Na-3 Automatic Wire Feeder - Lincoln Electric DC-600 series Operator's Manual

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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.
• For the best starting performance, the NA-3 Open
Circuit Voltage Control and Voltage Control set-
ting should be the same. Set the Inch Speed
Control for the slowest inch speed possible.
OPERATION
• 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.
• Cold starts. For cold starts, be sure the work
piece is clean and the electrode makes posi t i v e
contact with the work piece.
• Hot "On the Fly" starts. For hot starts, travel
should begin before the wire contacts the work
piece.
ARC STRIKING WITH DC-600 AND THE NA-3
START BOARD
When electrical strikeouts exceed 1 3/4" (44.4mm) an
NA-3 Start Board may be required to improve arc
striking.
When the NA-3 Start Board is used to improve arc
striking, use the following procedures:
1. Set start time at 0.
2. Set NA-3 start current and start voltage at mid-
range.
3. Set the NA-3 output current and voltage to the
proper settings for the welding procedure to be
used.
4. Turn the Start Board Timer to maximum.
5. Set Start Board current and voltage control.
• Set the Start Board current control to 1 1/2 dial
numbers below that set on the NA-3 current control.
• Set the Start Board voltage control equal with the
NA-3 voltage control setting.
DC-600
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