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Well, it's really 4, 4 and 4. I thought the 120 quad above the 220v for the TS could share, and the other quad would run from a circuit dedicated to it. Having the two duplex halves of a quad running off of totally separate circuits seems downright dangerous (because its confusing)!

I could run my two 120v branch circuits from one 12-3 cable and a tandem breaker. Is there much advantage to two cables and two breakers?
As a non-professional, I suspect the price structure favors one 250' spool of cable. Others have suggested 12-3 (partially, for the unforeseeable future, I think), in addition to the fact that you get two 120v branch circuits from one cable). I intended to install only 20 Amp circuits everywhere--however Joseph brought up some new issues concerning this to my attention. My TS wants to be on a 20 Amp circuilt. I understand 12 gauge wire is suitable for that (10 being required only on 30 Amp circuits, from my understanding).
I need to assimilate some of this. I'll keep thinking!
It might be helpful to discuss concerns relating to putting lighting on 20 Amp circuits, as I think there is some inconsistency present. One advantage I see is that you can occasionally demand a little more from one of the circuits. I already have a separate lighting fixture/circuit, from the main panel, so a total loss of lighting is only a possibility with a total power outtage.
Bill
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*snip*

*snip*
If you're running 2 120V circuits from a 12-3 cable, consider that the neutral would have to carry twice as much current as it would in most situations.
Two single breakers gives you the capability to move or replace just one, should the need arise.
Puckdropper
--
Never teach your apprentice everything you know.

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"Puckdropper" <puckdropper(at)yahoo(dot)com> wrote in message

So, if I understand you correctly, 12-3 cable isn't really intended for running two 120v circuits, despite the fact that it's possible to do so. I did not understand this.
Looks like I can get a 250 ft roll of Romex 12-2 for about $70 or so. I'll be careful to avoid "burn-thru" (I searched for at least 15 minutes last night until I figured out what mytical quality being "burn-thru resistent" referred to). No need to explain, I already know!!! : )
Lew, Swingman, Mike, What do you think, 12-2 all around (you could talk me into some 10-2)? All 20 Amp circuits. Will inspectors like it?
Bill
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wrote:

(This is not true. See my other post.)

Yes, it is. He's mistaken.
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<puckdropper(at)yahoo(dot)com> wrote:

No, it doesn't, unless it's installed improperly. Properly installed (with the two hot conductors on opposite legs of the service), the current in the neutral conductor is the *difference* of the currents in the two hots, not their sum. For example, with 11 amps on one leg, and 7 amps on the other, the current in the neutral is 4 amps, not 18.
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snipped-for-privacy@milmac.com (Doug Miller) wrote in Puckdropper

Bill, I'm sorry for the incorrect information. After much thought, I think I can explain why Doug's right. (On opposite legs, the current draws are going two different directions (on a plot). That's why they subtract and not add.)
Doug, thanks for the correction.
Puckdropper
--
Never teach your apprentice everything you know.

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<puckdropper(at)yahoo(dot)com> wrote:

graceful as you at having the misconception corrected.
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"Puckdropper" <puckdropper(at)yahoo(dot)com> wrote in message Puckdropper

Hey, no problem, thank you for offering your help! This 'lectricy is interesting stuff, huh?
After much thought, I

That is a helpful explanation. Thank you!
Bill

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Actually, the currents are added. The effect is subtraction.
One leg has a -1 vector tagged to it so when adding it becomes subtraction.
Remember in the US and many other places the two voltages are 180 degrees out of phase with the other.
Martin
Martin H. Eastburn @ home at Lions' Lair with our computer lionslair at consolidated dot net "Our Republic and the Press will Rise or Fall Together": Joseph Pulitzer TSRA: Endowed; NRA LOH & Patron Member, Golden Eagle, Patriot's Medal. NRA Second Amendment Task Force Charter Charter Founder IHMSA and NRA Metallic Silhouette maker & member. http://lufkinced.com /
On 6/9/2010 8:38 AM, Puckdropper wrote:

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Or 120 degrees out of phase if fed off a network three phase system. Ths can be common in apartment buildings or large residental blocks. Now you get the vector sum of two loads and have to consider the power factor also.
The end result is a low current, in the neutral, anyway, unless you have pf correction on one and not the other. Not likely in a residence.
Actually, the currents are added. The effect is subtraction.
One leg has a -1 vector tagged to it so when adding it becomes subtraction.
Remember in the US and many other places the two voltages are 180 degrees out of phase with the other.
Martin
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The phase angle determines what you get.
Anyway - most 3-phase apartment house services are in fact 180 split windings. e.g. delta with centers of the delta sides are grounded. You don't get multiple phases for normal home use.
Martin
Martin H. Eastburn @ home at Lions' Lair with our computer lionslair at consolidated dot net "Our Republic and the Press will Rise or Fall Together": Joseph Pulitzer TSRA: Endowed; NRA LOH & Patron Member, Golden Eagle, Patriot's Medal. NRA Second Amendment Task Force Charter Charter Founder IHMSA and NRA Metallic Silhouette maker & member. http://lufkinced.com /
On 6/9/2010 11:27 PM, Josepi wrote:

