EG4 6000XP and Grid "Input" neutral

[Tripplett]

I was watching @Will Prowse latest video again on the 6000XP showing two units in parallel. In it at 6:06 he talks about the grid connections. He used a NEMA 6-50P plug to supply the Grid Input for the XP's pass through and battery charging. That plug doesn't carry a neutral wire. That makes sense because the 6000XP can't use a 120v feed for the grid in connection, it must be a 220v connection. Several of us have tested this.

So, given that, it seems like you could create a bond in the off grid panel or in the 6000XP AND have a Grid Input connection safely, without any unwanted neutral loops. No one is discussing this way of wiring the 6000XP.
The manual does say to "use a multimeter to confirm your AC Input lines (L1, L2, and neutral)" (screen shot below) so that implies it expects a neutral however I don't know why. I want to create the N-G bond at the off grid panel or at the inverter AND also have a 220v grid input for pass through/charging.
I'd love to hear other's thoughts on this.

Will also states @ 8:03 wrongly in the video that the 6000XP can dynamically switch the N-G bond based on if it is in pass through mode or not. That isn't the case based on everyone's testing that I've seen so far. And it even says in the manual (screen shot below) that it is either on or off, not dynamic (at least not today). Maybe in a future update...

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[HighTechLab]

EG4 6000XP Neutral-Ground Bonding

Let's start with a snip from the EG4 6000XP manual. What I'm getting at here, is a lot of people, including @Will Prowse in his latest video (8:03) are mistaken on how the 6000XP handles neutral and ground bonds. The inverter does NOT dynamically bond. This means that if you plan to put an...

diysolarforum.com

 

[Tripplett]

Rather than post a link it would have been helpful to also post points from that link.
So to save others the 15 minutes of time:

• You can use the Eg4's Chargeverter for charging. This won't help for passthrough though.
• You can use a 3rd party relay. There's some question if this is code compliant.
• You can hope EG4 adds a "dynamic" N-G bond later.
• You can have two N-G bonds (or none) - not advisable for proper breaker functionality.
• You can change the setting every time. Not practical, and won't work for dynamic passthrough.
• You can bring in the Neutral Ground bond from the home panel. I worry about grid backfeeding during grid down scenarios but probably ok.
• You should always have a ground. Good advice, but not relvant.

So while this is good information it didn't really answer the question.
Can we, like Will, bring just the L1, L2, and ground (no Neutral) from a main N-G panel into the 6000XP (that also has a N-G bond) for the passthrough and battery charging functions of the 6000XP?

 

[Will Prowse]

I was watching @Will Prowse latest video again on the 6000XP showing two units in parallel. In it at 6:06 he talks about the grid connections. He used a NEMA 6-50P plug to supply the Grid Input for the XP's pass through and battery charging. That plug doesn't carry a neutral wire. That makes sense because the 6000XP can't use a 120v feed for the grid in connection, it must be a 220v connection. Several of us have tested this.

So, given that, it seems like you could create a bond in the off grid panel or in the 6000XP AND have a Grid Input connection safely, without any unwanted neutral loops. No one is discussing this way of wiring the 6000XP.
The manual does say to "use a multimeter to confirm your AC Input lines (L1, L2, and neutral)" (screen shot below) so that implies it expects a neutral however I don't know why. I want to create the N-G bond at the off grid panel or at the inverter AND also have a 220v grid input for pass through/charging.
I'd love to hear other's thoughts on this.

Will also states @ 8:03 wrongly in the video that the 6000XP can dynamically switch the N-G bond based on if it is in pass through mode or not. That isn't the case based on everyone's testing that I've seen so far. And it even says in the manual (screen shot below) that it is either on or off, not dynamic (at least not today). Maybe in a future update...

View attachment 186410.





View attachment 186412

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I left in video because in parallel mode it does create appropriate ground neutral bond but doesn't create one dependent on if it is connected to grid or not. That's why I added a ground neutral bonding guide on my schematic page that covers this. Nice catch!

 

[Tripplett]

Thanks Will, I read through that page and the neutral ground discussion. But that still doesn't answer the question.

From a main house N-G bonded panel - can we just use L1, L2, and a ground for the Grid Input connection of the 6000XP, as you have done with a NEMA 6-50P (no Neutral connection back to the main house panel)? The 6000XP can't use the Neutral from that panel anyway since it requires a 220v Grid In connection.

If so then the inverter or "off grid" panel can handle the N-G bond. If not then it is better to bring in the Neutral with the Grid input and let the main house panel handle the N-G bond. Thanks.

