Total posts : 45366
I am guessing that the 3-prong plug seen by rock95seven was a 220VAC type plug, and I did that when first installing my LPB carrier current system.
I plugged into an existing 220VAC circuit that had served a laundry dryer machine.
The result was poor, BUT when I wired directly into the AC panel the result was just as bad.
In fact, my system refused to work well going into the hots, feeding both legs of the 220.
I ended up with a neutral fed hookup, which has worked very well.
In the future I will try a different coupler into the 220V hots to try and learn why the first hookup worked so badly.
By “badly” I mean that the SWR (standing wave ratio) could not be reduced into the safe area.