EG4 6000EX - Double Ground/Neutral

[HLD]

I have an off-grid 6000ex (no grid in/out) that has the AC out connected to a main panel/load center. The panel has a ground/neutral bonding screw like the one shown in this image:

In attempting to learn more about ground neutral bonding I discovered that the LVX-6048 does ground/neutral bonding when in battery mode ( so for me all the time ) and assumed this model would be similar. (Signature Solar hasn't responded to my email yet)

If the two models do handle g/n bonding the same:
Do I have a double ground neutral bond? If so, what type of problems would that present in my system?

 

[Quattrohead]

They say you can have ground loops but I am not so convinced. If the run from the inverter to panel is short I would not worry about it.
But a single ground rod or 2 placed no more than 6/10 feet apart and firmly connected together is very important.

 

[HLD]

They say you can have ground loops but I am not so convinced. If the run from the inverter to panel is short I would not worry about it.
But a single ground rod or 2 placed no more than 6/10 feet apart and firmly connected together is very important.

The run from the inverter to the panel is 5' 2" of 6-3. Is the length important because a longer one presents more opportunities for current to leave that loop? Just like grounding, the ground neutral thing gives me 10 questions for every 1 I think I answer.

 

[Dona40]

The way I understand grounds is that if your Solar setup is a stand alone and there are no utility lines, then the first panel would be treated the same as the wiring in a house with utilities. Any sub panels would have the non-bonded grounds. Grounds are only to prevent user shock from a short. Nothing more. Also, there should be no current flow on that ground wire if everything is proper. A ground wire is basically a path back to the neutral through the dirt at the utility pole. I'm not ever really sure if there would be a need for an Earth ground if it's stand alone. Some gas generators have what they refer to as a floating ground for this reason. Correct me if I'm wrong, but that how I understand it.

 

[PreppenWolf]

You need the N-G bonded and a ground rod connected even if this is off grid with no grid service. There are outlets and devices requiring ground, as well as lightning and shorting concerns.

If your system doesn't have a EGC (earth ground conducter) then any short can energize the object that failed and what it is touching. Earthing allows voltage a path to flow so when you go hunting for that issue you don't die when you touch it.

 

[HLD]

You need the N-G bonded and a ground rod connected even if this is off grid with no grid service. There are outlets and devices requiring ground, as well as lightning and shorting concerns.

If your system doesn't have a EGC (earth ground conducter) then any short can energize the object that failed and what it is touching. Earthing allows voltage a path to flow so when you go hunting for that issue you don't die when you touch it.

I have an EGC, and I definitely have a N-G bond. What i'm concerned about is that the N-G is being bonded in two places and what symptoms that might present for me to determine if this is the case.

 

[PreppenWolf]

You're not going to notice anything unless you go looking. The lights will still turn on. Your fridge will still stay cold. The loop avoidance is because of safety concerns when working on the system (i.e. you must disconnect more than one line to isolate it fully) and the potential to create an antenna generating signal noise.

 

[HLD]

You're not going to notice anything unless you go looking. The lights will still turn on. Your fridge will still stay cold. The loop avoidance is because of safety concerns when working on the system (i.e. you must disconnect more than one line to isolate it fully) and the potential to create an antenna generating signal noise.

Hm. I'm very curious about this signal noise. Is this audible? Our system performs normally with a single oddity. When running a very specific load - a hair dryer on medium (not low or high), the inverter, which has a transformer (6000ex), gets very loud. It sounds like it is resonating. No other loads we've run happen to do this. Could that be a symptom of a double N-G bond/loop?

 

[PreppenWolf]

Hm. I'm very curious about this signal noise. Is this audible? Our system performs normally with a single oddity. When running a very specific load - a hair dryer on medium (not low or high), the inverter, which has a transformer (6000ex), gets very loud. It sounds like it is resonating. No other loads we've run happen to do this. Could that be a symptom of a double N-G bond/loop?

By noise we mean electromagnetic as in radio waves, etc, not audible. The 6500's cooling fans are pretty loud. This is normal as they are high static pressure.

 

[HLD]

By noise we mean electromagnetic as in radio waves, etc, not audible. The 6500's cooling fans are pretty loud. This is normal as they are high static pressure.

I've got the fans humming pretty loud. The thing sounds like a jet engine when 5kw solar input is reached as well. But this other sound from the very particular load is something else. Deep and resonant, not sure if it's normal as i've never had an inverter with a big ol transformer in it before.

