Selco Genesis 240 - Stage 3: As above.; Stage 4: Weld in TIG (lift) or select MMA...

126 Diagnosis procedure
Take the following measurements (values @ 400 V line voltage):
Board Connector Cables Value
15.14.233 CN3 52-50 = 400 Vac
yes
: go on ; no : after disconnecting the machine from the mains power supply, check the continuity of the tracks on
board 15.14.233 (see drawing)
- between V and cable no.52
- between U and cable no.50
yes
: go on ; no : replace board 15.14.233
Board Connector Cables Value
15.14.233 CN3 53-53 = 230 Vac
yes
: go on ; no :
- check correct connection of cables 53 (x two), 17 and 18
- replace auxiliary transformer 05.11.259
Board Connector Cables Value
15.14.254 CN1 17-18 = 230 Vac
yes
: go on ; no :
- check fuse F2 on board 15.14.233
- check correct connection of cables 17 and 18
With the master switch open, reconnect CN1 of board 15.14.254.
Close the master switch and measure again
Board Connector Cables Value
15.14.254 CN1 17-18 = 230 Vac
yes
: go on ; no : replace board 15.14.254 (and fuse F2 if necessary)
With the master switch open, reconnect CN1 of board 15.14.233.
Close the master switch and check operation of the fan (presence of air flow from back to front of machine).
yes
: go on ; no : check connection of fan or replace it
Stage 3 : As above
Front panel selector in TIG (lift) mode
Checks :
Check:
GREEN led on front panel = ON
yes
: go on ; no : perform power supplies checking procedure
With a tester set to Vdc, check between points:
b-bb = 565Vdc @ 400Vac (=Vin X 2 )
yes
: go on ; no : check the condition of the tracks on board 15.14.233
Perform power inverter checking procedure and quit the procedure checking that cables no.22 and no.23 are connected
to board 15.14.254 and that the short circuit created by means of a wire between TP6 and TP3 has been eliminated.
(Important! Red cable to screw + and black cable to screw -).
Stage 4 : Weld in TIG (lift) or select MMA operating mode from front panel and apply load 3 + 8.
Set 120 A via front panel potentiometer.
Checks :
With the shunt on the ground cable and a tester set to mVdc, measure the current delivered:
I = 120 A
yes
: go on ; no : perform current adjustment circuits checking procedure.