Electrical question... UF inside walls?

[Richard]

I've got two 250' unopened rolls of normal "in wall" 12/2 wg. I'm pulling wires across my basement so my brother in law (electrician) can hook them up but, skip the pulling part.

He's out of town right now AND isn't answering his phone

In addition to the above, I have probably another 200' of 12/2 w/g UF wire that is left over from putting some lights outside. The wire has been opened and thrown around a bit but never really abused or kinked.

I KNOW that UF can be a pain in the posterior to work with so let's not even worry about telling me that.

My question is, would'nt I be just as legal if I ran the 12/2 wg UF wire inside my walls instead of the normal 12/2 wg?

If I can do that, I not only get to use up my dead in the water UF wire but might be able to return one or both of my 250' (still wrapped) bundles of 12/2 wg wire and get some cashola back.

Since I can't find my brother in law, I've already pulled two runs across the room, cut the outer sheath off the box/switch ends so the outer sheath goes INTO the box, protruding maybe 2/3 inches inside the box. Then it's black wire, white and copper (black/white are still covered)

I don't really want to put 3 more runs across the room unless I know it's a one way street and I'm done. I don't really want to rip it all out and have to put the 'normal' 12/2 wg in its place.

Logic tells me it MUST be ok to use from a code perspective, just a pain in the hiney to use so only stupid people ask about doing it

 

[CurlyDave]

Ask your BIL first. What makes commons sense in electrical code is not always right.

I just built my own temporary overhead power pole for rebuilding my burned-out house and discovered that I could not use weatherproof wire in the conduit from the weatherhead to the meter and breaker box. It made sense to me to run the weatherproof wire since 18" of it extends out of the weatherhead and is exposed, but the powers that be have prevented this.

I suspect the answer lies in the temperature rating of the wire. The UF is intended for burial, and must be protected from water intrusion in the ground. But, the thermal environment is different than wire behind walls and especially if there is insulation in those walls. The UF will run hotter.

 

[czechsonofagun]

I am afraid, Dave is right. We always think in terms of physical damage to the cable but the heat or what not is another story. With 99.99% chance it will work just fine, but if anything happens - like a fire - the wiring was not up to the code and you are really f@$#illed up.

 

[Richard]

HA! Who would have ever thought about the heat aspect of it!!

What you guys say (unfortunately) makes a great deal of sense. Crapola... I just got done perfecting this first run.

Where are brother in laws when you need em?!!!

I'll freeze in place until this is answered. I'm already not liking my gut feeling.

 

[kenstrac]

N insulation, rated 90 degrees Celsius, 600 volt. Gray PVC jacket. For applications of direct burial, dwellings not exceeding 3 floors above grade, underground feeder to outdoor lighting or apparatus, exposed or concealed wiring in damp, moist, wet, dry, and corrosive locations, general branch circuit wiring and new wiring or replacement wiring. Flame retardant, moisture, fungus, and corrosion resistant. Sunlight resistant jacket. JC-30B Federal specification, ASTM B-3, ASTM B-8 and NY state DOS 16120-880923-2002. U.L. Listed. /2 = 2 insulated wires with bare ground. /3 = 3 insulated wires with bare ground. This Building Wire is one of many top quality items in our Building Wire / Uf department.

Aubuchon Item # 601056

Other Related Departments:
稗uilding Wire / Uf
百outhwire Company Building Wire / Uf
百outhwire Company

This should ansewer your question it's OK

 

[eepete]

Our county follows the NEC. I got dinged when I used UF to run into a light fixture what was outside under a porch. The fixture was one of the ceiling mounted square flush lights, and was rated for outdoor damp location use. The 90 degree rating was the problem. I just used "normal" romex for the entire house from then on out. Only used the UF for outside lighting runs.

So I can't say what all you _can_ use it for, but that experience is at least one thing you _can't_ use it for. You can not run it into a light fixture. I don't know if that applies to a fixture mounted on a box such as a sconce. It _does_ apply to can lights.

Pete

 

[kenstrac]

Our county follows the NEC. I got dinged when I used UF to run into a light fixture what was outside under a porch. The fixture was one of the ceiling mounted square flush lights, and was rated for outdoor damp location use. The 90 degree rating was the problem. I just used "normal" romex for the entire house from then on out. Only used the UF for outside lighting runs.

So I can't say what all you _can_ use it for, but that experience is at least one thing you _can't_ use it for. You can not run it into a light fixture. I don't know if that applies to a fixture mounted on a box such as a sconce. It _does_ apply to can lights.

Pete

If you read my post it says 90 degree C . and you always needed 90C wire to go in a light that was recessed thats why some fixtures had another box on the side so the older wire that was 60c could be used.
If you had used 90C uf wire it would have been APPROVED!

