Thermal Arc ARCMASTER 300 MST Operating Manual page 26

3. Positive Terminal
Welding current flows from the Power Source via heavy duty Dinse type terminal. It is essential,
however, that the male plug is inserted and turned securely to achieve a sound electrical connection.
Negative Terminal
4.
Welding current flows from the Power Source via heavy duty Dinse type terminal. It is essential,
however, that the male plug is inserted and turned securely to achieve a sound electrical connection.
Loose welding terminal connections can cause overheating and result in the male plug being
fused in the bayonet terminal and /or melting of the housing (case).
5. Remote Control Socket
The 19 pin Remote Control Socket is used to connect remote current control devices to the welding
Power Source. To make connections, align keyway, insert plug, and rotate threaded collar fully clockwise.
Socket Pin
A
B
C
D
E
G
H
J
K
J
L
M
N
P
R
S
T
U
V
CAUTION 2
Contactor circuit (+15 Volts)
Contactor circuit in, (closure between pin A and Pin B will energize output.)
Scaled output voltage signal: Vfb = 10 Arc Volts/Volt
24 VAC auxiliary power high side
115 VAC auxiliary power high side
Chassis ground
Remote control maximum
Remote control wiper (0 – 10 Volts)
Remote Control minimum
Remote control wiper (0 – 10 Volts)
Control circuit common
Arc Establish = +12 Volts
Control Circuit common
24 VAC auxiliary power high side
24/115 VAC neutral
N/C
N/C
Scaled output signal: Ifb = 100 Amps/Volt
N/C
20
Function