Lincoln Electric INVERTEC V300-PRO SVM105-B Service Manual page 56

F-26
TEST PROCEDURE
1. Disconnect power to the machine and perform
Input Filter Capacitor Discharge Procedure as
described in Section F.
2. Disconnect all wiring harness leads (401/403, 1/8,
9, 12, 4/5, 402/404) from the Switch Boards.
3. Fold the leads up so they do not interfere with the
exposed PC board terminals. See Figure F.8.
TROUBLESHOOTING & REPAIR
SWITCH BOARD TEST (cont.)
FIGURE F.8 - SWITCH BOARD RESISTANCE TEST
V300-IPRO
4. Using an ohmmeter, perform the Resistance Tests
detailed in Table F.2 and Table F.3. If any test fails,
replace both Switch Boards. See Switch Board
replacement procedure.
5. If the Switch Boards appear to be burned or over-
heated, or if the machine was supplied by a 380
VAC or higher voltage supply when the failure
occurred, replace the Capacitors and the Switch
Boards.
F-26