In Mma, Difficulty Striking The Arc, Welding Irregular - Cebora POWER ROD 1565 Cell Service Manual

CEBORA S.p.A.

3.3.8 - In MMA, difficulty striking the arc, welding irregular.

The power source art. 255 offers the functions HOT-START, to assist striking the arc in both
MMA and TIG modes, and ARC-FORCE, to maximize transferring the electrode drop to the
ARC-FORCE AND HOT-START REFERENCES TEST.
The ARC-FORCE function is timed (maximum duration = 400 msec.) and begins when the
output voltage, during MMA welding, exceeds a certain threshold (not adjustable). Therefore,
for the following test we recommend temporarily setting up a jumper on terminals 8 and 3 of
the connector (H), to prevents the output voltage from being generated and thus stabilizing the
welding test condition. Without the jumper on the connector (H), the test voltage may be
measured only during the initial "lamp-test" and the subsequent 400 msec, or during MMA
welding.
ARC-FORCE FUNCTION REFERENCE. Power board (11), connector CN1, terminals 4 (+)
and 1 (-) = voltage adjustable from 0 to maximum (approximately +4 Vdc), using the knob
(L), with open-circuit power source.
HOT-START FUNCTION REFERENCE. Power board (11), connector CN1, terminals 8 (+)
and 1 (-) = voltage adjustable from 0 to maximum (approximately +4 Vdc) using the knob (I),
with open-circuit power source.
♦ Check the wiring between CN1 power board (11) and CN1 panel board (16).
♦ Check the supply voltages for the panel board (16), performing the PANEL
BOARD (16) POWER SUPPLY TEST, in par. 3.3.1, if necessary.
♦ With the power source off, temporarily disconnect connector CN1 on power board
(11) and check the resistance between terminals 8 and 1 and between terminals 4
and 1 of CN1 on power board (11). Correct value = approximately 200 Kohm for
both measurements. If 0 ohm (short-circuit) o >Mohm (circuit broken), check the
resistive network RR2 and its connection with CN1 terminals 8 and 4, or replace
the power board (11).
♦ Make sure that the potentiometers PT1 and PT3 on panel board (16) are intact.
Replace if defective, or replace the panel board (16).
♦ Replace the power board (11).
3.302.113
NOTE
workpiece in MMA welding.
NOTE
Correct?
YES
NO
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20/11/02