Lincoln Electric Idealarc DC600 9773MSP Service Manual page 23

B-8
ARC STRIKING WITH IDEALARC 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 strik-
ing.
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.
a. Set the Start Board current control to 1 1/2 dial
numbers below that set on the NA-3 current
control.
b. Set the Start Board voltage control equal with
the NA-3 voltage control setting.
NOTE: These Start Board current and voltage set-
tings result in a start up current that is lower than
the NA-3 current setting and approximately equal
with the NA-3 voltage setting for the desired weld-
ing procedure.
IDEALARC DC-600
OPERATION
6. Establish the correct arc striking procedure with
the NA-3 Start Board timer set at maximum.
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 volt-
age and then returns back to the desired voltage,
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.
c. Set NA-3 Start Board current and voltage as
close to the welding procedure current and
voltage as possible.
NOTE:
should be as close as possible to the welding pro-
cedure current and voltage, while still getting satis-
factory starts.
d. Set the start time to as low a time as possible
while still getting satisfactory starts.
7. Start and make the weld.
The Start Board current and voltage