Subject: converting ac welder

From: [email-masked]
Date: Sun, 28 May 95 01:09:15 EST

-=> Quoting Internet: [email-masked] to ** All ** <=-

 IJ> conservative. One way to parallel diodes is to insert a
 IJ> small resistance in series with each one.  The better
 IJ> matched the diodes are, the smaller the resistance can be.
 IJ> The purpose is to "swamp" out the

Almost any resistance will have a seriously detrimental effect on
the welder. Power diodes are not precision devices, there will be
variances.

 IJ> By dropping a .5 ohm resistance in series with each, the
 IJ> load is balanced more closely.

Ohms Law E=IxR consider 100amps and .5ohms
  100x.5= 50volts drop across the resistor!

Also consider Power=IxIxR
  100x100x.5=5KW power consumption in the resistor!

Series parasitic resistance is not the answer, not at welding
currents and voltges. 

 IJ> Probably best if you can find single diodes big enough,
 IJ> instead!

That is the only right answer!

Regards,
Brad Chaucer

... "I grabbed it once, but I didn't shake it" - Bill Clinton
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