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Colour coded wires [message #315687] Sat, 08 April 2017 21:06 Go to next message
GMC Jimmy is currently offline  GMC Jimmy   Canada
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Hello All, quick questions regarding the colour of wires.

White and green
White and blue

Which is positive = power and which is negative = ground?

If white is ground are the other colours always positive?

Thanks,
Mike
Re: Colour coded wires [message #315693 is a reply to message #315687] Sat, 08 April 2017 22:08 Go to previous messageGo to next message
midlf is currently offline  midlf   United States
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There are three wiring color systems on GM upfitted coaches. The engine & chassis, the house 12VDC and the house 120VAC. Which one are you talking about.

Engine and chassis generally use black for the negative lead, also known as "ground".

House 12VDC often uses white as negative. But be aware a number of items can have the polarity reversed as those items are mounted on insulating material (wood, fiberglass, fiberboard). Most often on my "74 that is the clearance lights, floor lights and some other lights are suspect.

The 120VAC uses standard electrical code wire colors. White is Neutral. Green is ground. Hot is black or red. The black or red can be deenergized by a switch and thus are not always hot.


Steve Southworth
1974 Glacier TZE064V100150 (for workin on)
1975 Transmode TZE365V100394 (parts & spares)
Palmyra WI
Re: Colour coded wires [message #315705 is a reply to message #315687] Sun, 09 April 2017 03:06 Go to previous messageGo to next message
Ken Burton is currently offline  Ken Burton   United States
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Mike,

Where are you seeing these wires?

I am assuming that you are asking about a white wire with a blue stripe and a white wire with a green stripe.



Ken Burton - N9KB
76 Palm Beach
Hebron, Indiana
Re: Colour coded wires [message #315712 is a reply to message #315687] Sun, 09 April 2017 08:17 Go to previous messageGo to next message
GMC Jimmy is currently offline  GMC Jimmy   Canada
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Thanks fellows, I believe these are 12 volt house wires. The wires I'm referring to are individually coloured, solid white and solid blue as well as solid green. I don't recall seeing any that are solid with a coloured stripe. These wires run along the overhead rails from front to back on both sides as well as through the refrigerator / closet module leading from the main control panel to the rear, water tank, water pump etc.

My coach is a 1975 Coachmen built Royale.

Steve raises a good point for me, I recently installed new 12 volt LED puck lights with the polarity reversed, I think?

The main wires running in my overhead compartments are separate wires, solid white and solid blue, off these wires were smaller gauge wires (black and white) that connect to the lights. When I connected the new lights I connected white to white and black to black (new light fixtures had black and white wires) thinking black was negative and white was positive. When I reconnected the house battery, which was disconnected, and turned on the lights they all worked so I thought I had it correct.

A few other courtesy lights - floor lights I installed had red and black wires on the fixture, here I connected black to black and red to white to the house wiring, they all work.

When I reviewed photos of the water pump taken prior to the renovation I noticed the red wire from the water pump was connected to the solid blue wire and the black wire from the pump was connected to the white wire. I turned the pump switch on and tested the wires and got a 12.8 volt reading using blue as positive and white as negative.

Even though my lights work fine if my lights are wired in reverse is this a problem, can I leave them the way they are or should I reverse all the connections?

Any and all guidance is appreciated,
Regards,
Mike
Re: Colour coded wires [message #315713 is a reply to message #315712] Sun, 09 April 2017 08:48 Go to previous messageGo to next message
midlf is currently offline  midlf   United States
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GMC Jimmy wrote on Sun, 09 April 2017 08:17


Even though my lights work fine if my lights are wired in reverse is this a problem, can I leave them the way they are or should I reverse all the connections?

Any and all guidance is appreciated,
Regards,
Mike


If they work they are connected correctly.

House wiring I described is what is on my '74. Who knows what Coachman did. I'm not sure the Coachman upfitted coach owners know.

With all the various colour standards it is imperative you check with a voltmeter for pos & neg to determine what you have. Besides different upfitter standards you could also have creative wiring by a PO (previous owner). As you indicate you know how to use a voltmeter I don't believe you will have a problem getting things connected correctly. When I get a 12V device of some type the only color code I will trust to indicate polarity is red and black. Then the red is pos and the black is neg.


Steve Southworth
1974 Glacier TZE064V100150 (for workin on)
1975 Transmode TZE365V100394 (parts & spares)
Palmyra WI
Re: [GMCnet] Colour coded wires [message #315732 is a reply to message #315712] Sun, 09 April 2017 11:46 Go to previous messageGo to next message
Ken Henderson is currently offline  Ken Henderson   United States
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Location: Americus, GA
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MIke,

On my X-Birchaven, the original 12VDC house wiring was as you describe:
White for Negative (Ground) and both Blue and Green for Positive. You have
apparently wired most of your fixtures with the sockets Positive and the
center terminals Negative. As long as you're using incandescent, or most
fluorescent bulbs, that will allow the bulbs to work -- they're not
polarity sensitive. But LED bulb ARE polarity sensitive so you'll have to
reverse the wiring. So are the vast majority of devices, like the
refrigerator and furnace with control boards.

There's another potential problem with your arrangement: Most metal
surfaces in a coach are at Ground potential, so if anything conductive
simultaneously contacts exposed metal on the fixture and elsewhere in the
coach, you'll get, at least, sparks. I'd convert ALL the fixtures to
Ground-connected.

