Solar System G-N bond

[MisterMoSparky]

I attached some photos of an outdoor service we completed yesterday. We also replaced the indoor panel. Originally it was a standalone meter. We now have G-N bonded in the Meter Combo and G-N separated inside the home. Originally the solar setup this customer had there was a bonding screw in the AC disconnect and also a bonding jumper in the white box to the left. I showed my inspector this while he was looking at our work and asked his opinion. He said the neutral and grounds are already bonded in this junction box at the meter socket so he then proceeded to take out the bonding screw in the AC disconnect. I didn’t want to touch the other bonding jumper because this was another company’s work but I honestly don’t think it should be there. When the lineman went to put the meter socket back in I placed the white jumper into this small lug inside the utility portion that is bonded to the enclosure neutral and ground bar. Inspector advised me to do this instead of double tapping the neutral like the old set up was which I agree with.

 

[MisterMoSparky]

By the way we plan on extending the 1” liquid tight conduit around the new meter today since it clearly blocks the cover from going back on.

 

[MisterMoSparky]

I also don’t agree with the auxiliary electrode in their AC disconnect considering all the sensitive electronics involved with their solar setup.

 

[jaggedben]

This is the third thread on this topic in as many days...

Interconnected power production pv disconnect neutral size bonding

When getting into pv solar systems, apparently the service grounded conductor neutral is jumped from either the grounded conductor buss at the service panel or the neutral lug at the main meter to bond the pv system disconnect? How do you size this grounded jumper conductor terminating and...

forums.mikeholt.com

GEC at Fused disconnect for a Photovoltaic System

Would a GEC at the fused disconnect be required for a photovoltaic system if we are bonded at the fused disconnect? This would be for a supply side tap the fused disconnect would be our overcurrent protection device. And if it is required to have a separate GEC at the fused disconnect what code...

forums.mikeholt.com

I attached some photos of an outdoor service we completed yesterday. We also replaced the indoor panel. Originally it was a standalone meter. We now have G-N bonded in the Meter Combo and G-N separated inside the home. Originally the solar setup this customer had there was a bonding screw in the AC disconnect and also a bonding jumper in the white box to the left.

A bonding jumper in the Enphase Combiner? Really? It appears you removed that. Good.

I showed my inspector this while he was looking at our work and asked his opinion. He said the neutral and grounds are already bonded in this junction box

Which junction box?

at the meter socket so he then proceeded to take out the bonding screw in the AC disconnect.
As you will read in the other threads, I think he is wrong, and the fused disco for the solar should have an N-G bond. However his interpretation is about par for the course and no big reason to argue with him.

As you will read in the other threads, I think he is wrong, and the fused disco for the solar should have an N-G bond. However his interpretation is about par for the course. As long as you have an effective ground fault return path to the neutral bar in the main panel.

I didn’t want to touch the other bonding jumper because this was another company’s work but I honestly don’t think it should be there. When the lineman went to put the meter socket back in I placed the white jumper into this small lug inside the utility portion that is bonded to the enclosure neutral and ground bar. Inspector advised me to do this instead of double tapping the neutral like the old set up was which I agree with.

Where does that white jumper come from? Through the liquidtight and the meter adapter? What about the green wire going into the liquidtight at the disconnect, where does that go? It seems right to me, but I'm not totally clear.

 

[jaggedben]

I also don’t agree with the auxiliary electrode in their AC disconnect considering all the sensitive electronics involved with their solar setup.

I don't know why you're worried about the electronics. A GEC to the fused disco would comply with 250.64(D). (I seem to see it below the disco in the photo, but I don't see where it lands in the disco.) Is there actually a separate electrode? Or just a separate GEC to the same electrode as the service? If the former just bond the electrodes together at the ground, then it's not auxiliary anymore and your concerns about lightning can be lessened.

 

[MisterMoSparky]

I don't know why you're worried about the electronics. A GEC to the fused disco would comply with 250.64(D). (I seem to see it below the disco in the photo, but I don't see where it lands in the disco.) Is there actually a separate electrode? Or just a separate GEC to the same electrode as the service? If the former just bond the electrodes together at the ground, then it's not auxiliary anymore and your concerns about lightning can be lessened.

The #6 copper GEC the solar company put in place is going to a ground rod directly below the fused AC disconnect. Not bonded to my #4 ground or my ground electrode. Mike holt’s video about PV systems explained that with a voltage gradient outside it will travel up through the #6 and then through the solar setup and find its way back down my #4 gec.

 

[MisterMoSparky]

This is the third thread on this topic in as many days...