 

[EZ Generator Switch]

I have an off-grid 6000ex (no grid in/out) that has the AC out connected to a main panel/load center. The panel has a ground/neutral bonding screw like the one shown in this image:
View attachment 121300
In attempting to learn more about ground neutral bonding I discovered that the LVX-6048 does ground/neutral bonding when in battery mode ( so for me all the time ) and assumed this model would be similar. (Signature Solar hasn't responded to my email yet)

If the two models do handle g/n bonding the same:
Do I have a double ground neutral bond? If so, what type of problems would that present in my system?

Yes that green screw needs to be removed because you are feeding it from the main panel in the house. This is a Sub -Panel, the ONLY place a neutral gets bonded is at the main disconnect. This is the reason any BONDED generator of any type must switch the neutral. The issue we run into is SOME Floating neutral systems ( could be generator , inverters etc..) those particular manufactures do NOT want their "neutral" to be bonded. Eco Flow I know will let you bond their neutral to meet the NEC, Ego-nexus will let you bond. I only know that going thru rigorous correspondence with the manufacture and helping customers.
Wait , it gets worse! lets say you have a Bluetti ( not picking on them just know this) and you own a Lennox or Boderus furnace. These systems will not run...here's why> the neutral is floating (no bond with the house neutral) and those systems are "looking" for that neutral/ground bond at the first means of disconnect (your main service) . Many peeps automatically blame the transfer switch...no "news flash" The systems you just spent big bucks on will NOT run your equipment. In the future more and more equipment will require the neutral to be bonded. FYI >>> neutral bonding plugs are illegal because they bond the neutral out in the circuit somewhere not at the main panel. A NEC violation and a nightmare for safety.

 

[HLD]

Yes that green screw needs to be removed because you are feeding it from the main panel in the house. This is a Sub -Panel, the ONLY place a neutral gets bonded is at the main disconnect. This is the reason any BONDED generator of any type must switch the neutral. The issue we run into is SOME Floating neutral systems ( could be generator , inverters etc..) those particular manufactures do NOT want their "neutral" to be bonded. Eco Flow I know will let you bond their neutral to meet the NEC, Ego-nexus will let you bond. I only know that going thru rigorous correspondence with the manufacture and helping customers.
Wait , it gets worse! lets say you have a Bluetti ( not picking on them just know this) and you own a Lennox or Boderus furnace. These systems will not run...here's why> the neutral is floating (no bond with the house neutral) and those systems are "looking" for that neutral/ground bond at the first means of disconnect (your main service) . Many peeps automatically blame the transfer switch...no "news flash" The systems you just spent big bucks on will NOT run your equipment. In the future more and more equipment will require the neutral to be bonded. FYI >>> neutral bonding plugs are illegal because they bond the neutral out in the circuit somewhere not at the main panel. A NEC violation and a nightmare for safety.

I don't have a sub panel. The one pictured here is my main panel. It goes inverter > panel > outlets. Does that still apply? Part of my confusion stems from the fact that these little panels are sometimes used as sub panels in my area as well.

 

[EZ Generator Switch]

I don't have a sub panel. The one pictured here is my main panel. It goes inverter > panel > outlets. Does that still apply? Part of my confusion stems from the fact that these little panels are sometimes used as sub panels in my area as well.

If that is your only panel then that ground screw remains bonding the neutral /ground buss to the can. Your issue is will the inverter company let you connect their neutral to that bus bar BECAUSE from that buss bar should be a equipment grounding conductor to two ground rods (6' apart minimum). You will grounding their neutral at this point, will they let you do that? From NEC article 230 services and article 250 grounding

 

[HLD]

If that is your only panel then that ground screw remains bonding the neutral /ground buss to the can. Your issue is will the inverter company let you connect their neutral to that bus bar BECAUSE from that buss bar should be a equipment grounding conductor to two ground rods (6' apart minimum). You will grounding their neutral at this point, will they let you do that? From NEC article 230 services and article 250 grounding

I'm not sure if EG4 will "let me" do it. Or if it's correct. But I am. My neutral and ground wires are all on the same bus bars which are connected to a single GEC 8' in the ground. What i'm really uncertain about is how the inverter internally handles ground/neutral bonding when inverting from battery power; And if having two points (inside the inverter and in the main panel ) where the neutral and ground are bonded will cause problems, and if so, what those problems are.

It's my understanding that some inverters will bond N/G when inverting from battery and not when from AC input. I don't have AC input so I want to make sure N/G is bonded correctly and not too often. ( if that's a thing )

I've been unable to find any information on what happens if you bond N/G twice, some sources say it will cause some kind of feedback loop, some say nothing will work at all, other say it will work until you get shocked dead. It appears to be as mythical as the subject of grounding itself.

