[RE-wrenches] Fastening of Backfed Breakers

[Jason Szumlanski]

This has reached a new level of misinterpretation. See my response and
inspector's further misinterpretation regarding fastening of breakers. I'm
at a loss of what to do now. I would just have the backfed breakers
fastened, but the clips can't be installed on adjacent breakers, so it's
impossible when you have more than one backfed breaker on one side of a
panelboard.

Am I missing something here?






On Wed, Nov 18, 2015 at 8:04 PM, Inspector Who Shall Not Be Named wrote:

Sorry I haven’t gotten back to you in a couple of days.



*2011 NEC Article 690.10 (E) says:*



*Back-fed Circuit Breakers.*  Plug-in type back-fed circuit breakers
connected to a stand-alone inverter output in either stand-alone or
utility-interactive systems shall be secured in accordance with 408.36(D).
Circuit breakers that are marked line or load shall not be backfed.



It is stand a stand alone output if it is not fed back into the meter.  It
is a utility interactive output if it is.  But either way the inverter
itself is stand alone unit.





*2011 NEC Article 705.12(D)(6) **says:*



*Fastening.*  *Listed plug-in type circuit breakers* backfed from
utility-interactive inverters that are listed and identified as interactive
shall be permitted to omit the additional fastener normally required by
408.36(D) for such applications.



As you can see it says LISTED PLUG IN TYPE CIRCUIT BREAKERS.  It also says
listed for the inverter but is needed is a listed breaker or it needs to be
a bolt in type.



These are the new NEC changes that are now in effect.




On Fri, Nov 13, 2015 at 4:24 PM, Jason Szumlanski <> wrote:
I think there are two sources of confusion here.

610.10(E) does not apply to the systems in question in any way. 610.10
applies only to breakers connected to a standalone inverter. The definition
of stand-alone system (690.2) is a system that operates independently of a
distribution network (utility). These systems are not stand-alone.

​​705.12(D)(6) says the inverter needs to be listed and identified as
interactive, not the breaker.




On Fri, Nov 13, 2015 at 5:05 PM, Jason Szumlanski <
jason at floridasolardesigngroup.com> wrote:

> NEC 2011 - one inspectors misinterpretation of the code below for your
> amusement and comments. I have to admit that 705.12(D)(6) is somewhat
> ambiguous. Appropriate use of commas by code writers would be very helpful.
> I was able to find Mike Holt's guide that clears it up, so hopefully that
> will do the trick.
>
>
> From the inspector:
>
> ​
> I am sending this e-mail to straighten out the confusion and lay out the
> requirements of the 2011 NEC requirements which now govern solar
> photovoltaic breaker requirements.
>
>
>
> Any back fed breaker is required to be secured in accordance with 2011 NEC
> 408.36 (D) which says:
>
>
>
> *Back-Fed Devices.*  Plug -in type overcurrent protection devices or plug
> in type main lug assemblies that are backfed and used to terminate field
> –installed ungrounded supply conductors shall be secured in place by an
> additional fastener that requires other than a pull to release the device
> from the mounting means on the panel.
>
>
>
> This is also reiterated in the solar photovoltaic article 2011 NEC 690.10
> (E) which says:
>
>
>
> *Back-fed Circuit Breakers.*  Plug-in type back-fed circuit breakers
> connected to a stand-alone inverter output in either stand-alone or
> utility-interactive systems shall be secured in accordance with 408.36(D).
> Circuit breakers that are marked line or load shall not be backfed.
>
>
>
>
>
> *NEC 2011 Article*
> *​​*
> *705.12(D)(6) does not say what you have sent.  This is what it says Word
> for Word:*
>
>
>
> *Fastening.*  Listed plug-in type circuit breakers backfed from
> utility-interactive inverters that are listed and identified as interactive
> shall be permitted to omit the additional fastener normally required by
> 408.36(D) for such applications.
>
>
>
> What this article says is that if the manufacturer has gotten his breaker
> UL listed and the breaker is identified as interactive it may be used
> without a hold down device.
>
>
>
> Again in conclusion a breaker may be used if it has been certified and
> listed by the manufacturer and is marked interactive.  If you can find a
> listed and interactive identified breaker then you may use it without
> having to secure it in place as required by 408.36(D).  All parties
> involved have been sent the above attached document which very nicely
> explains the new requirements but I will attach it again just in case you
> happened to have lost it.
>
>
>
> If anyone has anymore questions please feel free to contact me.
>
>
>
>
>
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