Ken H.
Americus, GA
'76 X-Birchaven w/Cad500/Howell EFI & EBL,
Manny Brakes & 1-Ton, etc., etc., etc.
www.gmcwipersetc.com

On Sun, Apr 9, 2017 at 9:17 AM, Mike wrote:

> Thanks fellows, I believe these are 12 volt house wires. The wires I'm
> referring to are individually coloured, solid white and solid blue as well
> as
> solid green. I don't recall seeing any that are solid with a coloured
> stripe. These wires run along the overhead rails from front to back on both
> sides as well as through the refrigerator / closet module leading from the
> main control panel to the rear, water tank, water pump etc.
> ​...
>
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Ken Henderson
Americus, GA
www.gmcwipersetc.com
Large Wiring Diagrams
76 X-Birchaven
76 X-Palm Beach
Re: Colour coded wires [message #315736 is a reply to message #315712] Sun, 09 April 2017 12:24 Go to previous messageGo to next message
Ken Burton is currently offline  Ken Burton   United States
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Registered: January 2004
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Reversed polarity on lights are not just a Coachman issue. On my GM upfitted 1976 Palm Beach the floor lights inside and the clearance lights outside were all wired with the polarity reversed.

Ken Burton - N9KB
76 Palm Beach
Hebron, Indiana
Re: [GMCnet] Colour coded wires [message #315742 is a reply to message #315732] Sun, 09 April 2017 13:25 Go to previous messageGo to next message
<rallymaster is currently offline  <rallymaster   United States
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I've heard that some 12v LED bulbs include a gizmo that makes them work
connected either way.

RonC
------------------
On Sun, 9 Apr 2017 12:46:56 -0400 Ken Henderson
writes:



> As long as you're using incandescent, or
> most
> fluorescent bulbs, that will allow the bulbs to work -- they're not
> polarity sensitive. But LED bulb ARE polarity sensitive so you'll
> have to
> reverse the wiring. So are the vast majority of devices, like the
> refrigerator and furnace with control boards.



Ron & Linda Clark
North Plains, ORYGUN
1978 Eleganza II


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Re: Colour coded wires [message #315745 is a reply to message #315687] Sun, 09 April 2017 15:33 Go to previous messageGo to next message
GMC Jimmy is currently offline  GMC Jimmy   Canada
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Thanks again for the input, I suppose I should do as Ken H. suggests and redo all the connections to the LED lights, just wonder why they all work fine if incorrectly wired? Here is a link to the lights I used if you care to have a look maybe let me know if you see anything that suggests otherwise.

http://www.campingworld.com/shopping/item/led-push-lens-switch-courtesy-light/79915

Regards,
Mike
Re: [GMCnet] Colour coded wires [message #315757 is a reply to message #315745] Sun, 09 April 2017 19:17 Go to previous messageGo to next message
Ken Henderson is currently offline  Ken Henderson   United States
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Mike,

As Ron pointed out, some LED's are wired so they'll work with either
polarity. SInce you ARE using LED's and they're working, you have either
those polarity-neutral LED's (your link doesn't say), or your wiring is
correct.

Ken H.



On Sun, Apr 9, 2017 at 4:33 PM, Mike wrote:

> Thanks again for the input, I suppose I should do as Ken H. suggests and
> redo all the connections to the LED lights, just wonder why they all work
> fine if incorrectly wired? Here is a link to the lights I used if you care
> to have a look maybe let me know if you see anything that suggests
> otherwise.
>
> http://www.campingworld.com/shopping/item/led-push-lens-
> switch-courtesy-light/79915
>
> Regards,
> Mike
>
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> GMCnet mailing list
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Ken Henderson
Americus, GA
www.gmcwipersetc.com
Large Wiring Diagrams
76 X-Birchaven
76 X-Palm Beach
Re: [GMCnet] Colour coded wires [message #315760 is a reply to message #315687] Sun, 09 April 2017 19:41 Go to previous messageGo to next message
Mr ERFisher is currently offline  Mr ERFisher   United States
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On Sat, Apr 8, 2017 at 7:07 PM Mike wrote:

> Hello All, quick questions regarding the colour of wires.



> Don't guess use your free hf voltmeter an measure




> White and green
> White and blue
>
> Which is positive = power and which is negative = ground?
>
> If white is ground are the other colours always positive?
>
> Thanks,
> Mike
>
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
>
--
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“Give a man a fish; you have fed him for today --- give him a URL and
-------
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Re: [GMCnet] Colour coded wires [message #315782 is a reply to message #315757] Mon, 10 April 2017 06:13 Go to previous message
GMC Jimmy is currently offline  GMC Jimmy   Canada
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Ken Henderson wrote on Sun, 09 April 2017 20:17
Mike,

As Ron pointed out, some LED's are wired so they'll work with either
polarity. SInce you ARE using LED's and they're working, you have either
those polarity-neutral LED's (your link doesn't say), or your wiring is
correct.

Ken H.



On Sun, Apr 9, 2017 at 4:33 PM, Mike wrote:

> Thanks again for the input, I suppose I should do as Ken H. suggests and
> redo all the connections to the LED lights, just wonder why they all work
> fine if incorrectly wired? Here is a link to the lights I used if you care
> to have a look maybe let me know if you see anything that suggests
> otherwise.
>
> http://www.campingworld.com/shopping/item/led-push-lens-
> switch-courtesy-light/79915
>
> Regards,
> Mike
>
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
>
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Thanks again for your input Ken and others,
Regards,
Mike
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