Lincoln Electric POWER MIG SVM160-B Service Manual page 88

F-44
CHOPPER BOARD ASSEMBLY REMOVAL
REMOVAL PROCEDURE
WARNING
ELECTRIC SHOCK can kill.
High voltage is present when input power is applied to
the machine.
NOTE: Cut cable ties as needed to improve access.
See Figure F.14 for the following procedure.
1. Disconnect main input power from the machine.
2. Perform the Chopper Board Capacitor Discharge
Procedure.
3. Remove the case side panels using a 3/8 in. nut-
driver.
4. Label and disconnect thermostat leads 503 and
503A.
5. Unplug J99 from the chopper board.
TROUBLESHOOTING & REPAIR
AND REPLACEMENT (continued)
FIGURE F.14 – CHOPPER BOARD ASSEMBLY DETAILS
9
4
6
Leads B8 & B7
(other side of chopper board)
POWER MIG 300
12
8
10
7
6. Disconnect lead 607 from terminal B8 and lead 613
from terminal B7 at their in-line connectors.
7. Using a 7/16 in. wrench, remove heavy lead B8 (to
negative output terminal) and B2 (to choke) from
the chopper board.
8. Using a 7/16 in. wrench, remove heavy leads B1
and B5 (to output rectifier) from the chopper board.
9. Using the 5/16 in. nutdriver, remove the 4 screws
holding the fan baffle to the machine base. This
will allow you to move the baffle back out of the
way to access the right rear nut on the chopper
assembly bracket.
10. Using the 3/8 in. wrench or nutdriver, remove the 4
nuts holding the chopper assembly brackets to the
machine base.
11. Carefully remove the chopper assembly from the
machine.
12. Using a 7/16 in. wrench, remove the 2 support
brackets from the chopper board assembly.
F-44
23D
12