Service manual

S0740 800 179/E071123/P64
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ct33f3soft
8. Disconnect connector 15XS3 (supply to the fan) from terminal E of circuit board 2AP1.
Connect the 24 V DC input of the SST 1 to terminal E of circuit board 2AP1.
9. Connect the 24 V DC output of the SST 1 to terminals N1 and N2 of power board
15AP1.
Circuit connections and measuring points for soft starting
10. Switch on the machine and set it to MMA mode.
11. Check that the DC voltage across smoothing capacitor 15C1 is 22--24 V.
12. Check that the DC voltage at the input of AC power board 18AP2 is about 6--7 V.
13. Check that the DC voltage at the welding terminals is about 5-- 6 V.
14. If all the measurements are as described above, reconnect the wires to restore the
power source to normal operation mode and make a test weld.
The PFC circuits are not active in soft starting mode. To check that the PFC is working
properly, measure the intermediate voltage when the machine is in normal operating mode.
See: Power factor corrector on page 16.