 

[Richard]

As an update... since I have several runs to string around, I've simply started using the open roll of inside 12/2, putting a halt on doing anything with the UF. If I'm not allowed to use it (which is looking like I probably won't be) then I'm still getting work done. If I AM allowed to use it I'll still have other runs to make and can use it there.

Anyone want a screaming deal on some recently untangled 12/2 g UF?


For those of you who are electrically blessed unlike myself... AND who happen to also have a home theater or otherwise nice audio setup...

What are your thoughts on installing what I think is called an isolation transformer near my box, running with 12/3 wire such that each leg is hot with 60 volts instead of one leg using 120. My understanding is this keeps ground loops from happening (really annoying hum in your system for those who have never heard of ground loops) and as I understand it... the isolation transformer would also help "remove" this system from the rest of the (potential of) other household noises.

This (downstairs audio room / mancave) is what I'm working on right now. The rooms electric service is already installed. I'm running a second dedicated circuit around the room so I can keep lights/vacume cleaner and anything else off these outlets. I just had a friend send me an email telling me I should be running 12/3 instead of 12/2 so I could do an isolation transformer (better said, to have one installed for me)

I'll admit I do not understand some of this stuff AND, sheesh.... this is just a simple guy with a simple home system. I'm not Madison Square Gardens!! (although my speakers are VERY sensative and at about 108 db/watt will showcase just about any noise that is present)

 

[tommu56]

For those of you who are electrically blessed unlike myself... AND who happen to also have a home theater or otherwise nice audio setup...

What are your thoughts on installing what I think is called an isolation transformer near my box, running with 12/3 wire such that each leg is hot with 60 volts instead of one leg using 120.

Isolation transformers don't put 60v on each leg that is a misconception it is still 120v to common.
They just isolate the line and load and has inductance to eliminate noise from the line side to load side.

Now for the speakers what type of wire do you has more of an effect on noise spend money on wire here not on the transformer.

I usually use shielded 2 conductor 16 gauge wire ground the shield only at the amp isolate shield at the speaker end and the 2 conductors to the terminals on amp and speakers.


Do put a good belkin or trip light surge suppressor on the equipment.


tom

 

[Richard]

Now for the speakers what type of wire do you has more of an effect on noise spend money on wire here not on the transformer.

I usually use shielded 2 conductor 16 gauge wire ground the shield only at the amp isolate shield at the speaker end and the 2 conductors to the terminals on amp and speakers.


Do put a good belkin or trip light surge suppressor on the equipment.

Thanks Tom.

Right now, I don't really know how my end use will be setup. I'm going to have a dual use system, 2 channel and 5.1 HT. Because of the wife issues, I don't know if I'll have my amps in the front of the room or the rear of the room (she wants rear I want one each, near each front speaker). consequently, I have 2 XLR lines running from "central" to the front three speaker locations (2 per location) I also have some RCA lines going to the same connection in case I don't have my XLR amps up there (Crown K2's). I will also have speaker wire. I've always been of the persuasion that decent speaker wire is decent speaker wire. I've got 2 lines of Carol Cable 12g outdoor low voltage light, wire.

Oh... I biamp each of my front 3 speakers so that's why I've got doubles going to each location.

 

[Inspector507]

Richard, as far as to your question.....UF inside walls?
Yes you can, according to the 2008 NEC. NEC Article 340 covers Type UF cable. Article 340.10(4) reads.......
Installed as nonmetallic-sheathed cable. Where so installed, the installation and conductor requirements shall comply with Parts II and III of Article 334 and shall be of the multiconductor type.

Parts II and III are Installation and Construction Specifications. Both UF and NM cable conductors are required to be 90ｰC rated. However they can only be used at their 60ｰC ampacity. In certain cases where installed in contact with thermal insulation, ampacity adjustments may need to be applied.

 

[eepete]

@kenstrac: Indeed my problem was that the big box store UF was 60 degree C. The cable you had specs for would be fine. My inspector didn't care about the box external to the can lights as far as temperature rating. Don't know if that's right or wrong, but it does say to me that if you can bounce something off the inspector before hand it could avoid a fun discussion about interpreting the code.