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That would depend where your located. This 120 degree system is quite common in some areas.
The voltages aimed at are 125 / 216 vac so that the 120v loads get a little high voltage and the 240 loads get a slightly low voltage, all within legal acceptable standards.
The energy metering takes a full two element Whr meter instead of a 1.5 element meter used for regular 120/240 vac. Costs a bit more so it it typically only used in high rises and other large residential blocks.
In apartment or condo blocks, usually each floor will be fed off two out of three phases, in the construction I have been involved with. One neutral conductor and three phase conductors can feed the whole building up the electrical service shaft. This can save some copper and use one big 3ph 4W transformer for the building. 6 phase star can be used in a similar method but power theft is easier to accomplish by customers and it takes more copper.
With a delta configuration only **one** centre tapped phase can be grounded. This was called 3 ph 4 wire delta and the metering was too complicated for many EE people and abandoned. This was common with a 120/240 vac residential service where the customer wanted to run a small 3 phase meat slicer or saw. A second transformer could be added at 60 degrees for open delta, quite economically and get three phase and single phase.

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"Martin H. Eastburn" wrote:

HUH?
Residential construction in the USA is provided with the following:
Either 120/240, 3 wire Edison from a single phase utility x'fmr
or
240V, 3 phase, 3 wire with one leg center tapped and grounded.
This is known as "Wild leg delta".
If you grab the wrong leg, you get 167V (Remember vector addition?) to ground.
Heard more than a few "war" stories about wild leg delta.
At one time was used by the small RECs as a means of reducing the amount of equipment req'd, but fortunately is being replaced, but you still might find some in the boonies.
The 3rd configuration found in light commercial such as shopping centers and some apartment complexes is 208Y/120/3PH/4Wire.
You get 208V leg to leg, 120V any leg to ground.
Utility x'fmr is 3 PH.
You need to be careful to select equipment rated for 208V, not 240V, or you will need a buck-boost x'fmr.
Lew
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wrote:

Right, that's not a good idea.

It depends mostly on the locations of the recepticals -- if you can run one continuous cable from the breaker panel to the first one to the last one, it may make more sense to use 12-3. If you have to split it in two different directions, use two separate runs of 12-2.

No, it doesn't. You "suspect". But apparently you haven't actually checked. Prices this morning at Lowes.com show $118 for 250' of 12-3 and $70 for 250' of 12-2.
Plus, 12ga wire is inappropriate for about half of your wiring job. It's unnecessary for your lighting circuit(s) -- those can use 14ga easily. And you _really should not_ use 12ga wire for your 240V circuits. I assure you, you will come to regret that decision. I *strongly* recommend using 10ga _at minimum_ on the circuits for your table saw and air compressor.

That's really not as big an advantage as it seems. Especially when you can run 168 feet of 12-2 for the same price as 100 feet of 12-3.

That's correct... but what if you decide to buy a larger, more powerful table saw at some time in the future? I cannot emphasize this too strongly: don't make decisions now that will constrain your decisions in the future. Run 10ga wire to your 240V outlets.

What does that mean? Lighting is pretty much a fixed load. A 15-amp circuit is sufficient to power 1440 watts of lighting. That's thirty-six 48" fluorescent tubes. There's _no reason_ to use 12ga wire for a lighting circuit.
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Doug, Thank you for your thoughtful and detailed reply! I printed it ut. -Bill
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On 6/7/10 11:17 PM, Bill wrote:

