[RE-wrenches] AFCI Solved, Wet rated wire

[William Miller]

Friends:

 

I found the problem:  There was a damaged wire immersed in water in the
conduit.  The voltage was fluctuating at the inverter end and solid at the
module end.  After testing the Isc a few times the conductor burned through
and I was able to pull one end out of the conduit.

 

So, the inverter was doing its job.  We still have some wire nut splices
which are working fine.  I will eliminate them once I replace all of the
wire, which is warranted since this is the second conductor failure.

 

The conductors are all TWHN-2 which are wet rated.  I need to upgrade to a
better conductor. I have never had this type of failure at any other
location.  I suspect I should consider USE-2.  I'd appreciate comments on
this subject.

 

My thanks to Steve Jefferson for personal attention to this problem and to
everyone who responded.

 

And lastly, I still wonder about the concept of "internally arcing" wire
nuts.  I wonder if there is any scientific basis for the claim.  I will not
be using them in PV circuits on general principles.  If I do need to splice
I will probably use a gangable tubular terminal block.  There are more parts
to this connector than a wire nut so maybe those might arc.  We will see.

 

William Miller

 

 

Gradient Cap_mini
Lic 773985
millersolar.com <http://www.millersolar.com/> 
805-438-5600

 

-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.re-wrenches.org/pipermail/re-wrenches-re-wrenches.org/attachments/20140626/2e1b4741/attachment-0001.html>
-------------- next part --------------
A non-text attachment was scrubbed...
Name: image003.jpg
Type: image/jpeg
Size: 1460 bytes
Desc: not available
URL: <http://lists.re-wrenches.org/pipermail/re-wrenches-re-wrenches.org/attachments/20140626/2e1b4741/attachment-0001.jpg>