110.26(A)(1) enphase microinverter combiner panel exemption

[Doctorman]

I have my main solar disconnect in my main service panel in garage.
In the attic in a tight space My combiner panel gets all the wires from the solar arays with 20amp breakers per array and a 100amp main breaker and send the power to my main disconnect in garage.

Failed final inspection because inspector asked for required panel clearance which I assume is referring to NEC 110.26(A)(1).


considering I have main disconnect in garage, shouldn't the combiner panel be exempt from 110.26(A)(1) clearance requirements? Enphase installation for their combiner box only suggests 12" clearance which makes me believe that combiner panel that can be fully de-energized from elsewhere should not need clearance.

 

[Doctorman]

the microinverters are Enphase M215

here is a combiner box installation box from enphase showing location requirment not matching NEC 110.26

https://www4.enphase.com/sites/default/files/downloads/support/IQ-Comb-3-Install-Guide-EN-US.pdf

 

[jaggedben]

You're gonna have to do what the inspector says on this. The combiner is basically a subpanel and any subpanel would be subject to 110.26. Manufacturers requirements may be less or more than code requirements. The instructions you posted also contain a sentence at the beginning stating you should comply with national and local codes.

 

[curt swartz]

I agree with the inspector.

 

[Doctorman]

it is very hard to move the panel,

so this argument would not fly:>

The combiner panel/box does not require examination, adjustment, servicing, or maintenance while energized per manufacturers installation guidelines and can be fully deenergized using the solar AC disconnect in the main panel, Therefore, the clearance requirements are not dictated by NEC 110.26.

 

[jaggedben]

No. In general equipment can require examination while energized during troubleshooting, for example measuring voltages. If you ever have to trouble shoot the individual circuits in the combiner it would be the same thing.

 

[Fred B]

I have my main solar disconnect in my main service panel in garage.
In the attic in a tight space My combiner panel gets all the wires from the solar arays with 20amp breakers per array and a 100amp main breaker and send the power to my main disconnect in garage.

Failed final inspection because inspector asked for required panel clearance which I assume is referring to NEC 110.26(A)(1).


considering I have main disconnect in garage, shouldn't the combiner panel be exempt from 110.26(A)(1) clearance requirements? Enphase installation for their combiner box only suggests 12" clearance which makes me believe that combiner panel that can be fully de-energized from elsewhere should not need clearance.

Inspector correct, the combiner is not just a jbox that get all the wires brought into. The presence of the overload protection require access and clearance of any other breaker panel.
The 12" reference in the instructions is in reference only the minimum hight off grade indoors, not clearances, in same paragraph it also states that the combiner be installed in a "readily accessible place". Your comment above "in the attic in a tight space" would be neither readily accessible or having appropriate workspace.
Just a side point, if attic is as described, it is likely not conditioned for temperature and likely will be VERY hot and VERY cold seasonally, and the breakers and electronics do not tolerate extreme conditions very well.

it is very hard to move the panel,

That isn't the concern of the inspector, if the conditions of the code are not met by current installation it fails and would need to be modified to be compliant.
Many times as installers and electricians we may neglect to review or by a simple oversight miss hitting an install correctly and need to "fix it" and how easy it is, is irrelevant to meeting code (even though might be relevant to guy doing work). I just view these as "I'll remember never do that again" moments, even though don't like it in the moment.

I think if it was me doing inspection and had to climb through an attic hatch and crawl in 2ft of blown-in to get to a panel I'd fail it too. I'm also sure a service tech that might have to come back to fix the overheated panel electronics would be none to happy laying in insulation at a 140 deg to try and service it.

I've never seen an installation done that way. Was there even signage to indicate the combiner location being other than the obvious location near the service panel? Proper signage is another potential point of failure as well. Lots and lots of signage required for a solar installation.

 

[Doctorman]

No. In general equipment can require examination while energized during troubleshooting, for example measuring voltages. If you ever have to trouble shoot the individual circuits in the combiner it would be the same thing.

the panel is just acting like a junction box, it never needs any attention, according to manufacturer it can be replaced by a junction box, if I can show that this is ana optional extra safety that we put in so we dont have to bring all the wires to the main panel that should fit
" does not require examination, adjustment, servicing, or maintenance while energized " per NEC.

