"Venus²" wrote in message
...

"vMike" wrote in message
. ..
I have a 120v to 24vac transformer for a lawn sprinkler system that has
failed about 3 times since I purchased the house. This time I took the
windings apart and found the break in the 120v winding. I live in a
lightening prone area. Is this failure most likely from power surges or
is
there some other possible cause.

Thanks.

Mike




I do not think the lightning is the cause, I think it was caused by the
overheating of the transformer itself, this happened because the
transformer is rate too low for your load. Check the voltage before
applying the load, and then apply the load to see its voltage drop. If
the drop 40% or more then, you'll need to buy a bigger transformer, do not
buy the exact model.



Cam

The transformer was an original factory replacement part. Do I check the
voltage drop on the load side or the line side? The control box is outside
and in sun in the morning when the sprinklers are on, could the sun cause
the overheating.
Mike