I just finished helping a buddy track down a "failed" GFI wall socket (receptacle) in his camper van.
The GFI always showed a red LED. (Although when we manually tripped it, and then turned on his water heater before resetting, it would show green. (There's a clue here.))
He has a Mutliplus 12/3000.
I had enabled AES in his Multiplus to save power in standby. (20 W)
When powering up his wall plugs initially, his GFI showed a red LED. It would not trip on Test. That is, it gave the appearances of not working - being "compromised" as the Internet experts say.
So we replaced it with another.
To make a long story short, I found that the GFI needs to be powered up initially with the Multiplus NOT in AES mode.
It appears that the AES modified sine way, or perhaps not being having a high enough r.m.s. voltage, is incompatible with GFI wall plugs for service in the US. (Or at least, not compatible with the Levitron brand.)
And so we have made it a procedure in his camper van to switch on his Water Heater before he energizes his wall plugs for the first time.
Once the GFI shows green after initialization, it will trip properly, even when the Mulitplus is in AES mode. But the GFI will not Reset unless the Multiplus is in pure sine wave mode.
