[RE-wrenches] Wet locations: (was Push-in Wire Connectors)

Sun Oct 23 09:41:08 PDT 2011

I don't think the goo filled wire nuts are a problem, it would just prevent
corrosion from entering into the connection a few years down the road.  

Remember that we are supposed to have a solid mechanical connection before
we put on the wire nut. I always look at it as the nut just keeps me from
hitting the bare wire ends, not from keeping them from coming apart.

Bob Ellison

From: re-wrenches-bounces at lists.re-wrenches.org
[mailto:re-wrenches-bounces at lists.re-wrenches.org] On Behalf Of William
Miller
Sent: Friday, October 21, 2011 7:32 PM
To: RE-wrenches
Subject: Re: [RE-wrenches] Wet locations: (was Push-in Wire Connectors)

Ray/Jamie:

I think that a 3R installation may be superior to a Nema 4.  With a 3R any
condensation build up can drain.

Thanks to all of you for another round of thoughtful, well informed,
technical discussion.  This forum is very helpful and I really feel a lot of
camaraderie even though we are interfacing on a text basis.

William Miller

At 04:08 PM 10/21/2011, you wrote:

I started using the wet rated wire nuts, because I've found some corrosion
in old connectors in outdoor boxes. BTW, why don't you like the goo filled
wire nuts? They seem a decent and cost effective solution.
 I agree with your idea that condensation and moisture buildup can occur
even in a NEMA 4 box, and the issue that I have is that breakers and fuse
holders in combiner boxes are definitely not wet rated. I wonder what
happens to the internal workings of a breaker after decades in an outdoor
box, but considering there are an awful lot of them around (at least AC) I
guess I'll get  another night's sleep in our less than perfect world of PV
wiring.

Ray

On 10/21/2011 9:05 AM, Jamie Johnson wrote: 

William, the only explanation that I have found for using THWN-2 in conduit
run through the attic is that during the day as the temperature in the attic
increases, the air in the conduit expands, at night the opposite effect
happens, the temperature in the attic decreases and the volume of air in the
conduit contracts with the potential to bring in what ever climate
conditions exist outside the conduit (In FL this could be humid air).

Over time if there is humid air present, this could form condensation in the
conduit or NEMA 4 rated enclosure, hence the need for wire and connections
rated for a wet location.

I have seen photos at inspectors meetings of NEMA 4 enclosures and conduit
that contained water although I am not sure how often this would normally
happen.

Jamie Johnson
NABCEP Certified PV Technical Sales Professional
NABCEP Certified Solar PV Installer

General Manager
SOLAR POWER ELECTRIC
988e514.jpg

-------- Original Message --------
Subject: [RE-wrenches] Wet locations: (was Push-in Wire Connectors)
From: William Miller <william at millersolar.com>
Date: Fri, October 21, 2011 10:51 am
To: RE-wrenches <re-wrenches at lists.re-wrenches.org>

Friends:

I have had plan checkers insist I use wet rated wire on rooftops even though
the wire was in either liquid tight or EMT with raintight connectors.  I did
not need to dispute this because we had specified THHN wire that is also
rated THWN for wet locations.  This discussion makes me think I should have
contradicted the requirement because I am not sure wet rated wire is
required inside dry conduit.  I will be looking this up.

I feel that you should not let an AHJ impose a requirement that is not in
the code because then you become bound to the new stricture.  I realize that
an AHJ can impose stricter requirements, but I insist that it be in writing,
required in advance of the job in question and that it be required
universally.  Otherwise, it's anarchy.

William Miller

Miller Solar
Voice :805-438-5600
email: william at millersolar.com
http://millersolar.com <http://millersolar.com/> 
License No. C-10-773985

  _____  

_______________________________________________
List sponsored by Home Power magazine

List Address: RE-wrenches at lists.re-wrenches.org

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:
RE-wrenches at lists.re-wrenches.org

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: RE-wrenches at lists.re-wrenches.org

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 <http://www.members.re-wrenches.org/> 

No virus found in this incoming message.
Checked by AVG - www.avg.com <http://www.avg.com/>  
Version: 8.5.454 / Virus Database: 271.1.1/3962 - Release Date: 10/19/11
14:06:00

Miller Solar
Voice :805-438-5600
email: william at millersolar.com
http://millersolar.com <http://millersolar.com/> 
License No. C-10-773985

-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.re-wrenches.org/pipermail/re-wrenches-re-wrenches.org/attachments/20111023/0ae6ad85/attachment-0004.html>
-------------- next part --------------
A non-text attachment was scrubbed...
Name: image001.jpg
Type: image/jpeg
Size: 12045 bytes
Desc: not available
URL: <http://lists.re-wrenches.org/pipermail/re-wrenches-re-wrenches.org/attachments/20111023/0ae6ad85/attachment-0004.jpg>