[RE-wrenches] parallel OCPD

[mac Lewis]

Good points.  I would think a more dangerous situation would be the case
that you often have with large parallel feeders landing on a single OCPD.
 If one wire has a little less resistance, it will always run hotter than
the other, and you could easily overheat a wire that is protected by that
large OCPD.
Thanks

On Wed, Sep 26, 2012 at 6:48 AM, Jeff Irish <jeff at hudsonsolar.com> wrote:

>  Code issues aside, even two seemingly identical runs each with breakers
> would have at least slightly different resistances, causing the lower
> resistance run to take more than half the total current, tripping the
> breaker in that run, then causing a tripping of the breaker in the other
> run.****
>
> ** **
>
> Jeff Irish****
>
> ** **
>
> *From:* re-wrenches-bounces at lists.re-wrenches.org [mailto:
> re-wrenches-bounces at lists.re-wrenches.org] *On Behalf Of *mac Lewis
> *Sent:* Tuesday, September 25, 2012 9:16 PM
> *To:* RE-wrenches
> *Subject:* [RE-wrenches] parallel OCPD****
>
> ** **
>
> Hello wrenches,****
>
> ** **
>
> Does anyone understand why you are not allowed to have parallel separately
> protected runs of wire.****
>
> For example, say I need 120A from point A to point B, why doesn't the code
> allow two runs of #6 breakered at 60A each.  Its probably obvious, but not
> to me...****
>
>
> ****
>
> ** **
>
> -- ****
>
> ** **
>
> ** **
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> ** **
>
> Mac Lewis**
>
> "Yo solo sé que no sé nada." *-Sócrates***
>
> ** **
>
>
> --
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-- 



Mac Lewis

*

"Yo solo sé que no sé nada." -Sócrates
*
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