Re: Todd repair questions (it works now)

["Joe Smalley" <joes@worldfront.com>]

The extra winding supplies 15 volts to the PWM chip once it starts running.
It has nothing to do with the diode current. There is no PWM chip on the
slave board so there is no need for the winding on the slave transformer.

Joe Smalley
Rural Kitsap County WA
Fiesta 48 volts
NEDRA 48 volt street conversion record holder
joes@worldfront.com
----- Original Message -----
From: "Paul G" <neong@gte.net>
To: <ev@listproc.sjsu.edu>
Sent: Saturday, March 30, 2002 5:49 PM
Subject: Re: Todd repair questions (it works now)


> Hi,
>
> I wanted to thank the list for the help. The repair would have been done
> much sooner except for a Newark messup. On the positive side they credited
> me for the order they shipped to the wrong adderess then sent me the parts
> again as promos (free).
>
> I replaced the MUR460's on both boards with new diodes of the same type.
It
> was listed and available from Newark for 60 cents each in single unit
> quanities (I found another place later that listed them for 36 cents
each).
>
> It seems that there is a reason that the slave board went but not the
> master board. The master board has another winding on the transformer that
> looks like it would remove some of the load from that diode. If I'm
> guessing right, that is the voltage feedback (?). Well, I had pulled the
> board out already and figured I would install the new diode with a longer
> lead lenth like the other side (the main cooling for the diode is out the
> leads). The master board diode didn't have darkened lead in wires. Is that
> extra winding the reason that diode survived?
>
> Neon
>