Auxiliary Power In Ms - Receptacle; Overload, Overcurrent And Fault Protection - Lincoln Electric SVM188-A Service Manual

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3. OUTPUT CONTROL
This control provides continuous control of the
machine's output voltage and current from minimum
to maximum (typical full pot range between 15 to 44
volts and 90 to 750 amps) as it is rotated clock-wise.
Voltage or current control is determined by setting
of Mode Switch (CV or CC).
4. OUTPUT TERMINALS ON/REMOTE Switch
When this switch is in the REMOTE "
tion, the DC-600's output terminals will be electri-
cally "cold" until a remote device such as a wire
feeder closes the #2 and #4 circuit in the MS-recep-
tacle or terminal strip (T.S.2). When this switch is in
the ON " " position the machine's output termi-
nals will be electrically energized all the time.
5. LOCAL/REMOTE Switch
When this switch is set to the LOCAL "
control of the output voltage and current is via the
OUTPUT CONTROL on the DC-600's control panel.
When this switch is set to the REMOTE
position, control is through a remote source such as
a wire feeder via the #75, #76, and #77 leads in the
MS-receptacle or terminal strip (T.S.1).
6. Mode Switch
This switch allows for selecting the welding process
to be used:
CC STICK-for SMAW and AAC
CV SUBMERGED ARC- for SAW
CV INNERSHIELD- for FCAW and GMAW
7. 115VAC Duplex Receptacle (60 Hertz Models)
This receptacle provides up to 15 amps of 115 VAC
auxiliary power.
8. 115VAC 15 Amp Circuit Breaker
This breaker protects the 115 VAC auxiliary circuits
located in the duplex receptacle, terminal strip
(T.S.2) and MS-receptacle.
9. 42VAC 10 Amp Circuit Breaker
This breaker protects the 42VAC auxiliary circuits
located in the terminal strip (T.S.2) and MS-recep-
tacle.
10.14 Pin MS-Receptacle
This connector provides easy connection for a wire
feeder control cable. It provides connections for
auxiliary power, output switching, remote output
control, wire feeder voltmeter sense lead and
ground. Refer to 14 Pin MS Type Receptacle in the
Installation Section for information about the circuits
made available at this receptacle.
OPERATION
11.Terminal Strip Cover Panel
Rotate this panel to gain access to the circuits made
available at the two terminal strips (T.S.1 and T.S.2).
These terminal strips contains the same circuits as
the 14 pin MS-receptacle. There is a box connector
adjacent to this cover for routing leads to the termi-
nal strips.
12.Negative Output Terminal
" posi-
This output terminal is for connecting a welding
cable. To change welding polarity and for proper
welding cable size refer to Electrode and Work
Cables in the Installation Section.
13.Positive Output Terminal
This output terminal is for connecting a welding
cable. To change welding polarity and for proper
welding cable size refer to Electrode and Work
" position,
Cables in the Installation Section.
AUXILIARY POWER IN MS-RECEPTACLE
" "
42 volt AC auxiliary power, as required for some wire
feeders, is available through the wire feeder MS-recep-
tacle. A 10 amp circuit breaker protects the 42 volt cir-
cuit from overloads.
DC-600 machines can also supply 115 volt AC auxil-
iary power through the wire feeder receptacle. A 15
amp circuit breaker protects the 115 volt circuit from
overloads.
OVERLOAD, OVERCURRENT, AND
FAULT PROTECTION
This welder has thermostatic protection from excessive
duty cycles, overloads, loss of cooling, and high ambi-
ent temperatures. When the welder is subjected to an
overload or loss of cooling, a thermostat will open. The
input contactor will open and remain open until the
machine cools; the white POWER light stays illuminat-
ed. No welding is possible during this cool down peri-
od. The machine will reset automatically when the ther-
mostat cools.
The power source is also protected against overcur-
rents in the SCR bridge assembly through an electron-
ic protection circuit. This circuit senses currents over
780 amps on the power source and opens the input
contactor should the overcurrent remain for a predeter-
mined time (the white POWER light stays illuminated).
The predetermined time varies with the amount of
overcurrent; the greater the overcurrent, the shorter
the time. The input contactor will remain open until the
power source is manually started by resetting the
POWER ON/OFF toggle switch.
DC-600
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