EG4 3000EHV Neutral Bond Grounding

Greg.atini

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Dec 3, 2022
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5
Hello,

I setup a system to provide battery backup for my furnace. Location is a remote cabin and grid power goes down a few times each winter.

I had a Xantrex 1000 kw Freedom XC which worked perfectly. However, it was too loud, and I found the EG4 3kEHV which is a better deal, so I upgraded.

The EG4 manual reads that the ground will switch to an internal neutral bond when in battery mode. But it does not seem to work. When running on grid power my furnace runs with zero problem. If I cut power to grid, the system switches to battery but my furnace does not run properly and gives a ground error via blinking lights on control board inside the furnace.

I setup as per EG4 manual, with AC output ground on designated screw on outside of inverter. When that did not work, I even tried splicing in a solid copper ground wire to furnace as that is how the Xantrex inverter was setup. Still not working.

Only other thing to try is switching to Romex solid copper wire as I am using a 10AGW stranded wire; but seems that should not make a difference.

I reached out to Signature solar asking if my unit might be defective or if the bonded switched ground does not support my application. No response after a week and some follow ups on my part.

Any insights/help welcome!

Thanks in advance,

Greg
 
Last edited:

FilterGuy

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The first thing to do is check for voltage between neutral and ground on the output while the inverter is in battery mode. If there is more than a volt or two, the internal dynamic bonding is not working correctly.

BTW: I assume you have not removed the bonding screw inside the inverter.
 

Greg.atini

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Dec 3, 2022
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5
The first thing to do is check for voltage between neutral and ground on the output while the inverter is in battery mode. If there is more than a volt or two, the internal dynamic bonding is not working correctly.

BTW: I assume you have not removed the bonding screw inside the inverter.
Thanks FilterGuy,

I have not removed any internal screws but will look for it to make sure it is not missing.
Today I will also do the test as suggested and report back.
 

Greg.atini

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Dec 3, 2022
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5
The first thing to do is check for voltage between neutral and ground on the output while the inverter is in battery mode. If there is more than a volt or two, the internal dynamic bonding is not working correctly.

BTW: I assume you have not removed the bonding screw inside the inverter.

I turned the AC input off at the panel and the inverter kicked over to battery mode. The voltage test between the white neutral and the green ground (attached to outside of inverter as per manual) is showing about 55v. Testing between black load and white neutral is showing 118v.
The neutral to ground test is far more than a volt or two, any ideas? Maybe I have a faulty unit?

I looked into areas where you attached AC input/output and DC battery input and did not see any screws that could be the bonding screw you mentioned. Also did not find any reference via a quick inet search or manual. I assume it is inside the inverter. I have not opened up the inverter for fear of making it hard to return, but I should check to see if the mentioned screw is missing yes?

Many thanks for the help!!
 
Last edited:

Greg.atini

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Dec 3, 2022
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final follow up post: Signature Solar sent me a new inverter. I just swapped it out and I now get zero volts when testing white neutral and ground on AC out in battery mode. Further testing shows my furnace will run on battery and system flawlessly switches between AC grid and battery without missing a beat on furnace.

Thanks to FilterGuy for the voltmeter check tip and it helped me fast tract issues with signature solar support when I finally was able to speak to them.

Last observation: I spoke to two different tech support people at Signature solar and both insisted I should have a sub panel for AC out between inverter and furnace. As I am running one appliance that is 300w on a 3,000w inverter I don't think this is an issue (I went with 3k inverter for future growth). I can see you would need a sub panel if you were spreading the load across multiple devices and even over distributing (as you don't use all devices at same time) similar to a main panel.

Greg
 

uncle.driftwood

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Joined
Dec 11, 2022
Messages
9
I'm glad this worked out for you. I'm having the same issue with the same system! Hopefully signature solar will get back to me this week. Sent in pictures and voltage readings.
 

uncle.driftwood

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Dec 11, 2022
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9
The fact that I'm getting 52Vac neutral to ground and 67Vac hot to ground is very peculiar. I spent the week searching the forum and internet and finally found this post today
 

benjuario

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Joined
Dec 15, 2022
Messages
2
I am also having the same issue on the same inverter V2 model 13.5 inch wide (early V1 model was 11.75 inch wide per EG4 website). I am getting 60-61 volts hot to ground and 58-59 volts neutral to ground. Mine was shipped in October when they came back in stock. Reported on Monday and waiting to hear back.
 

Hyde5477

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Joined
Aug 12, 2020
Messages
13
Hello,

I setup a system to provide battery backup for my furnace. Location is a remote cabin and grid power goes down a few times each winter.

