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Eg4 3000ehv voltage on neutral?

uncle.driftwood

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Joined
Dec 11, 2022
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Not wanting to hijack another members thread, I am experiencing something very peculiar with the 3000w inverter. System is completely off grid.

With no wires connected to any of the ac terminals, I get a reading of 71vac on the N-G ac out, and and 49vac on L-G ac out. L-N is 119vac.
And voltage carries to the ac input N and G terminals to about 63vac.

This can't be correct right?
If bonding and working properly, N-G should be near 0.

Signature Solar has emailed me saying it is normal and a non issue, but it causes phantom voltage to make lights not turn all the way off and weird surges.
 
Maybe try connecting it with the G to Earth ground rod. Also, what if you turn off the inverter (with all leads disconnected) and do a continuity test and see how many ohms from N to G maybe?
 
The earth ground rod didn't change much, luckily its been raining and was easy driving. SS emailed me and gave me the OK to open it up and remove or tighten the bonding screw, then I can bond either at the terminals with a jumper, or in the AC sub panel. Also waiting on the cable to be able to update the firmware.

Gotta love when you have to buy more things to do a necessary update
 
There are a couple of reasons for this.

Each AC port and PV input port has EMI filters with small capacitors (like 0.1 uF) from each L and N AC line to case ground. These caps will couple a small amount of current to chassis ground.

The inverter output is a floating H-bridge, meaning both the L and N are floating until you ground the neutral.

There are several areas creating stray capacitance between PCB metal planes and ground.

All this small capacitance to case will show up if you measure L or N to case without any neutral-ground bonding with a high input impedance AC volt meter.

If you put some resistance, like a 1k ohm resistor from N to G most of the voltage between N and G will disappear.

These EMI filters AC current leakage to ground can sometimes trip an input side GFCI breaker. This can be a problem with RV's when plugging into a shore power outlet with GFCI protection.
 
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Update: still no answer from signature solar. Last email was on Dec 15th, asking for the reasons as to why I was getting voltages where they shouldn't be. They told me to open it and remove the screw. (Shouldn't have to tamper with new equipment)

I had to purchase the cable to do a firmware update as instructed by one of their techs and it still causes lights to pulse very annoyingly.

The idle draw is around 70w. Which is absurd for the size of the unit I think. It uses more power than my full size fridge and freezer.

All in all, the system does work, but not as well as my old 12v (epever, ipower, battery evo) system did. I have the same loads and need to charge with the generator more often! Guess we're out here paying to be the guinea pigs on new tech and poor follow up service.
 
There are a couple of reasons for this.

Each AC port and PV input port has EMI filters with small capacitors (like 0.1 uF) from each L and N AC line to case ground. These caps will couple a small amount of current to chassis ground.

The inverter output is a floating H-bridge, meaning both the L and N are floating until you ground the neutral.

There are several areas creating stray capacitance between PCB metal planes and ground.

All this small capacitance to case will show up if you measure L or N to case without any neutral-ground bonding with a high input impedance AC volt meter.

If you put some resistance, like a 1k ohm resistor from N to G most of the voltage between N and G will disappear.

These EMI filters AC current leakage to ground can sometimes trip an input side GFCI breaker.
I have a similar issue. I have the 3000w growatt and solar in an ambulance. I am using the output of the growatt to power the shorepower of the ambulance. I have votage on both the line to ground 56v and neutral to ground 63 volts. Line to Neutral is 120vI have a gfci breaker on one of the outletts but it doesnt seem to be triggering it. Should I open the case of the Growatt and remove the screw to break the neutral ground bond? Or is this indicative of having a loose screw in the case that is supposed to provide a neutral ground bond?
 
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Update: still no answer from signature solar. Last email was on Dec 15th, asking for the reasons as to why I was getting voltages where they shouldn't be. They told me to open it and remove the screw. (Shouldn't have to tamper with new equipment)

I had to purchase the cable to do a firmware update as instructed by one of their techs and it still causes lights to pulse very annoyingly.

The idle draw is around 70w. Which is absurd for the size of the unit I think. It uses more power than my full size fridge and freezer.

All in all, the system does work, but not as well as my old 12v (epever, ipower, battery evo) system did. I have the same loads and need to charge with the generator more often! Guess we're out here paying to be the guinea pigs on new tech and poor follow up service.
What did you end up doing?
 
I have a similar issue. I have the 3000w growatt and solar in an ambulance. I am using the output of the growatt to power the shorepower of the ambulance. I have votage on both the line to ground 56v and neutral to ground 63 volts. Line to Neutral is 120vI have a gfci breaker on one of the outletts but it doesnt seem to be triggering it. Should I open the case of the Growatt and remove the screw to break the neutral ground bond? Or is this indicative of having a loose screw in the case that is supposed to provide a neutral ground bond?
You are missing the N/G bond, also.
 
