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reid-dyer asked

Negative grounding with gfci solar array breaker

Hey everyone I asked a similar question a few days ago and the only answer I got was to read wiring unlimited. I have several times, it's not answered that I can find. How do I wire my solar array ground fault breaker in.

80A 150VDC, Two Pole
PNL-GFDI-80D (Formerly OBDC GFP/2)

Says outback but made by carling

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Ive read these following instructions from equipment manuals.

Only 1 point of grounding, so is that only one wire going to earth ground via a ground rod?

Ground the array frames to earth ground but not the array negative. The negatives on my charge controllers are not isolated it states. Understood.

Connect all equipment chassis to the negative bus bar. Bonding the chassis back to negative bar makes sense so if there is a short from positive to the frame of any device there's no shock hazard and the breaker feeding the device should trip from the short. I've read that connecting the earth ground provides additional safety and also allows a fault for possible ac voltage backflow from inverters should that condition arise. Ok. Fine.

The ground fault breaker severs my positive wire via the built in .5 amp breaker should my array wiring or charge controllers have a fault from positive to ground. This is accomplished by hooking the white wire to my negative side and my green wire to ground, which is earth grounded.

NOW....GROUND THE NEGATIVE SYSTEM BUSBAR TO EARTH GROUND ???????

First, if my negative busbar is earth grounded and my charge controller negatives are not isolated then I just earth grounded the solar array negatives...right?

2nd I actually just bench tested the ground fault breaker with a smaller 4 wheeler battery. As I expected if I hook the white wire to a battery pole and green to the other pole the breaker trips as it should. By the way it worked both ways regardless of which one goes on positive and negative to my surprise. This simulates my white on negative and a positive short to my ground wire. But if white and green are both connected to earth ground as they would be if my system negative bus bar was earth grounded, I can short the battery positive to the ground/white and throw sparks and almost melt the wire but IT WILL NOT TRIP ! because there is no differential between the negative and the ground ! I read a post here that started a few years back called "chassis grounding clarification" started by mbonner. Replies were made by gazza, rjoustra, Kevin windem and Mark Anderson regarding the same issue but on a van. This is a house I'm on. There were replies as late as November 2023. I can not fathom how my breaker will work in this configuration unless either my array frames are not earth grounded but rather go only to my ground fault breaker alone which leaves my areay rack ungrounded OR I do not earth ground my negative buss bar. I know this a lot but it seems that many/most on the web don't understand or do not have a good answer. Can somone please send a diagram or explain this to me. Thank u.

Grounding
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