@Richard: When I did my theatre, I just made sure all power for everything was on the same phase (side of the 240) and nothing else was on the circuit(s). Some of this comes down to your equipment too. My amps had an RCA connector on them, but it was actually a differential input so hum was not a problem.
I made the mistake of putting the amps close to the speakers. That means I had too much high end role off on the wire going from the preamp/processor to the amp. I should have put the amps close to the preamp/processor and then run whatever it took to get to the speakers. I refuse to get into any discussion about audio wire, but for me I'd be happy with simple 12 gauge wire to the speakers. Bi-amp to the speakers is good. Again for me, the #1 consideration in low level (non speaker wire) is the capacitance of the cable. The 12 gauge romex type wire has low capacitance and at 4 or 8 ohms, the roll off you get will be small compared to the acoustics of the room. Your 12g outdoor low voltage wire will be great.
Finally, if you can put all your equipment in one place and it's on the same circuit or branch, you'll have very few hum problems. That location is the hub of your radial ground system, and this is another good reason to have the amps together and make the speaker wire runs long. The axel of the hub is the preamp or processors, since everything plugs into it. Isolation transformers are for isolation AC circuits and not for providing isolation over the entire audio range at the 60-80 dBV level. Anything in a house with electronics should be plugged into a surge suppressing plug strip.
Subwoofers are different. Because they are low frequency devices, you _can_ run the low level lines to them. It is, however, important that they be on the same circuit (preferable) or same side of the 240. Assumption here is that you have a powered subwoofer. You will also need to play with the position in the room.

Pete

 

[dmccarty]

Richard,

Run some Cat5/6 cable to the receiver location. I put Cat 5 all over our house. But for some daft reasons I did NOT put an outlet near the TV/audio equipment. There are not one but two coax runs to that location but for some reason I did not drop Cat 5. I might have to pull the wire up that wall some day since everything is going digital. We might get away with using wireless but I would rather use Cat 5.

Later,
Dan

 

[eepete]

One could almost start a new thread on home theatre / tv room wiring...

I put 2.5" conduit up to where the TV would be, 1.5" where the speakers would be, and another 2.5" up by where people sit. Don't forget conduit or wires for the rear speakers too. You can order long HDMI cables on the internet for much less than they cost at a electronics box store, and this will fit up the 2.5" conduit. I've had no problems with a 40' HDMI cable. Some of this is influenced by the fact that I hate to look at the equipment. I either want it of to the side (for DVD player), or hidden in the basement (for everything else). Assumption here is that you'd have access to all this on the floor below. By design, I put the area below the TV room as the central area where all the low voltage stuff gets pulled.

If you want to put everything up front, then bring the 2.5" conduit out where you'll hang the TV on the wall, and then at outlet level put an access box. Continue the conduit down into the basement. That still gives you the "floating in space" look for the TV and speakers, but lets you connect up your stuff. As per dmccarty, you'll still want cat5's and RG6's coming up your equipment location.

Yell if you want more ideas, as I'm sure everyone has figured out I'm not shy about typing...

If you can't be right be flexible. And I'm wrong more than I'm right.

Pete

 

[Richard]

Sorry that I abandoned for a while. I'm back

General comments to the above general comments:

1. I've removed all the UF. I couldn't find (see ) the temp rating and had 3 spools of 250' 12-2 w/g so figured I may as well put in what is typical.

Regarding HT wiring... wow...it's a line of wires going across the room.

I have three drops in the front of the room. For each location (left center and right) I have:

2 sets of speaker wire (4 strands) 12g
1 pair of Canare star shield or somethign like that, for a long run of RCA
1 pair (yet to be installed) of Canare or Mogami for 2 XLR jacks
1 pair RG6 cables
1 pair of Cat6 wires

In addition to the above, my center channel location has FOUR runs of Cat6.

Regarding HDMI... I've been told (and started a thread elsewhere that I could find/reference) that HDMI is evolving to where you must be compliant with their requirements or they can prevent you from getting full use of it.

Meaning.... as I've been told, if you go out and buy a Blue Ray DVD, that DVD will have some encryption already built into it that can program your hadware. The hardware on both ends can communicate in each direction with each other and must pass a handshake. Once they do this then all is well. If this handshake fails then you might be stuck at the lowest resolution possible.

Also, I think I understand that HD signals won't be allowed to go over analog wires (component?) after about 12 more months.

Cable length is reported to be an issue on HDMI cables in some areas...and in other areas, cable length does not seem to be a concern. Sort of depends on who you talk to.

I've been told that as this evolves, the HDMI will be doing more and more so the length will become an issue if not already.

My solution? I need about a 45/50' run to go up/down the walls and to traverse the room. Seems you can send HDMI signals over Cat 6 wires for MUCH longer distances.

I'm going to install two HDMI 1.4's if I can find them in 50' length. If that ever quits (or I drive a finish nail through it ) I've got my Cat 6 in there as a backup. Seems it takes TWO runs of Cat 6 to get full use of HDMI so I've got two, double runs to be sure I'll have enough.

For people who are NOT burying their wires in the wall, this clearly isn't an issue. You can always yank the cord & put a new one in. Since I'm burying inside my walls, I am trying to look out as far as I can to get it right upfront.

Regarding conduit.... My firring strips are 2x4's turned sideways so my walls only have 1 1/2" to play with. I also like the idea of adding some conduit but think that is going to limit me to some degree. Anything that has an end on it, might be problematic going through 3/4 or 1" conduit?