Interconnected power production pv disconnect neutral size bonding

When getting into pv solar systems, apparently the service grounded conductor neutral is jumped from either the grounded conductor buss at the service panel or the neutral lug at the main meter to bond the pv system disconnect? How do you size this grounded jumper conductor terminating and...

forums.mikeholt.com

GEC at Fused disconnect for a Photovoltaic System

Would a GEC at the fused disconnect be required for a photovoltaic system if we are bonded at the fused disconnect? This would be for a supply side tap the fused disconnect would be our overcurrent protection device. And if it is required to have a separate GEC at the fused disconnect what code...

forums.mikeholt.com

A bonding jumper in the Enphase Combiner? Really? It appears you removed that. Good.



Which junction box?


As you will read in the other threads, I think he is wrong, and the fused disco for the solar should have an N-G bond. However his interpretation is about par for the course. As long as you have an effective ground fault return path to the neutral bar in the main panel.


Where does that white jumper come from? Through the liquidtight and the meter adapter? What about the green wire going into the liquidtight at the disconnect, where does that go? It seems right to me, but I'm not totally clear.

From the fused disconnect there’s x4 6AWG conductors traveling through the liquid tight into a junction box attached the meter socket extension. Inside the meter socket junction box there’s L1-L2 and then two lugs bonded together for G-N which then connect to that white jumper which is then connected to the main service disconnect neutral. I’m sorry I didn’t get a picture before POCO closed it.

 

[MisterMoSparky]

“As you will read in the other threads, I think he is wrong, and the fused disco for the solar should have an N-G bond. However his interpretation is about par for the course. As long as you have an effective ground fault return path to the neutral bar in the main panel.”

The solar setup in my opinion a separately derived system because it’s not back feeding anything inside the main indoor panel. It’s simply another source of power from its own starting point. I don’t know enough about solar to determine what the first point of disconnect is in their setup if it is a SDS like I’m assuming. Is it inside the solar enphase combiner or is it the fused AC disconnect or is it in the junction box of the meter socket or is it sharing the same common point as the utility neutral coming in?

 

[jaggedben]

From the fused disconnect there’s x4 6AWG conductors traveling through the liquid tight into a junction box attached the meter socket extension. Inside the meter socket junction box there’s L1-L2 and then two lugs bonded together for G-N which then connect to that white jumper which is then connected to the main service disconnect neutral. I’m sorry I didn’t get a picture before POCO closed it.

Got it.
It would be interesting to see the install instructions for that meter socket adapter and if they say that's how to do it. Without seeing them, I would prefer to see no green wire landed in that socket adapted, and a bonding screw or jumper in the disconnect. I think what you and the inspector did is also fine though. There should only be one bond, in one place or the other.

 

[MisterMoSparky]

This is the third thread on this topic in as many days...

Interconnected power production pv disconnect neutral size bonding

When getting into pv solar systems, apparently the service grounded conductor neutral is jumped from either the grounded conductor buss at the service panel or the neutral lug at the main meter to bond the pv system disconnect? How do you size this grounded jumper conductor terminating and...

forums.mikeholt.com

GEC at Fused disconnect for a Photovoltaic System

Would a GEC at the fused disconnect be required for a photovoltaic system if we are bonded at the fused disconnect? This would be for a supply side tap the fused disconnect would be our overcurrent protection device. And if it is required to have a separate GEC at the fused disconnect what code...

forums.mikeholt.com

A bonding jumper in the Enphase Combiner? Really? It appears you removed that. Good.



Which junction box?


As you will read in the other threads, I think he is wrong, and the fused disco for the solar should have an N-G bond. However his interpretation is about par for the course. As long as you have an effective ground fault return path to the neutral bar in the main panel.


Where does that white jumper come from? Through the liquidtight and the meter adapter? What about the green wire going into the liquidtight at the disconnect, where does that go? It seems right to me, but I'm not totally clear.

Also I did not remove any jumpers in the combiner, my AHJ simply removed the bonding jumper in the fused disconnect.

 

[jaggedben]

The solar setup in my opinion a separately derived system because it’s not back feeding anything inside the main indoor panel. It’s simply another source of power from its own starting point. I don’t know enough about solar to determine what the first point of disconnect is in their setup if it is a SDS like I’m assuming. Is it inside the solar enphase combiner or is it the fused AC disconnect or is it in the junction box of the meter socket or is it sharing the same common point as the utility neutral coming in?

It's not a separately derived system at all. It doesn't meet the definition. Separately derived systems have no direction connections between circuit conductors at all. Here the solar system is connected to the same service and the same service conductors.

So, the 'first' point of disconnect for the solar system is the fused disconnect. Because that's the closest point to the utility where you can disconnect it.

