Lincoln LT-7, Руководство по устранению неисправностей

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TROUBLESHOOTING AND REPAIR
B-25 B-25
LT-7 TRACTOR
1. Remove the wire feed motor connector
from the LT7 control box.
2. Using the ohmmeter measure the motor
resistances per Table B.3. Also see
Figure B.4
3. If the motor resistance test is good pro-
ceed to the Motor Applied Voltage Test.
MOTOR APPLIED VOLTAGE TEST
1. Carefully connect the 110VDC supply
(SUPPLY TURNED OFF) to pins C and D
on the motor connector.
2. Carefully connect the variable 0 to 90VDC
supply (SUPPLY TURNED OFF) to pins A
and B on the motor connector.(See Table
B.3)
3. Apply field voltage first(pins C and D) to
the motor. Then slowly apply the arma-
ture voltage on pins A and B.(See Table
B.3)
4. The motor should run and the speed
should vary with changes to the armature
voltage.
5. If the motor does NOT run and change
speed correctly the motor or gear box
may be faulty.
6. To stop motor REMOVE ARMATURE
VOLTAGE FIRST. (Pins A and B)
TEST POINTS RESISTANCE DC VOLTAGE
Lead #539 to #541 4 to 5 ohms 0 to 90VDC
Armature
Lead #626 to #627 750 to 850 ohms 90 to 120VDC
Field Winding
All leads 500,000 ohms min. NONE
to
motor shell
TABLE B.3
TEST PROCEDURE
WIRE DRIVE MOTOR TEST ( continued)
FIGURE B.4 - Wire Drive Motor Connector Pins
A
B
C
D
E
#539
#541
#626
#627