At 02:38 PM 5/18/2005, Jinx wrote:
> > Subject: Questions concerning Block Transformer VB 0,35/2/6
> >
> > Firstly you are quite correct in your diagnosis that the transformer =
is
> > very close to saturation. This is more apparent under no load conditi=
ons
> > than under full load, and is mainly due to the very small percentage =
of
> > iron core present in these small transformers.
> >
> > The temperature rise under no load condition can certainly be higher
> > than in a heated condition under full load.
> >
> > At 70=B0C ambient and 100% load and temperature stability the tempera=
ture
> > rise should be expected to be approx. 40K.
> >
> > The DC resistance of the primary winding should be approx. 14870 Ohm.
> > This very high resistance is needed to obtain the inherently short ci=
rcuit
> > proof characteristics, of the transformer."

<catching up on old email>

Jinx - based upon the above, I'd consider dealing with the transformer in=
=20
current mode rather than voltage mode.  In other words, add a sufficientl=
y=20
low value resistor to the output so that it is in fact running at full=20
load.  Maybe even try running it into an almost short circuit.

Does it in fact run cooler loaded than unloaded?

dwayne

--=20
Dwayne Reid   <dwayner@planet.eon.net>
Trinity Electronics Systems Ltd    Edmonton, AB, CANADA
(780) 489-3199 voice          (780) 487-6397 fax

Celebrating 21 years of Engineering Innovation (1984 - 2005)
  .-.   .-.   .-.   .-.   .-.   .-.   .-.   .-.   .-.   .-
     `-'   `-'   `-'   `-'   `-'   `-'   `-'   `-'   `-'
Do NOT send unsolicited commercial email to this email address.
This message neither grants consent to receive unsolicited
commercial email nor is intended to solicit commercial email.


--=20
http://www.piclist.com PIC/SX FAQ & list archive
View/change your membership options at
http://mailman.mit.edu/mailman/listinfo/piclist