Hi Dana,
Sorry for the delay - been on the road. Not sure if this has already
been presented / discussed.
The old standby from industrial chargers, is 100% SOC is reached when
charge current drops to 2% of capacity (normaly based on 6 or 8 hr
rate). Please note, this comes from an era of
All,
For longer, underground, array to inverter/charge controller runs, are folks
using aluminum or copper?
Last time I compared prices, for the same ampacity, Al was 1/3 the cost of Cu.
Dick Ratico
Solarwind Electric
--- You wrote:
Hi Dana;
I'd say that's a bit overkill for today's market.
I found similar to Phil, but all the wire had thwn-2 on the spool label but not
on the wire.
Execpt for pink it did not have thwn-2 on the spool lable.
Darryl
--- On Fri, 7/23/10, Phil Undercuffler solarp...@gmail.com wrote:
From: Phil Undercuffler solarp...@gmail.com
Subject: Re:
I try to keep it in copper for DC, as I had always heard of trouble with
Aluminum on DC. (True or Old Wrenches Tale?)
We definitely go to Al on long AC runs, as its whats available, and the cost
difference becomes remarkable.
I've seen small cuts in Al, later corrode completely through the
We went through a similar problem with some beach communities here in SoCal.
Because of the high humidity (all winter and summer mornings) they wanted
THWN-2 for all conduit runs (as well as PVC instead of EMT). At first we
were charged a premium for THWN-2 compared to THHN. But then we found a
I have specified THWN-2 for years, but occasionally will not be able to source
it!
Sent from my iPhone
On Jul 23, 2010, at 11:37 AM, Peter Parrish peter.parr...@calsolareng.com
wrote:
We went through a similar problem with some beach communities here in SoCal.
Because of the high humidity
I'm sorry to broadcast my ignorance, but:
Could someone explain to me the significance of the -2 marking? Reply
off-list if you wish to save bandwidth...but other List members may also be
wondering...
Thanks,
Mick Abraham, Proprietor
www.abrahamsolar.com
Voice: 970-731-4675
On Fri, Jul 23,
-2 indicates that the insulation is rated for hot wet; that is that
it is rated for 90C and wet conditions. See NEC Table 310.13(A).
We also use Encore Wire. The sticker on the spool has THHN in big
print, but then in small print below it says Type MTW or THHN or
THWN-2. The insulation
Mick,
THWN-2 is 90°C rated per Table 310.16. This is key for conductors in conduit
on a roof. On a roof in full sun ambient temperatures are such that a 75°C
rated conductor will have a severely diminished allowable ampacity, if any
allowable ampacity.
Jollily,
David
On 7/23/10 11:52 AM, Mick
The dash-two, as an appendage to THWN indicates that the wire, normally
rated for dry and wet locations and 75 deg C, is now rated dry/wet up to 90
deg C.
- Peter
Peter T. Parrish, Ph.D., President
California Solar Engineering, Inc.
820 Cynthia Ave., Los Angeles, CA 90065
CA Lic. 854779, NABCEP
Mick,
-2 means 90 degrees C rather than 75. THWN-2 thus means that it is
wet-rated at 90C. That is generally considered Code for arrays,
such as if it is run in NM flex conduit to a traditional module
j-box. The j-box area may be considered to be able to get hot enough
The problem with Al is that, IF there is ever a loose
connection, associated arcing, that it melts not like
copper in the same situation which may arc but not melt.
I have come in on OG jobs where Al was employed and found J
boxes that were [sometimes wet] and had loose connections
and the
Just a minor point: the dash-two appendage brings a wet-rated wire from 75
deg C to 90 deg C.
If you are not in a locale that argues for wet-rated wire and your specific
application does not argue for wet-rated wire, IMHO it is perfectly
acceptable to use THHN wire (90 deg C rated for damp
Peter,
There was a change in the 2008 NEC (I know - CA is just getting to this Code
cycle) that won't allow THHN inside conduit when the conduit is installed in
wet locations, 300.9 (300.5 for underground):
300.9 Raceways in Wet Locations Above Grade.
Where raceways are installed in wet
James – Thank-you! this is a good start and then monitoring the SG after a rest
period w/o loads should help determine the time and SOC.
Off to the lab again Igor, we have tests to run.
Thanks, Dana Orzel
Great Solar Works, Inc
E - d...@solarwork.com
V - 970.626.5253
F -
Darryl,
You are probably aware of this but the Endurance machines are 240
VAC induction machines.
I had asked about their policy on AC coupling their turbines for off
grid use and they were
less than enthusiastic.
You might want to touch base with
Dual rated thhn / thwn complies. And every reel I've ever bought is dual
rated. I've never seen single-rated thhn.
Kirk Herander
Vermont Solar Engineering
802.863.1202
NABCEP(tm) Certified Solar Installer
NYSERDA-eligible Installer
VT Solar Incentive Program Partner
-Original Message-
I've been looking hard to see what manufacturers produce this kinda elusive
#10 THHN/THWN-2 wire.
United Copper Industries (Texas) does. I have a handy spec sheet from them
that I can email anyone who's interested.
marco
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Was Return Amps
Thanks Roy
I usually leap then look,
The customer has it already, I ran it yesterday, on AC couple into the
standalone system, I learned a lot. But it ran, and I am working out some of
the surprises I had. I am building up two inverter boards with the systems to
control
Dana,
Thanks for the input. Excuse me please, OG jobs are?
If the wire had been copper and didn't melt, but instead continued to arc,
would the resultant heat have eventually started a fire?
What type of splice was it?
Does no one else use Al for DC? Here in rocky Vermont/NH,
we use the same
OG - Off Grid
Thanks, Dana Orzel
Great Solar Works, Inc
E - d...@solarwork.com
V - 970.626.5253
F - 970.626.4140
C - 970.209.4076
web - www.solarwork.com
Responsible Technologies for Responsible People since 1988
-Original Message-
From: re-wrenches-boun...@lists.re-wrenches.org
I'm with Dick on this one... Sure, I've seen a few good oopsies involving aluminum, (where the J box does the Salvador Dali thing)... but they're usually installed by "Uncle Larry" types... as long as the install is code compliant (Listed and properly installed), I don't think it maters much.
I cannot speak for what if.
I have seen CU AL bolted in AL mechanical butt splices
where someone did not torque it to spec. and it went to
arcing. Both were a mess ; The butt splice was pitted /
damaged and needed replacement, the AL cable melted and the
copper cable did not.
It the same
check out NEC 110.14Dan BrownFoxfire Energy Corp.Renewable Energy Systems(802)-483-2564www.Foxfire-Energy.comNABCEP #092907-44
Original Message
Subject: [RE-wrenches] AL wire with DC
From: "Dana" d...@solarwork.com
Date: Fri, July 23, 2010 6:54 pm
To: "'RE-wrenches'"
I think some of the advantage of the Cu in a bad connection is that it
dissipates heat better. That might explain the melting Al, but not the Cu.
Cu will melt and cook the insulation if the connection is loose enough at high
enough amperage.
Again, I have not personally seen a problem with Al on
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