 

[HighTechLab]

From a main house N-G bonded panel - can we just use L1, L2, and a ground for the Grid Input connection of the 6000XP, as you have done with a NEMA 6-50P (no Neutral connection back to the main house panel)? The 6000XP can't use the Neutral from that panel anyway since it requires a 220v Grid In connection.

No, especially with a NEMA 6-50P or a NEMA 14-50P. The only way to do it right is to hardwire it into the panel and run 4 wires to the inverter (L1, L2, N, G). It is not possible to safely install this inverter on a cord-and-plug because the cord and plug removes your N-G bond. That's the point of the whole post I linked.

 

[Tripplett]

It is not possible to safely install this inverter on a cord-and-plug because the cord and plug removes your N-G bond.

So the way @Will Prowse shows in the video, and the pictures on the blueprint are both wrong then. To be fair Will did say he didn't recommend doing what he did. In the video he doesn't mention usage of a neutral for the grid connection, but he also didn't use one. In the N-G bond discussion of the blueprint he does say to disable the bond if connecting to the grid permanently.


I also don't see how the inverter can use the Neutral from the house panel. It's similar to installing an EV charging plug. You don't need the neutral because the charger wants 220v and the neutral only is used for 110v loads. Most installers will land it in the plug anyway especially for a 14-50, but it isn't necessary to power the 220v load.

I'll just bring over the house main panel Neutral from the Grid Input and disable it in the inverter, but I still wanted to start the discussion to get feedback from the forum.

 

[HighTechLab]

The inverter system is not a pure 240v load. Whatever 120v loads are put on the load size get fed through when the inverter is in passthrough mode - thus you need a neutral connection. With the inverter's internal relay disabled, any ground faults in inverting mode are cleared via the neutral-ground bond in the main panel.

In other words, if you have a ground fault in inverting mode with the relay disabled, the current will flow back to the main panel on the grounding conductor, through the bond, and back to the inverter on the neutral conductor creating enough fault current to trip the appropriate overcurrent protection devices.

It should make more sense now how having a cord and plug between the inverter and the main panel that could arbitrarily be unplugged creates a dangerous situation; the fault current path is broken and exposed components become energized.

 

[Quattrohead]

In the first version of the video, Will used the ground connection as the neutral too. It works just fine but is not code compliant due to possible return current on the ground wire.
This is how all dryers in the USA used to be run, but NEC updated the requirements to make things safer.
As I have said sooo many times now, just because something works does not mean it is safe to use.

 

[Quattrohead]

It should make more sense now how having a cord and plug between the inverter and the main panel that could arbitrarily be unplugged creates a dangerous situation; the fault current path is broken and exposed components become energized.

Do we know if there is any AC or DC voltage on the pins of a plug if one used as a temporary input connection method to the 6000XP ?

 

[HighTechLab]

Do we know if there is any AC or DC voltage on the pins of a plug if one used as a temporary input connection method to the 6000XP ?

If there is a device that has a filtering circuit (or an actual ground fault), there is certainly the possibility of having 120V from N to G on the plug, unless you manually go in and change the setting every time you unplug the cord. We are certainly ignoring any chance of code compliance at this point, however.

 

[Tripplett]

It should make more sense now how having a cord and plug between the inverter and the main panel that could arbitrarily be unplugged creates a dangerous situation; the fault current path is broken and exposed components become energized.

Oh maybe I wasn't clear... if I was NOT bringing in the man house panel's neutral then the N-G bond would be set to Enabled in the 6000XP or the ground screw inserted into the off grid panel. Plus I would be hardwiring L1 and L2, no plug.

If the inverter passes through 120v in passthrough mode then yes it needs the house's neutral. I mistakenly thought it only passed 220v and the 110v loads would be handled by each phase of the inverter's output.

I also didn't think about what could happen in a fault event. That makes more sense.

 

[Will Prowse]

So the way @Will Prowse shows in the video, and the pictures on the blueprint are both wrong then. To be fair Will did say he didn't recommend doing what he did. In the video he doesn't mention usage of a neutral for the grid connection, but he also didn't use one. In the N-G bond discussion of the blueprint he does say to disable the bond if connecting to the grid permanently.


I also don't see how the inverter can use the Neutral from the house panel. It's similar to installing an EV charging plug. You don't need the neutral because the charger wants 220v and the neutral only is used for 110v loads. Most installers will land it in the plug anyway especially for a 14-50, but it isn't necessary to power the 220v load.