Inspector correct, the combiner is not just a jbox that get all the wires brought into. The presence of the overload protection require access and clearance of any other breaker panel.
The 12" reference in the instructions is in reference only the minimum hight off grade indoors, not clearances, in same paragraph it also states that the combiner be installed in a "readily accessible place". Your comment above "in the attic in a tight space" would be neither readily accessible or having appropriate workspace.
Just a side point, if attic is as described, it is likely not conditioned for temperature and likely will be VERY hot and VERY cold seasonally, and the breakers and electronics do not tolerate extreme conditions very well.

That isn't the concern of the inspector, if the conditions of the code are not met by current installation it fails and would need to be modified to be compliant.
Many times as installers and electricians we may neglect to review or by a simple oversight miss hitting an install correctly and need to "fix it" and how easy it is, is irrelevant to meeting code (even though might be relevant to guy doing work). I just view these as "I'll remember never do that again" moments, even though don't like it in the moment.

I think if it was me doing inspection and had to climb through an attic hatch and crawl in 2ft of blown-in to get to a panel I'd fail it too. I'm also sure a service tech that might have to come back to fix the overheated panel electronics would be none to happy laying in insulation at a 140 deg to try and service it.

I've never seen an installation done that way. Was there even signage to indicate the combiner location being other than the obvious location near the service panel? Proper signage is another potential point of failure as well. Lots and lots of signage required for a solar installation.

The panel is placed in a fully finished and Air conditioned attic , the height of the ceiling is 6.5 feet tall at the panel and it has 36" wide area to work at the level of the panel. the problem is the AC ducts below the panel level reduce that width to a bit less than 30" and reduce the heigh right infront of the panel as a 2 ducts pass on the floor. it is easily accessible otherwise with lights and air conditioning.


regardless the code is the code, black and white (almost) my only argument would be this sentence in NEC 110.26
"require examination, adjustment, servicing, or maintenance while energized is required by installation instructions or function"
1) the Panel was optional and it functions as a combiner or Junction box
2) the panel can be fully de-energized and there is no need according to the manufacturer to work on it while energized

Hence by function and installation instruction is does not require to be energized while working on it and is exempt from those exact measurements as long as it is easily accessible.

I guess if push comes to show I will just change it to a J-Box for inspection, while less safe, it should pass inspection. I hope I dont have to do that extra work to go backward.


For Reference:

NEC 2020 110.26

(A) Working Space. Working space for equipment operating at 1000 volts, nominal, or less to ground and likely to require examination, adjustment, servicing, or maintenance while energized shall comply with the dimensions of 110.26(A) (1), (A)(2), (A)(3), and (A)(4) or as required or permitted elsewhere in this Code

(4) Limited Access. Where equipment operating at 1000 volts, nominal, or less to ground and likely to require examination, adjustment, servicing, or maintenance while energized is required by installation instructions or function to be located in a space with limited access, all of the following shall apply:”

 

[Fred B]

the panel is just acting like a junction box, it never needs any attention, according to manufacturer it can be replaced by a junction box, if I can show that this is ana optional extra safety that we put in so we dont have to bring all the wires to the main panel that should fit
" does not require examination, adjustment, servicing, or maintenance while energized " per NEC.

The combiner you listed (post #2) is not a simple jbox, it has overcurrent as well as other circuitry within, and may need to be serviced or diagnostics performed while energized.

The panel is placed in a fully finished and Air conditioned attic , the height of the ceiling is 6.5 feet tall at the panel and it has 36" wide area to work at the level of the panel. the problem is the AC ducts below the panel level reduce that width to a bit less than 30" and reduce the heigh right infront of the panel as a 2 ducts pass on the floor. it is easily accessible otherwise with lights and air conditioning.

Also you've now changed the description of the space from a tight attic to a wide open finished space.
If this is a finished space how are ducts present in the way?

regardless the code is the code, black and white (almost) my only argument would be this sentence in NEC 110.26
"require examination, adjustment, servicing, or maintenance while energized is required by installation instructions or function"
1) the Panel was optional and it functions as a combiner or Junction box
2) the panel can be fully de-energized and there is no need according to the manufacturer to work on it while energized

Your statement #2 is such that if to use your reasoning can apply to ANY panel box, including a meter pan, you can always disconnect the power somewhere.

