Section 3 - Operation; Controls - Miller Electric Shopmaster 300 AC/DC Owner's Manual

3-1. Controls

7
1 Arc Force (Dig) Control
For SMAW, control increases short-circuit
amperage which allows the operator to use
a very short arc length without sticking the
electrode.
Set control at 0 for GTAW. When set at 0
(zero), short circuit amperage at low arc
voltage is the same as normal welding
amperage.
2 Amperage/Voltage Adjustment Control
For AC or DC CC welding, such as GTAW
and SMAW welding, adjust control accord-
ing to amperage (A) scale. For GMAW and
FCAW welding, adjust control according to
SECTION 3 – OPERATION
4
6 9
voltage (V) scale.
3 Power Switch
4 Output Selector Switch
5 Amperage/Voltage Control Switch
Switch selects front panel or remote
amperage/voltage control.
For remote amperage/voltage control, front
panel control setting is the maximum output
available. For example: If front panel control
is set to 200 A, the range available at the
remote amperage control is 0 to 200 A.
6 Output (Contactor) Switch
Switch selects front panel or remote output
control.
8 5 2 3 1
Y Weld output terminals are energized
when Output (Contactor) switch is
On and Power is On.
7 Remote 14 Receptacle (See
Section 2-7)
8 Circuit Breaker CB1
If CB1 opens, 115 volts ac output to the 115
volts ac duplex receptacle and Remote 14
receptacle stops. Press button to reset
breaker.
9 Circuit Breaker CB2
If CB2 opens, 24 volts ac output to the
Remote 14 receptacle stops. Press button to
reset breaker.
Ref. 202 556-A
OM-322 Page 15