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williamp 06-04-2007 03:32 PM

Switch Wiring
I have a problem that seems simple but local electricians are quoting me $200 and up to do a simple light wiring connection.

In the ceiling is an octagon box with a power feed coming from another room. This box feeds power to a group of high hat lights. There also is a feed from the box to a single light switch on the wall.
An electrician installed a seperate group of high hats without any power feed. He added a feed wire from the last light to the light switch box for the 1st group of lights. His intention before he walked off the job was to connect power to the new group by connecting the 2 switches in the switch box. He mentioned 'piggybacking' the power feed.
My question is how do I connect the 2 switches so that each switch will power each group of lights independently without having to pay hundreds?


KUIPORNG 06-04-2007 03:41 PM

If all pre-wire is done correctly... not difficult... and do you have a opened framed structure or everything is drywalled?

anyway... I assume everything is drywalled... then you need to sort out what wires are what and hopped that they were done correctly...

if they were done incorrectly or missing somthing... it will be difficult and if it is already drywalled... it will be tripple more difficult....

anyway... it is always more difficult to follow up someone else job rather than doing from scatch...

I think your issue is no really "$200 for making a switch" rather than "if the electrician has left you with somthing in good shape"...

JohnJ0906 06-04-2007 03:42 PM

Need some more info. EXACTLY what wires you have, where they run, and the number of insulated conductors in each. (Don't count the bare wire)

williamp 06-04-2007 03:54 PM

The room is open framed, no drywall has gone up yet so it is very easy to follow the wiring. All the new wiring has been run and looks good, it is set-ip identical to the first group.

The wires are basic 14 ga. Romex, - black hot, white neutral and ground.

The original group of lights is currently connected and working perfectly. The new ones(only 3) are the ones not connected yet.
Is it even possible to piggyback from one switch to another?

KUIPORNG 06-04-2007 04:01 PM

then I would say it is not difficult for you to figure out... but still is going to be a harrsel... as it is always a headache to figure out which is which... when there are so many wires here or there.... but you kind of need to start labelling all wires in questions and start to use method of elimination to sort out what is what.... there are a few ways to wire things for the same purposes... you probably need a multi-meter and some spare wires for connecting the expose connection to the multi-meter to figure things out... as I assume your circuits is not alive...

williamp 06-05-2007 10:43 PM

Please help
I am begging for help on this one!!!
Is it possible to piggyback power from one light switch to another. Someone suggested splicing the incoming wire with pigtails to each of the switches.
Or is it better just to re-wire and run a new switch feed directly to the ceiling box and copy the wiring pattern that is being used for the existing group of high hats?
Any thoughts would be appreciated.

pjpjpjpj 06-06-2007 12:33 AM

2 Attachment(s)
williamp, from your description, it does not sound like there is a way to get the two separate light circuits on two separate switches within that switch box, using the wiring already installed. If there is only one line from the existing (working) lights to the switch box, this line will have hot, but will not have neutral; the other wire is the "return" (I'm sure there is an official name for it, I just call it that), meaning that, when the switch is on, it is effectively a continuation of the hot line. See the first attached sketch I drew below (just trace the path of flow along the hot wire and you will see that there is no neutral available in the switch box). Does this look about right? Black is black, blue is your white wires (sorry, my drawing program does not let me draw in white). The black and white wires may be switched in your house, but are the connections about the same arrangement?

If what I sketched is correct - as far as there only being one cable from the attic box to the existing switch, and then another stubbed-in cable from the other set of lights, then your only option is to get power from the existing attic box. The easiest way would be to add another attic box in the line from the second set of lights. See my second attached sketch below. It would require you to rewire within the first attic box a little bit as well. Make sure you follow all code requirements, etc., etc.

(You can click on the thumbnails to enlarge).

Now, if there are actually two lines running from the existing light circuit down to the switch box (and the cable from the other lights is a third), that is a different story.

Good luck - let us know what comes of it. :thumbsup:

williamp 06-06-2007 11:16 PM

pj, your response is much appreciated. I don't know what the electrician was thinking when he wired the way that he did. Your model looks solid, the way it should be done correctly. I am going to give your diagram a try this weekend and will let you know what happened.


HouseHelper 06-07-2007 08:17 AM

One comment on PJs diagrams: In a switch loop, when using NM cable, the feed to a switch should be on the white wire (remarked with tape or marker to signify hot) and the switched hot returning to the fixture should be the black wire. Always.

pjpjpjpj 06-07-2007 12:04 PM

Thanks, HH - my house is not consistently wired this way (I don't know if the contractor didn't bother or if the previous owners reinstalled switches and didn't pay attention), so I did not know if there was a proper way to do it. But other than the wire colors, I believe the diagram is correct.

williamp 06-14-2007 04:47 PM

The wiring diagram you provided worked great and saved alot of money and stress. I also added HH's advise about the black wire being the return feed from the switch.
I finally found out what the contractor's intentions were. He was going to 'pigtail' the constant power feed going into the switch box and bring power to both switches that way. Supposedly it meets code in this part of the country. Is pigtailing switches something that is common in the electrical field?
One follow up question I had is about the ground(bare copper) wires. When there is more that 1 ground wire in a ceiling box, is it safe to connect together and cap them? These ground wires are from the new wires I brought to the box. It looks like the original contractor cut the ground wires for the incoming power feed and the original switch so that they were not sticking out from under the overall jacket. Can I leave this as is or does every wire always need to be grounded?

jwhite 06-14-2007 07:40 PM

with very few exceptions for isolated grounds (which you may never run into) ALL GROUNDS IN EVERY BOX MUST BE CONNECTED TOGETHER.

They must be connected to the recepticle, and metal parts of the light fixture, and frames of equpment, and any other metal part that could even if some off chance, under the worst case, become energized.

If some previous HACK cut off the ground wire so that it is too short, then you MUST pull new cable with a proper ground wire.

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