It leaves you with zero protection.
Without a grounding system, there is nothing to protect you and your equipment from a short in your

I am fundamentally confused as to the Growatt 3000 inverter, the screws, and if removing them is bonding or debonding them.
I am placing this inverter into an ambulance, which already has an input for shore power, a breaker box, and a pass through inverter. I am just using the Growatt to supply the Ambulance shore power.
I am about to make the final connections when I put the cheap tester on the AC out of the inverter. it tells me I have a hot neutral. I check the voltage and sure enough, I do. I google all kinds of different youtube videos and find one where a guy reports a similar issue. He removes some screws and vwalla, no more problem, but he seems to think that he is "Unbonding" the neutral and the ground


In my ambulance, I can test the voltage provided by either the current underpowered inverter, or when it is being powered by shore power and there is no voltage on the neutral side. I just dont want to create problems by providing power to the ambulance to both the line and the neutral
 
I am fundamentally confused as to the Growatt 3000 inverter, the screws, and if removing them is bonding or debonding them.
I am placing this inverter into an ambulance, which already has an input for shore power, a breaker box, and a pass through inverter. I am just using the Growatt to supply the Ambulance shore power.
I am about to make the final connections when I put the cheap tester on the AC out of the inverter. it tells me I have a hot neutral. I check the voltage and sure enough, I do. I google all kinds of different youtube videos and find one where a guy reports a similar issue. He removes some screws and vwalla, no more problem, but he seems to think that he is "Unbonding" the neutral and the ground


In my ambulance, I can test the voltage provided by either the current underpowered inverter, or when it is being powered by shore power and there is no voltage on the neutral side. I just dont want to create problems by providing power to the ambulance to both the line and the neutral
I have the GW 3000 on my truck camper. I did not remove any bonding screw. Shore power cord is connected to inverter input.

When under inverter power, the unit should bond N-G automatically. My unit does. When on shore power and in bypass, the unit will unbond N-G.

First, disconnect all wires going into the unit on output and input or do not have input plugged in. Test for continuity between N and G terminals with the inverter off. If there is continuity, the unit has N-G bond. If the unit does not have continuity, then it should be returned as it will not bond N-G on inverter power. This is important because in a mobile application under inverter power it is floating system. N and G need to be bonded under inverter power in case there is a ground fault.

On shore power, the pedestal or outlet will provide the N-G bond. That is why the unit will remove the N-G bond for the inverter.
 
I am fundamentally confused as to the Growatt 3000 inverter, the screws, and if removing them is bonding or debonding them.
I am placing this inverter into an ambulance, which already has an input for shore power, a breaker box, and a pass through inverter. I am just using the Growatt to supply the Ambulance shore power.
I am about to make the final connections when I put the cheap tester on the AC out of the inverter. it tells me I have a hot neutral. I check the voltage and sure enough, I do. I google all kinds of different youtube videos and find one where a guy reports a similar issue. He removes some screws and vwalla, no more problem, but he seems to think that he is "Unbonding" the neutral and the ground


In my ambulance, I can test the voltage provided by either the current underpowered inverter, or when it is being powered by shore power and there is no voltage on the neutral side. I just dont want to create problems by providing power to the ambulance to both the line and the neutral
No matter what you do. You are providing power through the line and neutral. Bonding the neutral to ground creates the grounding system. If this inverter is plugged into the shore power connector. It needs to provide a ground. Without a N/G bond, it cannot do that.
Your video shows that it's providing a N/G bond when inverting. It is working as it should be.
 
On shore power, the pedestal or outlet will provide the N-G bond. That is why the unit will remove the N-G bond for the inverter.
I did test, and their is no continuity between ground and neutral when the inverter is off. Only when it is powered on is there continuity.

I think I remember testing the output of this inverter before with the tester, and it did not report a hot neutral, but I could have been plugged into the house AC in..

So the tester reporting a hot neutral, and seeing voltage on both the line-ground, and neutral-ground, is okay, it is working as it should?
 
There should be zero volts between neutral and ground, if it's working properly.
 
No matter what you do. You are providing power through the line and neutral. Bonding the neutral to ground creates the grounding system. If this inverter is plugged into the shore power connector. It needs to provide a ground. Without a N/G bond, it cannot do that.
Your video shows that it's providing a N/G bond when inverting. It is working as it should be.
Mine is behaving just like that one. This inverter is powering outlets through the "Pass Through" function of another inverter. I have checked the outlets of that inverter and it does not show any voltage between neutral and ground. Though once I use the growatt as the shore power it does. There does not seem to be any neutral ground bond in the ambulance panel that I can see, but the pass through inverter does have a ground wire coming off of the back of it and I imagine it goes to the chassis.
 
I have the GW 3000 on my truck camper. I did not remove any bonding screw. Shore power cord is connected to inverter input.

When under inverter power, the unit should bond N-G automatically. My unit does. When on shore power and in bypass, the unit will unbond N-G.

First, disconnect all wires going into the unit on output and input or do not have input plugged in. Test for continuity between N and G terminals with the inverter off. If there is continuity, the unit has N-G bond. If the unit does not have continuity, then it should be returned as it will not bond N-G on inverter power. This is important because in a mobile application under inverter power it is floating system. N and G need to be bonded under inverter power in case there is a ground fault.

On shore power, the pedestal or outlet will provide the N-G bond. That is why the unit will remove the N-G bond for the inverter.
Could I get you to test your voltage while inverting on battery power. From Neutral to Ground
 
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