Lincoln Electric RANGER 305 D Service Manual page 113

RANGER 305D
ST TOR SHORT CIRCUIT & GROUND TEST (continued)
CONTACTOR
CONTROL
REMOTE
CONTROL
TEST PROCEDURE
1. Perform Case Cover Removal Procedure.
Perform Capacitor Discharge Procedure.
2.
3. Unplug anything that may be connected to the
auxiliary receptacles or the 14 pin amphenol.
4. Disconnect and isolate GND-E lead from the bottom
ground screw inside the left case front. See
control Inner-Connection diagram. See Figure F.14.
5. Disconnect the #7 and #9 leads from the field
bridge rectifier. See Wiring Diagram.
6. Using an ohmmeter, check the resistance between
chassis ground and each of the following points;
Resistance should read very high, 500,000 (500K)
ohms minimum.
1) Pin 1 at the 14 pin amphenol, and the #5 lead
that had been disconnected from the ground
screw. (this checks for a connection between
the wire feed winding and the auxiliary winding.)
2) Pin 1 of the 14 pin amphenol and lead #7 or #9.
(This checks for a connection between the wire
feed winding and the exciter winding.)
3) Pin 1 of the 14 pin amphenol an lead W1, W2, or
W3. (This checks for a connection between the
wire feed winding and the weld winding).
4) Lead #5 and lead #7 or #9. (This checks for a
connection between the auxiliary winding and
the weld winding). See Wiring Diagram.
5) Lead #5 and lead W1, W2, or W3. (This checks
for a connection the auxiliary winding and the
weld winding.) See Wiring Diagram.
6) Lead #7 or #9 and lead W1, W2, or W3. (This
FIGURE F.14 – WELD CONTROL BO RD
AMPHENOL 1
C
B
A
D
L
K
J
E
M
N
I
F
G
H
KEY
L4
2 TIMES THRU FERRITE
LEADS 75A, 76A, & 77A
If any of the above readings is less than 500,000 (500k)
ohms, check for damaged, contaminated, or shorted wiring or
components between the test points and the stator winding.
If necessary, disconnect and isolate the stator leads as close
to the stator winding as possible. See wiring diagram. If the
low resistance is determined to be between the windings
within the stator, the stator is defective and should be
replaced*.
* NOTE: The field bridge rectifier and field capacitor may
appear to function normally when tested independently.
But may malfunctions when placed under the stress of
normal operation. For this reason, It is recommended
that the bridge rectifier and capacitor be replaced with
known good components before replacing the stator.
F 56
TROUBLESHOOTING & REPAIR
GROUND
120 VAC FOR WIRE FEEDER
40 VAC FOR WIRE FEEDER
21 WORK SENSE
checks for a connection between the exciter
winding and the weld winding.) See Wiring
Diagram.