Daryl,
The Romex is a pretty clear violation of 690.31. This and the Pasadena
fiasco that Peter Parish speaks of illustrates a very common problem
that we all have. When it comes to photovoltaics, most AHJs don't know
their A....thority from a hole in the ground.
Bob-O
On Mar 6, 2009, at 11:27 AM, Darryl Thayer wrote:
no I have not, however I have seen where an AHJ has allowed romex from
the array down to the inverter in the basement through the house, the
array wire to a 3r disconnect on the roof and plastic from the disco
to the building entrance in the attic. No metal conduit from the array
to the inverter occurred. your case the AHJ is over kill, in my case
is clear under protection, because the DC from solar can arc without
overcurrent protection helping at all.
Darryl
--- On Fri, 3/6/09, Peter Parrish <[email protected]> wrote:
From: Peter Parrish <[email protected]>
Subject: [RE-wrenches] Chimneys Rigid vs EMT
To: "'RE-wrenches'" <[email protected]>
Date: Friday, March 6, 2009, 12:55 PM
We have an interesting situation in the enclave of Pasadena,
CA.
(1) The Pasadena Building and Safety Department is
requiring the use of
rigid conduit (only) on any DC and AC runs for grid-tied PV
systems. They
specifically prohibit EMT, LFNC and LFMC. This requirement
applies to any DC
or AC runs on the roof, and it applies to any DC or AC runs
on exterior
walls.
They do not require the use of rigid conduit on A/C
equipment, lighting or
any other piece of equipment requiring exterior-mounted
conduit conveying
electrical power.
(2) They also disallow a rigid conduit run anywhere on the
exterior surface
of a chimney. Where a conduit run on an exterior wall
encounters a chimney,
they require that the conduit run follow the line where the
chimney meets
the wall/roof. This means up the wall, along the roof and
back down the
wall.
Although I think (1) is overkill, I will comply this once
and engage the AHJ
before the next job we have in this town; I have graver
reservations about
(2). I have lived over 50 years in California and I have
seen the results
severe earthquakes can have on residential chimneys. If the
chimney goes,
the first place it happens is on the unsupported portion
above the roof. The
next place the chimney fails is the higher portion,
attached to the building
frame. I think I can remember just one case where a chimney
failed within 3
feet of the foundation, and in that case most of the rest
of the structure
failed. Consequently if a chimney fails, there will be
hundreds of pounds of
brick raining down on the rigid conduit where it runs along
the chimney roof
interface.
I would argue that the safest place for a rigid conduit run
would be around
the chimney in the crawl space (if any) underneath the
house, attached to
floor joists. If that option is not available I would argue
for a run around
(and anchored to) the exterior chimney at about 2-3 feet
above grade.
Is item (2) essentially a B&S issue not addressed by
the Fire Department?
Has anyone encountered these sorts of requirements
elsewhere?
Comments?
- Peter
Peter T. Parrish, President
California Solar Engineering, Inc.
820 Cynthia Ave., Los Angeles, CA 90065
Ph 323-258-8883, Mobile 323-839-6108, Fax 323-258-8885
CA Lic. 854779, NABCEP Cert. 031806-26
[email protected]
_______________________________________________
List sponsored by Home Power magazine
List Address: [email protected]
Options & settings:
http://lists.re-wrenches.org/options.cgi/re-wrenches-re-wrenches.org
List-Archive:
http://lists.re-wrenches.org/pipermail/re-wrenches-re-wrenches.org
List rules & etiquette:
www.re-wrenches.org/etiquette.htm
Check out participant bios:
www.members.re-wrenches.org
_______________________________________________
List sponsored by Home Power magazine
List Address: [email protected]
Options & settings:
http://lists.re-wrenches.org/options.cgi/re-wrenches-re-wrenches.org
List-Archive: http://lists.re-wrenches.org/pipermail/re-wrenches-re-wrenches.org
List rules & etiquette:
www.re-wrenches.org/etiquette.htm
Check out participant bios:
www.members.re-wrenches.org
_______________________________________________
List sponsored by Home Power magazine
List Address: [email protected]
Options & settings:
http://lists.re-wrenches.org/options.cgi/re-wrenches-re-wrenches.org
List-Archive: http://lists.re-wrenches.org/pipermail/re-wrenches-re-wrenches.org
List rules & etiquette:
www.re-wrenches.org/etiquette.htm
Check out participant bios:
www.members.re-wrenches.org
