The transformer lent to me by the housing warehouse will only work with two-prong plugs.  If I plug in a grounded cord of any kind it trips the transformer and I have to reset it.  Every time I reset it, it does this.  Housing gave me two transformers and both of them do this.  It's not the fuses because I can plug in an ungrounded plug and it works just fine when I reset it.  Has anyone else had this problem?

Where do you live?  Inside or outside the base?  If out side it sounds like you may have an improperly installed ground in your residence.

As dumb as it may sound, try reversing (i.e. 180) the plug into the wall outlet. Heard of others having this same issue, and solved it that way.