On Mon, 11 Apr 2011 13:25:02 +1000, "Phil Allison"
wrote:



"Phil Allison"


High voltage spikes on the primary could also cause insulation failure
leading to the damage seen in the pics - lightning does this sort of
thing.
So also could back emfs from the blower fan if the is a bad connection in
the AC supply feed.

I suggest you provide the next replacement for that vulnerable tranny with
some "protection" - firstly an in-line fuse of say 1/4 amp AND a
capacitor wired across the primary of say 1uF rated for continuous use
across the AC supply.

If there is an overload on the tranny, the fuse will blow.

The 1uF capacitor should suppress spike voltages enough to save the tranny
from harm.



A capacitor across an AC supply??????????????? As a surge
protector????
Have not heard of that before.


** Then your ignorance is showing.

The stated reason for the capacitor was in relation to the "blower fan"
inside the same unit as the small tranny.

The event the cap has to deal with is a back emf surge generated by that
fan when the AC supply is suddenly disconnected - for whatever reason.


A capacitor across the AC line would appear as a load

** Draws 45mA continuously.

Yawnnnnnnn....

- and could form a resonant l/ci tank circuit,

** Yawnnnnnn....

(snip absurd drivel)


There are 2 other POSSIBLE issues here though - - -.

Both are perhaps long shots - but mabee worth investigating.

The transformer primary APPEARS to be saturating.


** The primary appears to be EXPLODING !!

You ridiculous ******.


.... Phil

Phil - your mamma should wash your mouth out with soap.
I SAID the other two scenarios were long shots - but so is everything
else that has been suggested. The windings of the trasnformer do not
APPEAR to be overheated - looks like just blackened at the connections
between the winding and the connecting wires.

It is definitely a strange failure - and I don't think it has been
properly analyzed to determine exactly what/where the problem is.
As Arthur Conan Doyle said, "after you have eliminated all the
possibilities, whatever remains, however improbable, must be the
truth"