ballast problems....?

I have a 400w mh/hps ballast and I have it plugged in an extension cord with out the ground so I bought a converter and when i went to plug it back in it sparked and my mh light won't come back on... and there's power to the extension cord any ideas wat happened?

Got a pic of the ballast? I'm gonna assume it's a magnetic. Is it in a housing?

Yes its magnetic and yes its in a building

did you unplug it, add the converter & plug it back in?? a ballast needs 15 min or more to cool b4 relighting.
or try it again w/out the converter

Yes I did and before it went out it was hot and kind of a burning smell