I guess if push comes to show I will just change it to a J-Box for inspection, while less safe, it should pass inspection. I hope I dont have to do that extra work to go backward.

Don't see how that would work, you have multiple inverters with wiring sized for their amperages and they go to a panelboard to splice with appropriate overcurrent protection on each then combining to a larger feeder that has it's own appropriate overcurrent protection to feed to the rapid shutdown and service panel. Elimination of the panels overcurrent would render the conductors unprotected and likely undersized.

 

[Doctorman]

The combiner you listed (post #2) is not a simple jbox, it has overcurrent as well as other circuitry within, and may need to be serviced or diagnostics performed while energized.

Also you've now changed the description of the space from a tight attic to a wide open finished space.
If this is a finished space how are ducts present in the way?

Your statement #2 is such that if to use your reasoning can apply to ANY panel box, including a meter pan, you can always disconnect the power somewhere.

Don't see how that would work, you have multiple inverters with wiring sized for their amperages and they go to a panelboard to splice with appropriate overcurrent protection on each then combining to a larger feeder that has it's own appropriate overcurrent protection to feed to the rapid shutdown and service panel. Elimination of the panels overcurrent would render the conductors unprotected and likely undersized.

Thank you.
Not sure if this would make a difference at all.
It's a finished attic but closed off a part for utility room. Anyway it seams like I have no argument left then. Have to pull the panel forward passed the ducts so I have nothing Infront of it...

 

[Doctorman]

can someone explain to me an example of a device does not need service while energized? what is this sentence excluding
"likely to require examination, adjustment, servicing, or maintenance while energized is required by installation instructions or function"

 

[jaggedben]

I think it's a bit vague and up to the AHJ to interpret. But usually a single light switch, fixture, or receptacle would be the only sorts of things to which it doesn't apply. The idea being you can turn off the single circuit elsewhere and it's a simple device. Wherever you have multiple circuits coming into equipment, or the equipment is complicated enough in function, 110.26 is goijng to apply. As I said above, it's generally understood that any panelboard with multiple overcurrent devices is subject to the rule and the combiner is a panelboard which just has a monitoring device attached.

 

[Doctorman]

would the box be considered exempt from 110.26 clearence if I remove the breakers and use it just as a junction box to extend the wires inside to a new panel location? does it have to be accesible as a junction box at all?

 

[wwhitney]

You could certainly put your combiner panel in a different compliant location, and put a junction box in your current combiner location.

But it sounds like the only issue is the duct at the floor level? Can you recess the duct, or pull the combiner panel forward so the duct is behind the plane of the face of the panel?

Cheers, Wayne

 

[Doctorman]

1 final thought before I get to the changes would this exception apply

"Exception No. 2: In existing dwelling units, service equipment or panelboards that do not exceed 200 amp,s shall be permitted in spaces where the height of the working space is less than 2.0m (6½ft)."

it is an existing residential that had renovation done, the solar panels are new install in an existing dewelling
I have 30" wide at the level of the panel and the door opens fully, I can cover the ducts to make a platform but I wont have 6 feet height then.

could not move the ducts, unfortunately.

You could certainly put your combiner panel in a different compliant location, and put a junction box in your current combiner location.

But it sounds like the only issue is the duct at the floor level? Can you recess the duct, or pull the combiner panel forward so the duct is behind the plane of the face of the panel?

Cheers, Wayne

pulling the box forward will not leave me exactly 30" wide opening because of the AC machine,


So to move the panel, can I leave the old panel in the wall as junction box and cover it with plywood or sheetrock? no access would be needed right?

and no more rough inspection, just move it and close it up all ready for final inspection, meaning inspectors wont need to see the wires I drew to the new panel in the wall?

 

[wwhitney]

Junction boxes have to be accessible, no burying. You could use the existing enclosure if you can easily get a new enclosure to swap all the combiner innards into. Otherwise I would think a junction box would be simpler.

Yes, if the dwelling unit is existing, then the Exception would allow the height to be under 2.0m. So you just need 30" wide x 36" deep, and the duct is the only issue.