As I said in the other thread, for grounding and bonding purposes it's best to completely ignore that energy will flow from the solar system to the service in the opposite direction of normal loads. The utility is still the source of major fault current and the only thing that will trip any breakers, since the solar output is limited to less than its overcurrent devices. All of the grounding and bonding safety considerations are the same as if the solar system was a load. Only the rules are a little unclear and people are confused because of the history of different code making panels tussling over this turf.

 

[jaggedben]

Also I did not remove any jumpers in the combiner, my AHJ simply removed the bonding jumper in the fused disconnect.

Originally you said there was jumper in the 'white box to the left', I thought you meant the combiner. There is normally no neutral to ground jumper in an Enphase combiner.

 

[tortuga]

I have never seen a meter socket adapter like that, does the utility provide that ?
I would have just put a breaker in that spare spot in the panel and landed on that (making sure there was a 200A main inside).
Also how is that surge protector terminated on the side of the enclosure?

 

[MisterMoSparky]

I have never seen a meter socket adapter like that, does the utility provide that ?
I would have just put a breaker in that spare spot in the panel and landed on that (making sure there was a 200A main inside).
Also how is that surge protector terminated on the side of the enclosure?

The Lineman that came to disconnect and reconnect for us said he’s never seen this before and it was existing when I showed up to install the service. If you open the adaptor there’s also a 70Amp breaker inside of it as well. I’m heading back there today to extend the liquid tight so hopefully I can get some better pictures. Our surge protector we install won’t fit correctly on the bottom of the Eaton meter combos without blocking the sliding cover. It comes with a 1/2” nipple and a built in gasket so I drilled a 1/2” hole on the side and slide a lock it and terminate on the 30A breaker inside the meter combo.

 

[MisterMoSparky]

Originally you said there was jumper in the 'white box to the left', I thought you meant the combiner. There is normally no neutral to ground jumper in an Enphase combiner.

There is a conductor traveling from where the 6AWG neutral is bonding the 6AWG equipment ground bar. The white box I’m talking about is the farthest box on the left where the EMT exits and travels up the roof. Just so I don’t make the conversation more muddy,

There is EMT coming down from the roof solar panels traveling into the white box (ground and neutral bonded). From there it travels into the solar meter (ground and neutral separated). Then into the AC disconnect (originally ground and neutral bonded before the inspector removed the screw). Then travels through the liquidtight into the utility meter adaptor aka the junction box found on top of the meter socket (ground and neutral bonded). The single white conductor coming out of the meter adaptor is then traveling to the utility neutral bar (ground and neutral bonded). My 200A feeder wires travel into the house to the inside panel. (Ground and neutral separated)

I’m heading there now to extend the 1” liquid tight and I will have more pictures.

 

[MisterMoSparky]

It's not a separately derived system at all. It doesn't meet the definition. Separately derived systems have no direction connections between circuit conductors at all. Here the solar system is connected to the same service and the same service conductors.

So, the 'first' point of disconnect for the solar system is the fused disconnect. Because that's the closest point to the utility where you can disconnect it.

As I said in the other thread, for grounding and bonding purposes it's best to completely ignore that energy will flow from the solar system to the service in the opposite direction of normal loads. The utility is still the source of major fault current and the only thing that will trip any breakers, since the solar output is limited to less than its overcurrent devices. All of the grounding and bonding safety considerations are the same as if the solar system was a load. Only the rules are a little unclear and people are confused because of the history of different code making panels tussling over this turf.

That makes sense I’m sorry for my interpretation. Solar is very foreign to me and I would like to understand better as to be better prepared the next time I run into a situation like this and I can inform my AHJ.

 

[ggunn]

There is EMT coming down from the roof solar panels traveling into the white box (ground and neutral bonded). From there it travels into the solar meter (ground and neutral separated). Then into the AC disconnect (originally ground and neutral bonded before the inspector removed the screw).

IMO, the inspector removed the wrong N-G bond.

 

[MisterMoSparky]

IMO, the inspector removed the wrong N-G bond.

Sorry about the poor quality but correct me if my wrong the Ground and Neutral are bonded here?

 

[jaggedben]

Sorry about the poor quality but correct me if my wrong the Ground and Neutral are bonded here?

No. That's some kind of surge protector or ride through power capacitor for the Envoy, I'm honestly not sure of its function. But you can assume that the ground and neutral terminals have separate connections to that circuit board, just like the terminals on the Envoy circuit board up top.

 

[jaggedben]

... If you open the adaptor there’s also a 70Amp breaker inside of it as well. ...

Then that would be the first disconnect for the solar system. Unless it isn't accessible with the meter installed? Weird.

IMO, the inspector removed the wrong N-G bond.

I would have agreed until he mentioned the 70A breaker. Now I'm not sure.