Polarity from Outlets question

In just picked up a Tributaries TX500 Power Manager to connection to my PPP. When I connect it says the Polarity is wrong as indicated by the light on front. Is it normal for the receptacles from the PPP to read this way? I did check with a polarity checker and it reads reversed. But the wall socket is normal.

The polarity checkers are not that smart and are easily fooled by a regenerator. That’s what’s happening. Please ignore.