Panasonic YD-500KR Operating Instructions Manual page 35

PERIODIC INSPECTION
Tips
Cautions for Dielectric Strength Test and Insulation Resistance Test Since this machine uses
many semiconductors, including thyristors, an imprudent dielectric strength test or insulation
resistance measurement could lead to a trouble of the equipment.
When you conduct these tests in compliance with your company regulations, he sure to observe
the following points.
Remove three cables coming from the switch box and connected to three input terminals. Tie
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the three input terminals altogether with a conductor to Short-circuit them.
Tie three input terminals of the magnet switch altogether with a conductor to short-circuit
2
them. Also, tie three input terminals of the magnet switch altogether with a conductor to
short-circuit them.
Remove two output cables connected to two output terminals. Tie the two output terminals
3
with a conductor to short-circuit them.
Using conductors, tie between the anode and cathode of the thyristors (SCR1-SCR6) to
4
short-circuit them. The conductors used in ①,② and ③ should have a sectional area of
2
about 1.25 mm .
Remove the case grounding terminal (wire number 9). The 500KR2 has the case grounded, using
5
a fasten terminal on the magnet mounting plate for the primary side, and another fasten
terminal on the rack frame(bottom plate) for the secondary side.)
Remove everything such as wire feeder, etc. and leave the welding power unit as a single
6
unit.
Remove all connectors from the printed circuit board.
7
Now that you have completed those preparations, you can proceed with the above-mentioned tests
without worrying about troubles or damages on the equipment.
Removal of the Top Plate and Side Plate.
①Remove of the top plate. (4 bolts)
②Remove the side plates.
(9 bolts each on the left and right)
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