Looking for a breaker hold down solution

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solarnynja

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We build solar jobs and Sunnova is requiring all of our PV and Battery breakers be held down in the load center. They consider them back-fed breakers. The problem is, available load centers only allow one or two breakers to be held down. Most of the time we have up to four breakers such as a 2 battery 2 inverter system. I cannot find a solution. Have any of you out there come accross this and have a solution?
 
In no particular order:

1. Interlockkits used to come with a large cable-tie that was installed around the 2-pole generator breaker and the 2-pole (or two 1-pole breakers) opposite it. Inspector may accept this.

2. They now provide a sheet metal bracket that fits between the two breakers and the next ones down, gets screwed to the back of the panel, and has a tab that holds the breaker in place.

See video clip here: https://interlockkit.com/

3. Carefully drill a hole between the breaker bodies like this breaker has, drill an appropriate hole in the rail underneath, and install a sheet-metal screw like backfed-breakers come with:

BR Type 2 Pole Circuit Breaker | Shop Circuit Breakers | Metalworks ...
 
I have not heard of this especially since the hold down breaker spot is usually at the top of the panel. I believe solar breakers should be installed at the bottom of the busbar
 
Assuming we are talking about grid-tie only solar here, the solution is for Sunova to read 705.12(E)* and to stop being dumb.

(*2020 NEC reference. Numbering has changed over the last several code cycles but it's been in there somewhere the whole time.)
 
Dennis Alwon said:
I have not heard of this especially since the hold down breaker spot is usually at the top of the panel. I believe solar breakers should be installed at the bottom of the busbar
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They just need to be installed at the opposite end from the main supply, so that the loads are in between both sources, and current on the busbar is subtractive, rather than additive, in order to take credit for the 120% rule on a panel with loads. It's common that this means it is on the bottom, but on a bottom-fed panel, it would be on the top.

The rule the OP is questioning, is the requirement for the hold-down kit on a backfed breaker. This applies for backfed breaker, but grid tied inverter breakers have an exception, due to the fact that they are only grid-following, and not grid-forming. If you unplug the breaker, the grid ceases to be within spec, and the inverter(s) will shut down right way. The reason for the rule for a hold-down kit, is to prevent popping a breaker energized from its load side, which could still have voltage at its terminals after removal. Grid-tied inverters don't fit within this intent, since they are a current source that follows grid voltage, rather than a source that produces its own voltage.
 
Carultch said:
They just need to be installed at the opposite end from the main supply, so that the loads are in between both sources, and current on the busbar is subtractive, rather than additive, in order to take credit for the 120% rule on a panel with loads. It's common that this means it is on the bottom, but on a bottom-fed panel, it would be on the top.

The rule the OP is questioning, is the requirement for the hold-down kit on a backfed breaker. This applies for backfed breaker, but grid tied inverter breakers have an exception, due to the fact that they are only grid-following, and not grid-forming. If you unplug the breaker, the grid ceases to be within spec, and the inverter(s) will shut down right way. The reason for the rule for a hold-down kit, is to prevent popping a breaker energized from its load side, which could still have voltage at its terminals after removal. Grid-tied inverters don't fit within this intent, since they are a current source that follows grid voltage, rather than a source that produces its own voltage.
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This particular installation method is a 125 amp 8/16 nema 3 load center with 4 two pole breakers installed. These are ESS systems and each breaker is considered backfed.
 

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Okay my assumption was wrong, somehow I overlooked the word 'battery' in the OP.

I think Eaton BR is your best bet but I can't tell you a model number for a panel. You might have to go to bolt-on breakers to have a listed solution.

They are still wrong if they are asking for them on the solar inverter breakers. Only the Powerwalls need hold-downs.
 
jaggedben said:
Okay my assumption was wrong, somehow I overlooked the word 'battery' in the OP.

I think Eaton BR is your best bet but I can't tell you a model number for a panel. You might have to go to bolt-on breakers to have a listed solution.

They are still wrong if they are asking for them on the solar inverter breakers. Only the Powerwalls need hold-downs.
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I agree. but the AHJ in this situation, is sunnova. They’re like the solar mafia. If you don’t do what they say, you don’t get paid. I’m leaning towards the pow-r-line panel with BAB breakers. If only I could find it in Nema 3
 
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