timselectric
If I can do it, you can do it.
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I really thought that they did, from all of the discussions about removing the ground screw.
But, maybe they have changed their design.
I guess that time will tell.
MPP Solar LV1012 N-G Bond
- Thread starter thetimbo
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But, maybe they have changed their design.
I guess that time will tell.
12VoltInstalls
life passes by too quickly to not live in freedom
That’s an entirely different model and config than the 1012LV-MK
timselectric
If I can do it, you can do it.
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True
That's another issue.
There's no standard between products.
Even if from the same company.
Zwy
Solar Wizard
Could be the powerstrip has a fault. Notice I said no wires connected to output.
Having variables when testing leads to erroneous conclusions.
If it has an input G and that G is connected to a grounding busbar in the main panel, then it is earthed if the main panel is connected to a ground rod.For this unit there is no grounding screw or lug provided for connecting to a grounding rod (manual also does not state anything about grounding). In addition, my receptacle tester lights show "correct wiring". (no open ground, etc.) ?
If you have a clamp ammeter, it is best to check for current on G when a load is placed on the system. If you have any current on G, you have a problem.
I'd remove the power strip, wire in a 120V receptacle and then test with a good sized load.
12VoltInstalls
life passes by too quickly to not live in freedom
The reason I didn’t explore further was time. I had zero amps on the incoming 120VAC Green with an 800W load.
However, the subpanel or main I’m connected to has a poor connection somewhere as I had 84ohms across G and N which gave me low confidence in the proving.
For OP the Green/bare test is what he needs
Last edited:
Zwy
Solar Wizard
timselectric
If I can do it, you can do it.
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If the power strip is giving results of a connection, with some resistance. You would only see this in an un bonded situation. Because in a bonded situation, the reading is a connection with zero resistance. When both connections exist, at the same time. The zero resistance is stronger reading.
I asked Ian about how to bond the neutrals. IE: Should I just wire nut the input and output together and bypass the terminals. Well Ian got back to me and said, No, I have to run the neutral from the main panel to the sub panel ... Picture. (honestly, I'm not sure what the difference is?)
But, obviously, I have a power strip and not a subpanel. And I don't think I want to be pulling any lines out of my main panel. So since MPP Support told me the unit bonds N/G on battery and have since discovered that it does not, I've asked to return the unit. I can not use this with a floating ground... I'll probably look to replace it with either a Victron or Samlex EVO (yes, I know I'll have to add a SCC then too)
But, obviously, I have a power strip and not a subpanel. And I don't think I want to be pulling any lines out of my main panel. So since MPP Support told me the unit bonds N/G on battery and have since discovered that it does not, I've asked to return the unit. I can not use this with a floating ground... I'll probably look to replace it with either a Victron or Samlex EVO (yes, I know I'll have to add a SCC then too)
timselectric
If I can do it, you can do it.
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Neutral from main panel to inverter.
Neutral from inverter to loads panel (or power strip, in your case)
Both neutrals land on the Neutral terminal, in the inverter. (If there's only one Neutral terminal)
Or a wire nut, or a jumper. (Whatever connects all neutrals together)
Neutral from inverter to loads panel (or power strip, in your case)
Both neutrals land on the Neutral terminal, in the inverter. (If there's only one Neutral terminal)
Or a wire nut, or a jumper. (Whatever connects all neutrals together)
Well, there are two neutral terminals (1 for input & 1 for output). I'm not sure if they're big enough to jam a jumper in there. Do the neutrals actually have to connect to the terminals? If so, I guess I could run a pigtail out of them.
timselectric
If I can do it, you can do it.
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12VoltInstalls
life passes by too quickly to not live in freedom
My unit is barely a month in service and appears to be bonding N-G on battery. Purchased through watts247.
Before you return- disconnect incoming/outgoing power. See what N-Gs are on battery only. Mine was closed grid-Green to Inverter-Green, and inverter N-G are closed. No grid connection like I said.
Try it
timselectric
If I can do it, you can do it.
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Yes
It must be on battery/ inverter only.
No grid passing through.
It must be on battery/ inverter only.
No grid passing through.
Diysolar123
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I have the lv2424 and it definitely does NOT bond N/G on battery....even tho they said it does; probably varies by model and they have only a single answer they give out ;-)
when it comes to bonding you have to deal with a variety of situations:
1)plugged in, on grid: LNG are all present and wired thru
2)plugged in, on battery(when grid line power drops) NG are still present and wired thru, L is coming from AIO not grid; you may still be getting bonding via input and output N's getting tied together...and the N/G bond in the panel gives you your bonding like always.."maybe"...
3)UNplugged, on battery; incoming LN are lost, you still have G(if you wired in a separate ground) but its floating from N
in the case of 1&2 you could still have N/G bonding in your panel if the AIO is bonding neutrals only together...
for case 3, if you have lost your neutral pathways and the AIO is ONLY providing N-to-N bonding on battery you will have lost your ground bond.
sady there is no "clean" way to solve this other than adding in your own controlled transfer switch with correct bonding based on your specific AOI wiring... if you have lost the grid input entirely(unplugged) you really need to test your system to see what it is doing. I had an older transformer based inverter that not only switched all 3 wires but had a jumper you could install that would cause another relay to bond G/N on battery. It weighed a LOT and cost a lot hehe...
next is a terrible idea ;-)
a "not recommended but I did it anyway" is to bond the ground and output neutral...this WILL result in "double" bonding (BAD) in your wiring when you are plugged into the house/grid, but does mean you can yank the plug right out of the wall and everything will have a "proper" N/G bonded ground path. If you end up with even slight ground currents this will pop GFI circuits so fair warning.
sure wish there was some type of "standard" for the inverter market but there is not and asking the company rarely gets you an answer from someone that "really" knows what is going on.
12VoltInstalls
life passes by too quickly to not live in freedom
I get frustrated when I think about this.
On batteries no grid the 1012LV makes itself bonded.
One would assume that when grid is present that N-G would be opened and the feeder stanchion or outlet or whatever would supply the N-G bond. When I get around to checking this I HOPE that’s what I find!
It’s nothing but relays; if I can understand it, the folks that design these things should already understand and have it operate properly.
Zwy
Solar Wizard
From everything I've ever read on MPP and Growatt inverters, the inverter has N-G bond under battery power.
It's when you have many say it is or isn't that creates confusion.
Then you get threads like this where the distributor sells a different product with the same model number. https://diysolarforum.com/threads/growatt-and-mpp-gave-different-answers.36906/
12VoltInstalls
life passes by too quickly to not live in freedom
as my 1012LV-MK does
Yes.
I’ll get around to testing eventually.
First step before I can test is looking at the outlet and subpanel. My incoming grid N-G reads 86 ohms or something - that was unexpected. 12ga cord for a few hundred feet is basically zero ohms end to end so that ain’t it.
The little 60A subpanel in the barn may not actually be a subpanel (farmer self-installed 50 years ago probably) and if it is direct from the pole I do know there’s no ground rod at the subpanel. I’ll need to look inside to see how it’s wired; there’s a dbl breaker acting as a main and no idea about ground.
The 86 ohms bothers my head.