I would say the better solution is to reconfigure the AC equipment as required: move the AC slightly, change the shape of the duct, move the panel forward, whatever it takes. But as you say those are all hard, here is an apparently allowable, but lame solution:

Build a 30" wide x 36" deep platform whose top is just above the duct, shrinking the headroom even more (but that's allowed by the exception). Might need a step or two to get to, hopefully there would be room. This assumes the duct is on the floor or can be lowered to be on the floor.

Cheers, Wayne

 

[Doctorman]

Junction boxes have to be accessible, no burying. You could use the existing enclosure if you can easily get a new enclosure to swap all the combiner innards into. Otherwise I would think a junction box would be simpler.

Yes, if the dwelling unit is existing, then the Exception would allow the height to be under 2.0m. So you just need 30" wide x 36" deep, and the duct is the only issue.

I would say the better solution is to reconfigure the AC equipment as required: move the AC slightly, change the shape of the duct, move the panel forward, whatever it takes. But as you say those are all hard, here is an apparently allowable, but lame solution:

Build a 30" wide x 36" deep platform whose top is just above the duct, shrinking the headroom even more (but that's allowed by the exception). Might need a step or two to get to, hopefully there would be room. This assumes the duct is on the floor or can be lowered to be on the floor.

Cheers, Wayne

Thank you so much for the help,
I was ready to move the panel and everything and got your post reply.
I will put up a small fight for this then and if the inspector does not allow it I will move it.
we failed when there was another round flexible duct that is now bent in the left from the AC machine going to the right in the wall.
that duct was obstructive and I have it removed easily.
at the level of the panel, you can see it is wide open, but just under the panel height, it drops down.
so for the exception of the height to work I have to have a platform built under the panel, I still prefer to do that than touch the panel, as the cables in the panel are not long enough to move.
The inspector did not quote the exact detail of the problem he has, he just wrote "Attic panel needs proper clearance"

So I will respond to him in multi-facet defense
1) The panel is a combiner and does not need to be energized when serviced. Per 110.26(4)(Limited access) the required clearance does not apply to such a device.
2) The main solar disconnect is located in the main panel in the garage to de-energize the whole solar system for service.
3) we have removed the duct obstructing the direct access to the panel and provided a platform to cover the ducts under the panel that will provide a space over 30" wide, over 36" deep, allowing access to the panel and the door of the panel to fully open, Per 110.26(A)(3)(Workplace Height-Exception No. 2) in existing dwelling and amperage of below 200amp the height minimum does not apply.

 

[wwhitney]

I don't see how you can make that location work, the panel needs to move.

Cheers, Wayne

 

[Doctorman]

I don't see how you can make that location work, the panel needs to move.

Cheers, Wayne

Because of the slope in the ceiling cutting into the width?

 

[Fred B]

The picture should have been given right off. The panel has to be moved. Inspector correct in calling it out.
Their is no way to make that location work even with the workaround given by Wayne now that we see a picture. IDK to start with who would have thought that this would be a good location, or how installing in that location was workable with all that HVAC equipment in the way. I certainly would never have wanted to struggle to put a panel up there.
Your 1st argument in post #17 is still wrong it doesn't matter that you can de-energize or not it is a breaker panel not just a junction box.

This picture makes me question, what was there first, the panel or HVAC?
If the panel was first you have an argument with the HVAC installer not the inspector. If however the HVAC was first, shame on the installer as that should have been recognized by the electrician as never compliant. (Let alone the real hassle to place it there, and to work on it.)

Simply if the panel was install to the picture right of the ducts I don't think the inspector would have had called out horizontal working space as an issue. If I could stand in front of the panel with nothing to climb over or to trip over to work on it horizontal space I would "let it go". Your excuse of that it can be de-energize would only make application of equipment dedicated space 110.26(E)(1) a workaround, and it would allow a narrower space for equipment, but all that "foreign" equipment located as installed is still a violation of that where the panel is now. There are 2 portions to 110.26, working space and dedicated equipment space.

That is not really a conditioned space as you mentioned in post #8, the sheetrock based on there being double layer on wall was meant as seperation for the attic mechanical room and no appearance of conditioned air for that space visually present, and actually would be not usually done, for the AC mechanical space, many times when I worked for a GC we would install a double layer as a fire barrier but the unsealed duct penetration invalidates that application.

Bottom line, something has to move.