Input Bridge (0558007068 / 0558007077)) - ESAB Powercut 1600 Service Manual

SECTION 4 DESCRIPTION Of OPERATION
4.3

Input Bridge (0558007068 / 0558007077))

The input bridge is a 3 phase, full wave rectifier, which converts the AC input voltage to DC. The device is
designed to deliver a maximum current of 160 Amps of forward current.
Primary AC power enters the rectifier where it is rectified by the six diodes inside BR1. The rectified output
is coupled to the buss supply capacitors and the L1 input inductor.
A "precharge" Inrush circuit is mounted to the output of L1 and is in parallel with the Main Contactor. This
circuit allows the Buss supply to charge gradually during initial power up. When the operator closes the
torch trigger, the Main Contactor is used to supply full current output to the buss supply.
4.3
Testing: 760K Ohm forward resistance, reverse resistance - high resistance (1.5 Meg-Ohm or greater) out
of circuit. In circuit resistance is 99 K Ohm.
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