On 29 Oct 2005 12:36:31 -0700, wrote:

G'day,

Recently I've been given a defect welding inverter for parts.

While stripping it, I noticed the low-voltage rectifier (an inverter is
basically a switchmode PSU, a grizzly-computer PSU) that rectifies the
low-voltage AC to DC before exiting the machine. It consists of 3
diodes of 100A/600V each (RURU10060, for anyone interested).

The question: could I use this for rectifying the output of an
AC-welder (transformer type) to DC? Or should I use full-bridge
rectification for that (the 3 diodes in the inverter were wired as one
bigger diode; as normal in switchmode PSU's). Commercial rectifiers for
welders that I've seen all use full-wave rectification, which makes me
doubt if my 'grizzly-diode' would work satisfactorily.

Hope anyone with an electronics+welding background can help here...

Grtz,

Peter Dingemans,
The Netherlands.


Using a single diode will cause DC to pass through the welding transformer
secondary winding. This will cause the core to saturate. This will cause the
fuse to blow.

Mark Rand
RTFM