grounding

[ant17]

hi guys i have a backlight inverter with ac output of about 1500vac. Which i convert for my pmt scintillation project to dc through a bridge recitifre .  I have no problems with it but being battery powered the inputs and grounds are floating at high voltage  so you can get a zap from it from the ground terminals. I don't think its a good idea having hf ac floating around circuit is there anyway to correct this with out fixed ground as i would like keep it hand held in a metal case