Finding a Ground in an Inverter

Discussion in 'General Electronics Chat' started by stevenkt, Feb 27, 2009.

  1. stevenkt

    Thread Starter New Member

    Feb 27, 2009
    My plant has a commercial inverter that takes 3 phase 480V AC and rectifies it to DC. A battery also provides DC as a backup. DC is then inverted to 120V AC through an inverter then a Constant Voltage Transformer (CVT).

    Here is my problem, I have a DC ground detected on the DC portion of the inverter. When I change out the CVT (which of course is on the AC portion of the inverter) the ground goes away. Does that make sense?

    If the CVT has a ground in it it would be an AC ground. Would I expect the DC ground detector to pick that up? If so, whats the theory behind this. Seems that an AC ground in the CVT would simply draw more DC not show up as a ground.