I had a Xantrex 1000 kw Freedom XC which worked perfectly. However, it was too loud, and I found the EG4 3kEHV which is a better deal, so I upgraded.

The EG4 manual reads that the ground will switch to an internal neutral bond when in battery mode. But it does not seem to work. When running on grid power my furnace runs with zero problem. If I cut power to grid, the system switches to battery but my furnace does not run properly and gives a ground error via blinking lights on control board inside the furnace.

I setup as per EG4 manual, with AC output ground on designated screw on outside of inverter. When that did not work, I even tried splicing in a solid copper ground wire to furnace as that is how the Xantrex inverter was setup. Still not working.

Only other thing to try is switching to Romex solid copper wire as I am using a 10AGW stranded wire; but seems that should not make a difference.

I reached out to Signature solar asking if my unit might be defective or if the bonded switched ground does not support my application. No response after a week and some follow ups on my part.

Any insights/help welcome!

Thanks in advance,

Greg
Can you tell me what page in the manual it states that there is an internal switch for neutral and ground? I don't see that I'm my manual
 

FilterGuy

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We started getting similar reports on the 6500EX a week or two ago. Just today EG4 informed me that they are no longer shipping the 6500EX with the bonding screw. My guess is that they have made this change on all of the inverters. If that is the case, they have really screwed things up. There are many issues with not shipping with the screw that would apply to any of the dynamic bonding inverters. If you want to follow the discussion, check out this thread:


The first part of the thread we were speculating on what was going on. This post is where I reported what I heard from EG4.


Note that signature solar joined the conversation after my post. I PM'd them and they are supposed to call me tomorrow to discuss all of this. I will try to remember to ask if all of their inverters will have the bonding screw removed.
 

krytentv

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Oct 30, 2022
Messages
6
I have the EG4 3000 EHV-48 with a date of 8/22. Installed acording to dynamic bonding operation clearly stated in the April 22 manuel it came with.
When tested I had no N+G bond with 60 v AC on n+g. contacted support. over a week and no answer.
After reading Filterguy's above thread. I checked for the bonding screw, it is removed! Guess I found the problem.
this is not good at all and dangerous.
 

FilterGuy

What, me worry?
Joined
Nov 26, 2019
Messages
6,724
Location
Los Gatos CA
I have the EG4 3000 EHV-48 with a date of 8/22. Installed acording to dynamic bonding operation clearly stated in the April 22 manuel it came with.
When tested I had no N+G bond with 60 v AC on n+g. contacted support. over a week and no answer.
After reading Filterguy's above thread. I checked for the bonding screw, it is removed! Guess I found the problem.
this is not good at all and dangerous.
Yes, EG4 confirmed that all of their inverters are now shipping without the bonding screws.
 

PreppenWolf

Solar Addict
Joined
Oct 10, 2022
Messages
530
To me it seems the inverter should have an external NG bonding jumper. It could be near the AC In, so covered, but accessible at setup instead of being internal.

It's not clear at this moment if the units shipping without the screw have a completely different active bonding or neutral system from the older models that shipped with the screw.
 

benjuario

New Member
Joined
Dec 15, 2022
Messages
2
The bizarre part is that I have received conflicting info that all V2 models ship without the screw, but when I opened up the inverter (with permission from SS) it definitely has the neutral-ground bond screw installed. There are actually 3 screws in various spots on the board with a ground symbol, but the point is mine (8/22 build sticker) has all ground related screws installed and the internal neutral-ground switching is still not working in battery/PV mode. I am also getting AC voltage backfeeding between ground and to PV+/- lines and AC INPUT (not output) lines. Still no response from Signature Solar on what is happening, defective inverter or terrible design?! Do all non-isolated inverters leak/backfeed AC voltage to PV lines like this?
 

krytentv

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Joined
Oct 30, 2022
Messages
6
The bizarre part is that I have received conflicting info that all V2 models ship without the screw, but when I opened up the inverter (with permission from SS) it definitely has the neutral-ground bond screw installed. There are actually 3 screws in various spots on the board with a ground symbol, but the point is mine (8/22 build sticker) has all ground related screws installed and the internal neutral-ground switching is still not working in battery/PV mode. I am also getting AC voltage backfeeding between ground and to PV+/- lines and AC INPUT (not output) lines. Still no response from Signature Solar on what is happening, defective inverter or terrible design?! Do all non-isolated inverters leak/backfeed AC voltage to PV lines like this?
I just checked mine. I have 136 V AC between PV + and ground, 2.9 v AC PV- and ground.
working with Tech support as of this moring. will update.
 
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