Re: Transformers

Hi Steven,

After you have done the ohmic checks you have outlined, plug the HV side 
into the wall and measure the voltage on the LV side.  It is now operating 
as a step-down transformer with (approx) the same ratio of transformation.  
This actually checks to see if the transformer is still a transformer.

The only important test left is the hi-pot check which requires special 
equipment.  Basically, a hi-pot tester is a high-voltage DC low current 
power supply which one places between the HV bushings, HV bushing to case, 
etc. in every combination to check the HV integrity of the unit.  This is 
always done at the factory to new and rebuilt transformers.


>What is the best way to try to see if a transformer (pole or potential) 
>is good using only a DVOM?  Is it just a matter of making sure the 
>terminals aren't open circuited, and that the LV and HV sides aren't 
>shorted together (assuming they're really not electrically connected), 
>or is there more to it than that?