circuit voltage is present at the weld output terminals when remote con- tactor switch is closed.

5 Process Switch (Optional)

Use switch to select Stick or MIG (CV) weld output. Use Stick for Stick (SMAW) welding. Use MIG (CV) for wire feed processes (MIG, FCAW). If using MIG (CV), place Ampere Range switch in maximum position. To en- sure wire feeder reliability and improve arc starting, unit does not run at idle speed when operated in MIG (CV) mode.

.Place Process switch in Stick position when using optional auxiliary power plant.

6DC Voltmeter (Optional)

7DC Ammeter (Optional)

8Magnetic Shutdown Switch

Use switch during start-up to bypass engine shutdown system. System stops engine if oil pressure is too low or coolant temperature is too high.

9 Choke Control

Use choke to change engine air-fuel mix.

10 Engine Control Switch

Use switch to start engine, select engine speed, and stop engine.

In Run position, engine runs at weld/power speed. In Run/Idle position, engine runs at idle speed at no load and weld speed with load ap- plied. Turn to run position if using optional aux- iliary power plant.

To Start: Pull choke out. Turn Engine Control switch to Start while pressing Shutdown switch. Release Engine Control switch when engine starts, then release Shutdown switch and push choke in.

.If the engine does not start, let engine come to a complete stop before attempt- ing restart.

To Stop: turn Engine Control switch to Off position.

11Engine Hour Meter

12Polarity And AC Selector Switch (Optional)

YDo not switch under load.

13Battery Charging Warning Light Light goes on if battery is not charging.

14Low Oil Pressure/High Engine Tempera- ture Warning Light

Light goes on if oil pressure is low or coolant temperature is high.

YStop engine and fix trouble if either warning light goes on.

15Fuel Gauge

16Engine Temperature Gauge (Optional)

Normal temperature is 180 - 200° F (81 - 93° C). Stop engine if temperature exceeds 240° F (116° C).

17 Engine Oil Pressure Gauge (Optional)

Normal pressure is 40 psi (276 kPa). Stop en- gine if pressure is below 8 psi (55 kPa).

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