[RE-wrenches] double insulated wire

Sun Jun 30 06:48:23 PDT 2013

We have standardized on DC markings White negative and Red positive.

Chris Mason
Comet Systems
Anguilla (264) 235-5670
St. Kitts  (869) 662-5670
skype netconcepts

NABCEP Certified Solar PV Installer™
Renewable Energy Systems professional
Generac Generators Factory technician
On Jun 29, 2013 8:30 PM, "David Katz" <dkatz at aeesolar.com> wrote:

> Watch out for accountants who become installers.  They always thing red
> negative and black positive.
> David Katz
>
> Sent from my iPhone
>
> On Jun 28, 2013, at 5:40 PM, "Ray Walters" <ray at solarray.com> wrote:
>
> > Richard, when you use your Fluke 87  to measure Vdc, black is negative,
> > red is positive.  The black is labeled common because the meter can also
> > be used for current measurements. (I have a Fluke 89)
> > When you start using black wire for positive, it may be allowed by code,
> > but there just isn't a good reason for it.
> > Its just too easy to make a mistake, and its just too easy to adhere to
> > the multimeter convention and keep it safer.
> >
> > I have personally watched seasoned electricians argue color coding with
> > me, then minutes later get mixed up and wire two 10 module strings in
> > series, because they forgot for a moment that they were working on a
> > positive grounded system.  The result was an almost 1000 v arc that
> > jumped an opened fuse holder (only rated to 600 vdc) and started a small
> > fire in the inverter, before I disconnected it at the array.
> >
> > Please give one example where leaving positive unmarked with black wire
> > makes more sense than taping it.  Colored electrical tape, and label
> > tape are much cheaper than inverters and people.  THHN, USE, and PV wire
> > can all be purchased in red, white, and black. (which saves time with
> > multiple  home runs)
> > Its not code yet, but it's good sense, all the way back to the color
> > coded jumper cables you might have in your trunk.
> > I have discussed this with many electricians over the years, but
> > eventually every single one sees that's its really easy, no cost, and
> > still code compliant to make things safer.
> >
> > R.Ray Walters
> > CTO, Solarray, Inc
> > Nabcep Certified PV Installer,
> > Licensed Master Electrician
> > Solar Design Engineer
> > 303 505-8760
> >
> > On 6/28/2013 2:49 PM, Richard L Ratico wrote:
> >> Respectfully:
> >> My Fluke 87 does not use this convention. Black is labeled the COMMON
> terminal,
> >> the red terminal is labeled according to function, not polarity.
> Battery based
> >> inverter manus. using this convention typically provide BOS enclosures
> with OCP
> >> for only one inverter conductor. This requires the other conductor to be
> >> grounded and colored white or gray. Therefore IMHO the manus. should
> use only +
> >> or - to identify inverter terminals. Many, if not most, battery
> companies do
> >> this already. Mr. Wiles is, of course, welcome to his opinion.
> >>
> >> I would suggest we stay with the NEC required use of any color other
> than white,
> >> green or gray for ungrounded conductors. This gives installers some
> flexibility.
> >> It also encourages the guy on the hot roof or the gal in the stuffy
> mechanical
> >> room to check and double check, maybe triple check polarity, as they
> should be
> >> doing anyway. I do like the practice of enhanced identification of
> conductors in
> >> positive ground systems.
> >>
> >> Dick Ratico
> >> Solarwind Electric
> >>
> >>
> >> --- You wrote:
> >> The convention of red for positive and black for negative is not just
> >> automotive.  It is also used by all battery based inverter manus, all
> >> battery companies, and all multimeters.
> >> John Wiles also agrees;
> >> red = positive, black = negative  for ungrounded systems
> >> red = positive, white = negative for negative grounded systems
> >> white = positive, black = negative for pos grounded systems.
> >> I take it a step further, and use white label tape with red lettering
> >> that says "+ positive ground + ",
> >> because I've seen so many problems with positive grounded systems, and
> >> people not getting polarity correct.
> >> All of this is NEC compliant, and follows standard conventions.
> >> Make it easy on yourself and your journeymen on a hot roof, and have
> >> your color coding match their multimeter.
> >> You might save an inverter or even a life.
> >>
> >> R.Ray Walters
> >> CTO, Solarray, Inc
> >> Nabcep Certified PV Installer,
> >> Licensed Master Electrician
> >> Solar Design Engineer
> >> 303 505-8760
> >>
> >> On 6/28/2013 12:09 PM, Allan Sindelar wrote:
> >>> On 6/28/2013 11:47 AM, aram at aramsolar.com wrote:
> >>>> And of course Red for positive and black for negative.
> >>>> Most building departments have not pick up on this yet. But they will.
> >>>> Aram
> >>> Where does "of course Red for positive and black for negative" come
> >>> from, please? I only know it as an automotive standard that has often
> >>> caused confusion when used by DIY offgridders in years past, as black
> >>> thus could represent either positive or negative in a DC conductor
> pair.
> >>> Is there yet a convention for ungrounded arrays? While red and black
> >>> are technically correct as ungrounded current-carrying conductors, use
> >>> of this color convention could cause as much confusion as resolve it
> >>> in the future. How about "black and black" or for that matter "yellow
> >>> and orange" (if supplied by manufacturers) for ungrounded arrays?
> >>> Thanks, Allan
> >>>
> >>> *Allan Sindelar*
> >>> _Allan at positiveenergysolar.com_ <mailto:Allan at positiveenergysolar.com>
> >>> NABCEP Certified PV Installation Professional
> >>> NABCEP Certified Technical Sales Professional
> >>> New Mexico EE98J Journeyman Electrician
> >>> Founder and Chief Technology Officer
> >>> *Positive Energy, Inc.*, a Certified B Corporation^TM
> >>> 3209 Richards Lane
> >>> Santa Fe, New Mexico 87507
> >>> *505 424-1112 office 780-2738 cell*
> >>> _www.positiveenergysolar.com_ <http://www.positiveenergysolar.com/>
> >> --- end of quote ---
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