Lincoln Electric IDEALARC DC-1500 Service Manual page 19

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3. Remove the blue jumper lead connected between #1 on
the coil of the main relay and #7 on the coil of the trans-
fer relay. (The main relay is the upper right relay when
facing the left end of the control box. The transfer relay is
just to the left of the main relay.)
4. Replace the LAF-3 control cover.
5. Set the "POS — NEG" switch (on both the NL Option and
the DC-1500) to correspond to the polarity of the elec-
trode cable connection.
6. Set the mode switch on the front of the DC-1500 to
"Variable Voltage".
7. Set the toggle switch on the front of the DC-1500 to
"Output Control Remote".
8. Set the DC-1500 welding current as required by the pro-
cedures using the K775 Remote Output Control shipped
with the NL Option.
9. Set the LAF-3 "Inch Speed" control near minimum so the
electrode touches the work lightly before starting the arc.
The NL Option "Inch Speed" control is not in the circuit.
10. Set the "Hot Start Control" on the NL Option at #2. This
setting does not change the open circuit voltage, but it will
improve starting, particularly at low currents. Adjust the
control for optimum starting.
OPERATION
NOTE: The "Hot Start Control" does not affect the start-
ing method of the LAF-3, i.e., "cold" start, "hot" start, etc.
See IM-198-B, Sec. 2.4.9.
11. Set the NL Option "Contactor Drop-Out Delay" switch to
"On". This circuit delays opening of the output contactor
for a fixed length of time after wire feeding stops to pre-
vent sticking.
Operation When Connected to the LT-3 or LT-34
(OBSOLETE FEATURE)
Follow the same instructions as above except in Step 1, con-
nect per M13322. Omit Steps 2, 3 and 4. Set the "Inch
Speed" control on the NL Option as low as possible so the
electrode touches the work piece lightly before starting the
arc.
Overload Protection
The NL Option kit includes two fuses on the front panel. The
upper fuse (2 amp slow blow) protects the inching circuit
when the option is used with LT-3 and LT-34 wire feeders.
The lower fuse (2.8 amp slow blow) protects the 115 volt DC
circuit (#1 and #2). If replacing either fuse use the same size
and type.
IDEALARC® DC-1500
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