Solar Generator grounding loop?

[adirondack_wanderer]

I have an EF Delta 2 Max wired up to solar and powering a few house circuits of 120v-only loads via a Reliance ProTran 2 transfer switch. This allows me to offset some of my electric consumption and reduce my electric bill. Is it ok to have the AC charge port plugged into grid power so if I run out of battery power the unit will use grid power until it charges again via solar? I watched a video about this on YouTube and I saw a commenter say that the AC plug ground prong being connected to the house ground would cause a "grounding loop" thus it should not be connected to the transfer switch when charging and it should not have the AC cable plugged in while feeding the transfer switch. I haven't had any problems so far but thought I'd ask to be sure.

I bought this system to take a plunge into the solar generation adventure because where I live we just get hammered with sun every day even during the winter and I wanted to Make something out of it. If I could go back and do things over I would have done a standalone inverter system like LithiumSolar demonstrates in one of his videos. But I've got this Bluetti unit with extra batteries and just trying to get some ROI on it but I wasn't aware of this ground loop business.

 

[OffGridForGood]

I have an EF Delta 2 Max wired up to solar and powering a few house circuits of 120v-only loads via a Reliance ProTran 2 transfer switch.

The Reliance doesn't transfer N or G ie common Neutral

This allows me to offset some of my electric consumption and reduce my electric bill. Is it ok to have the AC charge port plugged into grid power so if I run out of battery power the unit will use grid power until it charges again via solar? I watched a video about this on YouTube and I saw a commenter say that the AC plug ground prong being connected to the house ground would cause a "grounding loop"

This will depend on how the EFDelta is connecting to the CLP and the house panel:
Does your EF Delta actually have a ground? where does it connect to the house ground? - ie did you tie ground conductors together at the CLP or leave them isolated from one another?
What about the Neutrals?, since your EFD is creating a N, that is only connected to the house neutral via the charging plug, at the CLP there is no switching of N, so I assume these are isolated from each other - unless you connected the generator plug N to the house N in the CLP.
Sounds like a good question for @timselectric

 

[adirondack_wanderer]

The Reliance doesn't transfer N or G ie common Neutral

This will depend on how the EFDelta is connecting to the CLP and the house panel:
Does your EF Delta actually have a ground? where does it connect to the house ground? - ie did you tie ground conductors together at the CLP or leave them isolated from one another?
What about the Neutrals?, since your EFD is creating a N, that is only connected to the house neutral via the charging plug, at the CLP there is no switching of N, so I assume these are isolated from each other - unless you connected the generator plug N to the house N in the CLP.
Sounds like a good question for @timselectric

At the 9:00 mark he shows connecting the ground and neutral which is how I did mine. I apologize for my misunderstanding of your statement that it doesn't transfer the neutral or ground but from what I can see the neutral on the transfer switch is connected to the neutral on my main service panel and the same for the ground (I do not have a sub panel set up like in the video). You'll also see the comment by neocrypto9368.

My unit does have a three-prong plug for AC charging so would certainly appears to have a ground but I noticed something odd. Before I went this route I had the unit in my office with all of my office electronics plugged into it and I always had it plugged into grid power. I had solar running through the exterior wall and if it ever discharged below 30% it would automatically kick on the grid power and basically pass through power to anything plugged in. It was basically serving as a UPS. I just happened to have another cyberpower UPS and I had it plugged into the EF unit sort of like an extension cord and the cyberpower UPS has a light on it indicating ground fault, and that light has always been on. If I plug the cyberpower UPS into the wall the light turns off. If I explained that well then does that indicate that EF unit does not have a true ground connection?

What is a CLP please so I can respond to the rest of your questions?