I see these all the time and have built many. I also hear that phrase all the time... it may be a regional thing.
All you're talking about is a homemade extension cord with 4 outlets. Couldn't you just buy a power strip with a long cord? Those thing are already UL listed and many of them have a built-in GFCI on the plug.
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It's no different than any extension cord. Use type SJ 12-3 with ground and a 4" deep box; make sure you use the appropriate fitting to hold the SJ to the box. If you use a metal box, make sure you ground the box.
scott
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Typically in residential wiring cables the ground wire is not included in the conductor count. If you bought other type cable, for almost any other application, the total number of conductors would be included in the count. So yes, 12/3 NMD, NMW, would include a black, red, white plus a bare conductor. If you bought a 12/3 cable in cab tire (the black rubber type flexible stuff) it would include a black, white and green, or three other colours depending on the application it was desigend for and the company making it.
For ground wiring, I like to keep them as continuous as possible. I would probably bring my incoming ground wire, very long from the cable, wrap it around the box screw and then to each receptical in turn with one long, uncut run, all from the cable. In lieu of that, to the box screw, then to a wire nut (connector / Marrette) with two pigtails... one to each receptical ground. If the wire is stranded you may want to crimp a lug on the end, depending on how well the connector is made for that style of conductor.
I am not sure what the point of the four banger receptical would be. I have installed this config in walls a few times and it is a mistake for most applications. Most wall wart AC adapters cover too many recepticals, the six banger receptical splitters cover the other two recepticals and you only get use of two of the wired in ones, the current capacity is still only 15 amps between the four and that limits what you can accidentally use at one time and a few other reasons I can't think of right now. They do work well for light draw test equipment (say electronics).
The number 12 wire may be a good idea if the extension cord has some length to elimate voltage drop and be easier on higher powered equipment (saws, routers etc..) but then you probably wouldn't want to share a bunch of equipment like that on that quad box. Individual circuits are still the best bet for when your grandson comes in and cuts that piece of wood or blows off his dirty pants while you are jointing that piece of briar you just bought.
If you O/C protect the 12/3 cable with a 20 amp circuit then you need 20 amp recepticals (have a T slot in the neutral side) and you are over fusing any portable power tools you use. You may lose some of the human protection afforded by the recommended max circuit capacity for the equipment.
In short, if you are going to open up your walls, spend the time and money to put a few outlets around the room on individual circuits. Possibly one on the ceiling for who-knows-what later. You don't have to use them. I wired mine with one receptical per breaker..kept them high for over workbenches. Any 240v circuits will have to be crawling through the attic or kept close to the breaker panel or piped across the ceiling after.
BTW: There are defined standards for every current and voltage rating of receptical so they can't be used in the wrong application. It is a good idea to stick to these standards. I believe I have found charts on GE or Hubbel websites with pics to identify each type.
Personally, If I were you, I would pay for a wiring inspection. You run all your cables to the boxes and call them to come and then again after the recepticals are installed and closed up. I would run the wire, install the boxes and wire the recepticals and leave hanging for the rough in inspection. (the wall finisher will not like the receptical wired in bu they can be turned sideways and pushed through the holes before mounting the drywall etc... Inform the inspector you are not too sure and have a close look, He will advise some requirements, some tips, and some hints of how to make it right or better, usually. After the first wave of inspection, hook up your breakers in the panel. If nervous about that get some help, friend, passing electrician etc... With inspection, you'll feel better, your home insurance will feel better after a fire, and you just bought yourself some protection against insurance, weasel out.
Josephi - You read my mind. A pair of duplex outlets was what I had in mind by "quad in a box". I honestly did not intend to be vague.
I had a question concerning the ground wires in wiring a quad box in a branch circuit (both outlets to be run in series from the same hot). Resources I have found have been vague. My understanding includes that a wire attached to the ground terminal of the first duplex outlet would be pigtailed with the upstream ground wire and a wire which is screwed to the box, and that the wire attached to the ground terminal of the second duplex outlet would be pigtailed with the downstream ground wire and a wire which is screwed to the (metal) box. So the box would contain exactly 2 connectors and two wires would be screwed to the box, possibly at the same place. Does this seem like the best way to you? I can think of equivalent configurations, but this one seems good. Another possibility seems to be to use a 3rd pigtail connecting the first two pigtail connections and connect them to the box that way instead. Which way seems preferable to you?
BTW, using 12-3 cable for my run, every wire I mentioned connecting in the paragraph above would be bare (right?).
Thank you! Bill
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I recently read somewhere, perhaps in the NEC, about a requirement of submission of desogn drawings (prepared by somoneone who knows how to) that are not less than 30" etc. Is this part of the wiring inspection process? You are talking about working through the city/municipality right? The insurance issue is one I have been concerned about. I am a little afraid to let an inspector see what I "inherited" when I bought my house (although the house inspector didn't note any problems in this area). Someone with a trained eye wouldn't have trouble finding existing things to object to... BTW, my project includes the installation of a subpanel adjacent to the main panel.
Bill
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What do you mean by "and closed up"?
Most of the application for a "(Garage) Building Building" permit consists of "Maps, Sketches, and Other Exhibits: Applicant must attach appropriate sufficient maps, sketches, and other exhibits, including a signed Homeowners Association Affirmation of Notification.
I have 2 questions:
1) Are before and after SU documents, along with written summaries likely to suffice for this? 2) Is my Homeowners Association likely to raise their head (for fear of all the the outlets)? --Maybe I'll layout a SU document with buffers, fans, and other quiet amenities. : )
3) I can see why some people might not go this route. It surely gets in the way of changing your mind. It sounds sort of silly, but "how much "vaguness" is allowed? Is a phrase such as "add fluorescent lighting to the ceiling" unacceptable?
The application fee for the building permit the maximum of .05/sq^2 or $25. Is that likely to cover both the "rough-in" and "final inspection", or are their typically further fees?
Bill
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