section 6
6.4.3 power shunt installation
caution
There are two cables that attach to the shunt pick-up points:
a two conductor cable drives the ammeter
a three conductor which provides the current feedback signal to PCB1 (control PCB).
Dressing of the 2 conductor cable is not critical.
The following is the dressing procedure for the 3 conductor cable.
•
The breakout point should be physically at the middle of the shunt. The breakout point is the place
where the conductors exit from the outer insulation jacket.
•
The black and clear insulated wires must be kept next to the shunt and under the cable ties.
•
The wire terminals for the black and clear insulated wires should be oriented in parallel with bus bars
as shown.
three leads
instability or oscillation in cutting current can be caused by im-
proper dressing of shunt pick-up leads.
poor torch consumable life will be the result.
Terminals parallel
to bus bars
clear insulation
two leads
•
It is important to have the barrels of the black
and clear insulated wires, from the three lead
cable, be pointing in opposite directions.
•
The third wire attaches to the bus bar on the left
with the shunt mounting hardware. Orientation
of this wire is not critical.
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