Miller Electric NT 450, NT 500 manual Operation, Controls

SECTION 5 − OPERATION

5-1. Controls

2

3 6

5

4 7 1

229 448-A

1 Power Switch

.This unit is equipped with a fan motor that

is thermostatically controlled and only runs when cooling is needed.

2Voltmeter (see Section 5-2)

3Ammeter (see Section 5-2)

4Mode Switch

Use Mode switch to determine both process and output On/Off control. Orange areas highlight “contactor on” positions.

5 Panel/Remote Control Switch

For front panel control, place switch in Panel position and use the V/A Adjust control to set amperage or voltage, depending on Mode switch selection.

For remote control, make connections to Re- mote 14 receptacle (see Section 4-11), and place switch in Remote position. In TIG modes, output available through the remote control is a percent of the V/A Adjust control setting. Value selected on V/A Adjust control

is maximum output available through the re- mote control. In the MIG, CC, and V-Sense feeder modes, a remote control provides full range of unit output regardless of V/A Adjust control setting. A remote control is not func- tional in Air-Carbon Arc or Stick modes. If connection to Remote 14 receptacle is re- moved and Panel/Remote control switch re- mains in Remote position, output is controlled with the V/A Adjust control.

6 V/A (Voltage/Amperage) Adjust Control

With Mode switch in any Stick or TIG position, use control to adjust amperage from 5 to 500 amps. With Mode switch in a V-Sense Feeder or MIG position, use control to adjust voltage from 10 to 38 volts.

7 Inductance/Dig Control

Control adjusts Dig when a Stick or CC mode is selected on mode switch. When set to- wards minimum, short-circuit amperage at low arc voltage is the same as normal welding amperage. When set to max, control in- creases short-circuit amperage at low arc

voltage. This allows the operator to use a very short arc length without sticking the electrode. As control is adjusted, the amount of Dig selected is displayed on the amps me- ter as a percentage (0 to 100%) of full range, and dig is displayed on the volts meter.

When Air-Carbon Arc mode is selected, Dig is internally set to max.

Control adjusts inductance when MIG or V- Sense Feeder position is selected on mode switch. Inductance determines the “wetness” of the weld puddle. As setting is increased to- wards maximum, “wetness” (puddle fluidity) increases. As control is adjusted, the amount of inductance selected is displayed on the amps meter as a percentage (0 to 100%) of full range, and ind is displayed on the volts meter.

This control is not functional when one of the TIG modes is selected.

Change control setting to best suite application.

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