I'm sure a lot of this stems from my lack of understanding regarding why the inverter would bond neutral and ground when inverting from battery in the first place. When I look at a diagram of a 240v circuit it appears the role of the neutral, in my implementation, would be to carry the difference between the 2 hot wires, and provide a path for it to ground. Not sure why a second bond makes that a problem?

 

[ig1628]

Hello yall, I found this video a while back and the way he explains grounding/neutral is very elementary. Hope this helps.

 

[EZ Generator Switch]

I'm not sure if EG4 will "let me" do it. Or if it's correct. But I am. My neutral and ground wires are all on the same bus bars which are connected to a single GEC 8' in the ground. What i'm really uncertain about is how the inverter internally handles ground/neutral bonding when inverting from battery power; And if having two points (inside the inverter and in the main panel ) where the neutral and ground are bonded will cause problems, and if so, what those problems are.

It's my understanding that some inverters will bond N/G when inverting from battery and not when from AC input. I don't have AC input so I want to make sure N/G is bonded correctly and not too often. ( if that's a thing )

I've been unable to find any information on what happens if you bond N/G twice, some sources say it will cause some kind of feedback loop, some say nothing will work at all, other say it will work until you get shocked dead. It appears to be as mythical as the subject of grounding itself.

I'm sure a lot of this stems from my lack of understanding regarding why the inverter would bond neutral and ground when inverting from battery in the first place. When I look at a diagram of a 240v circuit it appears the role of the neutral, in my implementation, would be to carry the difference between the 2 hot wires, and provide a path for it to ground. Not sure why a second bond makes that a problem?

All comes back to the inverter company...just call them they should have a answer 4u

 

[ig1628]

Has anyone looked into the EG4 6000EX inverters as to neutral-ground bonding? I have 2 in parallel (I have a email to SS to find out if these units are bonded as well)totally off grid and have generator as back up. Just wondering what are my options, I just installed these units 2 weeks ago replacing Growatt SPF5000ES. Had to get rid of that auto-transformer set up.

Not totally finished with install waiting on more parts.

Thanks

 

[FilterGuy]

EGC (earth ground conducter)

I have always used the term EGC as Equipment Grounding Conductor.

 

[FilterGuy]

Has anyone looked into the EG4 6000EX inverters as to neutral-ground bonding? I have 2 in parallel (I have a email to SS to find out if these units are bonded as well)totally off grid and have generator as back up. Just wondering what are my options, I just installed these units 2 weeks ago replacing Growatt SPF5000ES. Had to get rid of that auto-transformer set up.

Not totally finished with install waiting on more parts.

Thanks

We have discussed the EG4 6000EX in other threads, but I don't yet have a definitive answer on how it works.

* It seems to be a low frequency inverter. (If nothing more, the weight tells us it has the LF big-honking transformer in it)
* It clearly switches the two hots.

* It is NOT clear what it does with neutral.

Based on the discussions in other threads, my best guess is that the model of the inverter would look like this.



Notice that with this arrangement, the neutral is generated by the output transformer in both the inverter mode and pass-through mode.

@ig1628 : Could you do a couple of tests to help us sort this out?

1) With the inverter completely disconnected from everything (No PV, No Battery, & No AC-in), measure continuity/resistance from neutral-out to Ground-Out. If the above model is correct, there should be no continuity.

2) With the inverter completely disconnected from everything (No PV, No Battery, & No AC-in), measure continuity/resistance from neutral-out to Neutral-in. If the above model is correct, there should be no continuity.

3) With the inverter hooked up to AC-In, in Pass-through mode, and no load on the output, measure the voltage from neutral-out to ground-out. If the voltage is zero it does not tell us much, but if the voltage is more than 1 or two volts, it supports the above model.

4) If you are willing to open the unit, a picture of the output transformer would be nice to see. (Warning: Opening the unit may void the warranty so I fully understand if you do not want to do this)

 

[ig1628]

Hello filterguy, thank you for yhe response, ok all potential off I have Meg ohms on output groud to neutral, Meg ohms input to output neutral and approx 24 volt neutral to ground with inverters on output line breaker off and generator input line on. I did get a reply from SS and this is what he said. "
To answer your question about Ground neutral bonding, the units are bonded internally. The GNB location is determined by whether you have a grid or off-grid application and should be wired by your installer, as each configuration the bond will occur in a different spot before or after the inverter."

Hope the info can shed some light on the questions.