I'll just bring over the house main panel Neutral from the Grid Input and disable it in the inverter, but I still wanted to start the discussion to get feedback from the forum.

View attachment 186420

Yeah like I said in the video, don't do it that way. And what's incorrect about the ground neutral recommendations on the website?

Something else that doesn't matter that much is it's not connected to grid. So again like I said in the video don't do it that way lol it's not even the grid

 

[Will Prowse]

Oh maybe I wasn't clear... if I was NOT bringing in the man house panel's neutral then the N-G bond would be set to Enabled in the 6000XP or the ground screw inserted into the off grid panel. Plus I would be hardwiring L1 and L2, no plug.

If the inverter passes through 120v in passthrough mode then yes it needs the house's neutral. I mistakenly thought it only passed 220v and the 110v loads would be handled by each phase of the inverter's output.

I also didn't think about what could happen in a fault event. That makes more sense.

But if you see something actually wrong in My schematic page ground neutral recommendation, please let me know.

 

[Will Prowse]

I'm pretty sure we've covered all of this in the thread the Dexter already linked.

 

[Will Prowse]

That's also why I removed the AC input conductors for my websites pictures:

 

[Will Prowse]

So the way @Will Prowse shows in the video, and the pictures on the blueprint are both wrong then. To be fair Will did say he didn't recommend doing what he did. In the video he doesn't mention usage of a neutral for the grid connection, but he also didn't use one. In the N-G bond discussion of the blueprint he does say to disable the bond if connecting to the grid permanently.


I also don't see how the inverter can use the Neutral from the house panel. It's similar to installing an EV charging plug. You don't need the neutral because the charger wants 220v and the neutral only is used for 110v loads. Most installers will land it in the plug anyway especially for a 14-50, but it isn't necessary to power the 220v load.

I'll just bring over the house main panel Neutral from the Grid Input and disable it in the inverter, but I still wanted to start the discussion to get feedback from the forum.

View attachment 186420

What do you disagree with:

 

[Tripplett]

And what's incorrect about the ground neutral recommendations on the website?

I wouldn't say it's wrong per se... just that the images show one thing and the directions, well there aren't any for the Grid connection until you get to the bottom Bonding section.

That's also why I removed the AC input conductors for my websites pictures:

Like you said you removed the grid from the pictures even. If someone later doesn't watch the video and only goes by the blueprints they could do it wrong. Hopefully they read the section on bonding as that would explain the Grid connection AND they should be reading and following the manual too.

What do you disagree with:

I don't disagree with any of the bonding section - it's all good Will. All this is easy to grasp if you just remember there can be only one N-G bond in any circuit and, as @HighTechLab said, you shouldn't be able to remove it easily with a plug, switch, etc.

I'm pretty sure we've covered all of this in the thread the Dexter already linked.

I'm trying to look at all sides of this, that's how I tend to learn and understand things, sorry. Ultimately I wanted to have an off grid system with it's own N-G bond and STILL be able to charge and have pass through from the grid. I saw a way to accomplish this with the same way you did in the video with the 6-50P (but I would hardwire, just no neutral). That is turning out to be overcomplicated... I'm just going to connect all 4 wires, L1 L2 Neutral and Ground, from the main house panel.

I was assured by my electrician that if the grid was down the inverter wouldn't send any objectionable current back to the grid. At worst it might make it to the transformer, not the best but far from the worst scenario. But most likely it wouldn't make it past the main grid panel.

 

[Quattrohead]

I was assured by my electrician that if the grid was down the inverter wouldn't send any objectionable current back to the grid.

The 6000XP cannot do this, it is an off-grid unit.
However, that does not mean it cannot use the grid to pass-through or charge with.
It is just like any other hard wired or plug-in device in your home in this respect.

 

[HighTechLab]

I wanted to have an off grid system with it's own N-G bond and STILL be able to charge and have pass through from the grid

This is not possible.

Meanwhile,

I wanted to have an off grid system with it's own N-G bond and STILL be able to charge and have pass through from the grid

this is possible. You just have to run a neutral and ground to the inverter and disable the bonding relay.

I was assured by my electrician that if the grid was down the inverter wouldn't send any objectionable current back to the grid.

Using the N-G bond in the main panel is not sending objectionable current back to the grid. In your typical US power system, there is no way technically to send objectionable current back to the grid. Generally speaking, objectionable current is not allowed whatsoever.