3.2.6
The wire feeder motor does not work.
The wire feeder motor (12) speed regulation circuits
are fed from the power transformer TF5 secondary
winding, so when the inverter is operating (see Fig.
2.3.1). Therefore, during the threading operation
be careful do not put in contact the torch or welding
wire with the ground potential (welding bench or
WIRE FEEDER MOTOR (12) TEST.
□ Panel board (19), connector J5, terminals 4(+) and 3(-)
= +17 Vdc approximately, three seconds after pressing
the start button (threading speed whatever the welding
program selected).
NO
EN
♦ Check the wiring between J5 panel board
(19) and wire feeder motor (12).
♦ With the power source off, temporarily dis-
connect the wire feeder motor (12) terminals
from connector J5 on panel board (19) and
make sure the resistance between the motor
terminals left free. Correct value = approxi-
mately 1.2 ohm (motor winding resistance).
If >Mohm (winding interrupted), replace
wire feeder motor (12).
♦ Make sure there are no mechanical impedi-
ments blocking the motor (12).
♦ Check the motor rotation direction. If incorrect,
reverse the wires on connector J5.
♦ Replace the wire feeder motor (12) and/or
panel board (19).
MOTOR POWER SUPPLY TEST.
□ Panel board (19), connector J6, terminals 2(+) and 1(-)
= +40 Vdc approximately, with power source powered;
+50 Vdc approximately, with start button pressed.
YES
♦ Check wiring between J6 panel board (19),
J1 supply board (40) and J9 power board (34).
♦ With J1, J2 and J3 on supply board (40)
connected, with the power source off,
temporarily disconnect J9 from power board
(34). Power up the power source and make sure
on J6 of panel board (19), terminals 2(+) and
1(-), voltage = +40 Vdc approx., with power
source powered at nominal mains voltage.
24
WARNING
workpiece).
Correct?
YES
Correct?
NO
♦ With J9 on power board (34) connected,
with the power source off, temporarily dis-
connect J2 and J3 from supply board (40).
Power up the power source and make sure on
J6 of panel board (19), terminals 2(+) and 1(-),
voltage = +50 Vdc approximately, with start
button pressed.
If not correct:
− check the inverter operation performing,
if necessary, the OPEN CIRCUIT OUT-
PUT VOLTAGE TEST, par. 3.2.7;
− make sure efficiency of the diode D30,
capacitor C40 and power transformer TF5
on power board (34) (see Fig. 2.3.1);
− replace power board (34).
If correct, identify defective components on
panel board (19), based on the Connectors
map of par. 5.5 and replace them.
♦ Replace power (34) and/or supply (40) and/or
panel (19) boards.
SPEED FEED-BACK SIGNAL TEST.
□ Panel board (19), connector J2, terminals 2(+) - 4(-) =
terminals 3(+) - 4(-) = Fig. 5.2.1, three seconds after
pressing the start button (speed feed-back signal from
motor encoder).
NO
Correct?
♦ Regular operation.
■ Check the wiring between J5 panel board (19) and wire
feeder motor (12).
■ Make sure there are no mechanical impediments
blocking the motor (12).
■ Check the motor rotation direction. If incorrect, reverse
the wires on connector J5.
■ With the power source off, temporarily disconnect
the wire feeder motor (12) terminals from connector
J5 on panel board (19) and make sure the resistance
between the motor terminals left free. Correct value =
approximately 1.2 ohm (motor winding resistance). If 0
ohm (short circuit) replace wire feeder motor (12) and
check integrity of mosfet M2, M3, resistors R50, R51,
R52, R53 and diodes D8 and D9 on panel board (19)
(see Connectors map, par. 5.5).
■ Replace the wire feeder motor (12) and/or supply (40)
and /or panel (19) boards.
YES
3302327/A