Lincoln Electric IM669 RED-D-ARC DC-600 - Manual (Page 22)

DC-600 RED-D-ARC
B-7 OPERATION B-7
SEMI-AUTOMATIC AND
AUTOMATIC WIRE FEEDING WITH
THE DC-600 AND WIRE FEEDERS
When using the DC-600 with semi-automatic or auto-
matic wire feeding equipment and for stick welding or
air/carbon arc cutting, it is recommended that the
optional MULTI-PROCESS SWITCH be used. This
switch permits you to easily change the polarity of the
connected wire feeding equipment or switch to stick
welding or air/carbon arc cutting.
NA-3 AUTOMATIC WIRE FEEDER
1. Set the DC-600 LOCAL/REMOTE Switch to
REMOTE. Set the OUTPUT TERMINALS switch
to REMOTE. NOTE: Later model NA-3 automatic
wire feeders are capable of cold starts when the
NA-3 Mode switch is in the CV or CC mode posi-
tion. Some earlier models are capable of cold
starting only in the CC mode position. Cold start-
ing enables you to inch the wire down to the work,
automatically stop, and automatically energize the
flux hopper valve.
2. Set the DC-600 welding mode switch for the
desired process: CV SUBMERGED ARC, CV
INNERSHIELD mode or CC STICK mode.
3. Set the NA-3 mode Switch Position to either CV or
CC to match the DC-600 mode selected in step 2.
4. Refer to the NA-3 operators manual for instruc-
tions on how to use the NA-3 in conjunction with
the DC-600.
5. Follow the following guidelines for good arc strik-
ing detailed below for each welding mode.
GOOD ARC STRIKING GUIDELINES FOR THE NA-
3 WITH THE DC-600 IN THE CV INNERSHIELD, CV
SUBMERGED ARC OR CC STICK WELDING
MODES.
Following are some basic arc striking techniques that
apply to all wire feed processes. Using these proce-
dures should provide trouble-free starting. These pro-
cedures apply to single, solid wires and Innershield
wires.
1. Cut the electrode to a sharp point.
2. Set the NA-3 Open Circuit Voltage Control to the
same dial setting as the Arc Voltage Control. If
this is a new welding procedure, a good starting
point is to set the Open Circuit Voltage Control to
# 6.
NOTE: The open circuit voltage of the
DC-600 varies from approximately 16 volts to 56
volts in the CV INNERSHIELD
or CV
SUBMERGED ARC modes. The open circuit volt-
age is constant in the CC STICK mode.
3. Run a test weld. Set proper current, voltage, and
travel speed.
a. For the best starting performance, the NA-
3 Open Circuit Voltage Control and Voltage
Control setting should be the same. Set the
Inch Speed Control for the slowest inch
speed possible.
b. To adjust the Open Circuit Voltage Control to
get the best starting performance, make
repeated starts observing the NA-3 voltmeter.
When the voltmeter pointer swings smoothly up to
the desired arc voltage, without undershooting or
overshooting the desired arc voltage, the Open
Circuit Voltage Control is set properly.
If the voltmeter pointer overshoots the desired
voltage and then returns back to the desired volt-
age, the Open Circuit Voltage Control is set too
high. This can result in a bad start where the wire
tends to "Blast off."
If the voltmeter pointer hesitates before coming up
to the desired voltage, the Open Circuit Voltage
Control is set too low. This can cause the elec-
trode to stub.
4. Start and make the weld.
a. Cold starts. For cold starts, be sure the work
piece is clean and the electrode makes posi-
tive contact with the work piece.
b. Hot "On the Fly" starts. For hot starts, travel
should begin before the wire contacts the
work piece.