Contactor combiner = disconnecting means? (NEC 2014)

If I can revive this thread, I have a similar question. The way I'm reading 690.15(C), it seems that all combiner boxes have to be disconnecting, even if you have a SolarEdge with Rapid Shutdown kit installed. I've been hearing everyone talk about 690.12, but this seems equally as huge, and I haven't heard much about it. If I have a solution that doesn't need a disconnecting combiner box for Rapid Shutdown, do I still have to have a manual disconnect in or within 6' of the combiner? Does it pertain to pass thru boxes as well?
 

SolarPro

Senior Member
Location
Austin, TX
Looking at the definition of a dc combiner, you should not have to apply 690.15(D) to a pass-through box.

If you look at the evolution of Code requirements over several cycles, the Code-Making Panel is really encouraging installers to locate serviceable parts, like fuses, at ground-level. 690.15(D) is part of this larger trend. It is expensive to put a bulky disconnecting combiner on the roof. If you don't do any combining on the roof, you can use more compact equipment that (hopefully) reduces your costs. After all, many inverters have an inverter-integrated dc combiner.
 
Looking at the definition of a dc combiner, you should not have to apply 690.15(D) to a pass-through box.

If you look at the evolution of Code requirements over several cycles, the Code-Making Panel is really encouraging installers to locate serviceable parts, like fuses, at ground-level. 690.15(D) is part of this larger trend. It is expensive to put a bulky disconnecting combiner on the roof. If you don't do any combining on the roof, you can use more compact equipment that (hopefully) reduces your costs. After all, many inverters have an inverter-integrated dc combiner.
Thanks. So you are finding that non-disconnecting combiner boxes will be a thing of the past, unless an external disco is also used? This came up with a client who is subcontracting a 1000V 3-phase SolarEdge system. He wanted to do some combining on the roof, but the Midnite box he wanted to use wasn't available in 1000V. Their 1000V combiners are non-disconnecting, so technically can't be used in NEC2014 states. So for 1000V systems, it's just SolarBos and Bentek, as far as I can tell.
 

ggunn

PE (Electrical), NABCEP certified
Location
Austin, TX, USA
Occupation
Electrical Engineer - Photovoltaic Systems
Looking at the definition of a dc combiner, you should not have to apply 690.15(D) to a pass-through box.

If you look at the evolution of Code requirements over several cycles, the Code-Making Panel is really encouraging installers to locate serviceable parts, like fuses, at ground-level. 690.15(D) is part of this larger trend. It is expensive to put a bulky disconnecting combiner on the roof. If you don't do any combining on the roof, you can use more compact equipment that (hopefully) reduces your costs. After all, many inverters have an inverter-integrated dc combiner.
But some of those inverter integrated DC combiners have non-finger-safe fuse blocks and the DC disco is between the fuses and the inverter, so those fuses are not serviceable without another disco between them and the PV array.
 

SolarPro

Senior Member
Location
Austin, TX
Good point, Gordon. And that basically requires gear with redundant functionality, which isn't ideal. For example, the 690.12 equipment might open the PV source circuits on the roof at the push of a button, but wouldn't meet the manual open required in 690.15(D).

@SolarQueen, yes it does appear that disconnecting combiners are replacing standard combiners on rooftops. Check out this article: The Evolution of DC Combiners.
 

Andrew445

Inactive, Email Never Verified
Has there been any update on how most major AFCI combiner boxes comply with 690.17? I believe the discussion left off with the fact that this Normally Open contactor is not considered to be "manually operable" with a loss of power. You cannot manually separate/close the physical connection with this handle switch, so it is not code-compliant as written. Do I have this correct? (In my opinion the code intent is met, regardless)


Following this, is the installation required to comply with NFPA 70E 120.2(E)(6)? "Locks/tags shall be installed only on circuit disconnecting means. Control devices, such as pushbuttons or selector switches, shall not be used as the primary isolating device.”
 

Carultch

Senior Member
Location
Massachusetts
Has there been any update on how most major AFCI combiner boxes comply with 690.17? I believe the discussion left off with the fact that this Normally Open contactor is not considered to be "manually operable" with a loss of power. You cannot manually separate/close the physical connection with this handle switch, so it is not code-compliant as written. Do I have this correct? (In my opinion the code intent is met, regardless)


Following this, is the installation required to comply with NFPA 70E 120.2(E)(6)? "Locks/tags shall be installed only on circuit disconnecting means. Control devices, such as pushbuttons or selector switches, shall not be used as the primary isolating device.”
So you are telling me, that from a Murphy's law perspective, all the stuff on the market utilizing normally-open contactors, and only a control circuit OFF-switch, does not comply? A more serious disconnect is still required?
 

Andrew445

Inactive, Email Never Verified
So you are telling me, that from a Murphy's law perspective, all the stuff on the market utilizing normally-open contactors, and only a control circuit OFF-switch, does not comply? A more serious disconnect is still required?
i am saying that it looks like poor wording of the code has left these devices not in compliance, as it is written. I do believe the intent of the code is met, which should be enough for most reviewers/AHJ, but you could run into some sticklers.
 

SolarPro

Senior Member
Location
Austin, TX
Following this, is the installation required to comply with NFPA 70E 120.2(E)(6)? "Locks/tags shall be installed only on circuit disconnecting means. Control devices, such as pushbuttons or selector switches, shall not be used as the primary isolating device.”
NFPA 120.2 pertains to the application of Lockout/Tagout devices. I wouldn't read anything more into it than that.
 

jaggedben

Senior Member
Location
Northern California
Occupation
Solar and Energy Storage Installer
I suppose one could argue that the requirement is for a 'disconnecting means', and so as long as you can manually disconnect the conductors, it's not required that you also be able to manually close the circuit. It's a stretch though.

As far as NFPA 70E, I suppose it would depend on the actual construction of the manual means. What you're describing doesn't fit.
 

MechEdetour

Member
Location
NY, USA
So now that the first draft has been released, and by the looks of it resolves the issue that this thread seems to revolve around (for now), how would the resolution be enforced?

What I mean is, if a particular state adopted NEC 2014 (and for the sake of argument contactors were not allowed under that edition), but now manufacturers will offer a combiner under provisions for NEC 2017 (and this time a contactor is permitted in this regard), will the combiner designed around requirements to NEC 2017 be suitable in a state that is implementing 2014?

Obviously can't go back the other way, but I'd imagine a newer edition be better suited than what is adopted by the state at the time?
 
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