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re: "Is the workbench powered using a male-male extension cord to the wall?"
I was hoping nobody would ask that question!
The workbench is a rather old structure (1950's?) that came with the house. It is basically framed with full-sized 2 x 4's (doubled up for the legs) and topped with 2 x 8's, upon which I added 1/4" hardboard to get a smooth yet replaceable work surface. The unit is just over 8' long and about 3' deep. It's a rather hefty unit.
It is more or less "permanently" wired into the shop. There is a junction box attached to a back leg of the workbench with a run of 12/2 NM from a junction box in the ceiling. From the workbench junction box I ran more 12/2 along the frame and attached the outlets in surface mount boxes.
I assume the junction box attached to the workbench is probably not code, but based on the weight of the workbench and it's location, it's not something that ever gets moved. If it needed to be moved, I would disconnect the wires in the ceiling box so no live wires would be exposed.
What would be required to bring this up to code? Would a male-male be required? Would just a male pig-tail from the junction box to a receptacle be better? Or is it OK as is?
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That's correct. Neither is the NM cable going to it.

That's mostly safe. But it's still not Code-compliant.

There are at least two ways to bring it up to code.
Method 1: a) Bolt the workbench to the floor so it becomes "permanently installed". b) Keep the workbench junction box where it is, and run individual conductors or NM cable inside some type of rigid conduit[*]. AFAIK, all flexible conduit is prohibited by Code from being used "where subject to physical damage"; so is type MC (metal clad) cable. I think this use probably qualifies as "subject to physical damage". Armored cable isn't approved here either, because Code requires that it "closely follow" the building surface (IOW, you're not permitted to install armored cable loose in the air).
Method 2: a) Install a receptable in the ceiling junction box. b) Replace the NM cable with Type SJ (or similar) cable -- this is the stuff that's used for equipment power cords -- and put a grounded plug on the end of it. Make sure to get 12ga cable with three conductors (black, white, and green).
[*] It is a common misconception that the Code prohibits use of NM inside conduit. This is not true; in fact, the Code explicitly _requires_ the use of conduit to protect NM from physical damage where necessary [2008 NEC, Article 334.15(B)]. What's not allowed is to run NM in *flexible* conduit.

Male-to-male extension cords are highly unsafe, and *never* compliant with any codes.

Yes. See Method 2 above.

No, it's not. It's mostly safe. But it definitely does not comply with Code.
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On 6/2/2010 11:34 AM, Doug Miller wrote:

You would think more inspectors would be aware of this, but I've found it necessary to point out this very issue on a couple of occasions to our newer local inspectors ... where the old timers will get you is that you do have to de-rate the ampacity of the circuit in your calculations due to heat buildup when doing so.
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On Jun 2, 12:34 pm, snipped-for-privacy@milmac.com (Doug Miller) wrote:

Thanks Doug.
One minor point (question?)
You said "IOW, you're not permitted to install armored cable loose in the air. "
No where is there any cable "loose in the air". The cable from the ceiling box is stapled to boards that is TapCon-ed to the block wall in the corner of the shop and behind a cabinet. The NM cable is secured within inches of both junction boxes, as well as along it's run along the boards.
Things would have to go horribly wrong in the shop for the run from the ceiling junction box to the workbench junction box to be damaged. And I mean just about total devastation.
All in all, I've always felt the installation was as you noted: "It's mostly safe. But it definitely does not comply with Code".
The use of Type SJ (or similar) cable to a receptacle would be a simple fix - other than the fact that I need to empty and move the cabinet to gain access to the area. There's no telling what's lurking in the bowels of that cabinet. ;-)
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[...]

Okay, that changes things a bit. I had pictured a free-standing bench. Not so? Your bench is right up against a wall?
If that's the case, then armored cable is definitely OK, and if you can persuade your local inspector that the location is not "subject to physical damage" then exposed NM, MC, or individual conductors in any type of flexible conduit will be too.

*That* may be a Code violation (junction boxes are required to be accessible).
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On Jun 2, 1:58 pm, snipped-for-privacy@milmac.com (Doug Miller) wrote:

Yes. Small shop, workbench is in a corner, therefore against *two* walls. The "open end" has the junction box attached to the upper portion of the back leg. The space between the workbench and the other side wall is filled with a free standing metal cabinet.

What the code definition of "accessible"? Can it be behind a free standing cabinet? Or a dryer? Or a couch?
Does it have to be in plain sight so you can walk right up and touch it?
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[...]

Heck, in that case, you probably meet code with the existing cable if you just secure the bench to the wall(s) and/or the floor -- anything that makes the bench actually attached to the structure of the building. [...]

"Capable of being removed or exposed without damaging the building structure or finish or not permanently closed in by the structure or finish of the building." [2008 NEC, Article 100]

Not if the cabinet is permanently installed. OK if the cabinet can be moved out of the way without damaging anything.

Yes to both.

No. The master bath in my house has a junction box concealed behind a large mirror -- but the mirror is in a channel that permits sliding it aside. That box is "accessible".
The Code has another term, "readily accessible", which is much more restrictive. The gist of it is that if in order to get to something you have to move anything out of the way, or fetch a ladder or a stool, then it isn't "readily accessible". Breaker panels, fuse boxes, service disconnects, etc. are required to be "readily accessible". Junction boxes need only be "accessible".
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On Jun 2, 5:18 pm, snipped-for-privacy@milmac.com (Doug Miller) wrote:

I'll slap some Velcro on the back of the workbench and call it attached. :-)
Thanks for the info.
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On 6/2/2010 3:19 PM, DerbyDad03 wrote:

Remember the purpose of the code--it's not to pass judgment on your furniture arrangement, it's to make sure that the building is safely wired. If it met code when it was newly constructed, it still meets code after you've moved in no matter where you put the furniture and appliances. In general though, it's best to make sure that the inspector can get at anything that he needs to inspect, not because a piece of furniture in front of it will fail code, but because if the inspector has to wait for you to move furniture so he can get at something he needs to see he may just say to Hell with it and reschedule the inspection.
But, with regard to all matters code, YMMV. Codes are generally a matter of local law and they can be very bizarre.
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snipped-for-privacy@milmac.com (Doug Miller) writes:

This is often used when placing outlets on concrete/cinderblock walls; the NM runs along the joist, and enters conduit at the sill plate and the conduit runs vertically down the wall. A plastic bushing should be used where the NM enters the conduit to prevent abrasion, even better would be a handy box with appropriate fittings (setscrew or compression connector for the conduit, and NM clamp for the NM), although with the handy box in place, I'd just run THHN to from the handy box to the outlet.
The caveat here is to ensure that the fill ratio isn't exceeded.
One 12-2/wg NM in 1/2 emt is ok. two, probably not.
scott
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male-male is *illegal* in a lot of jurisdictions. Serious risk if the upstream (i.e. the wall outlet fed from utility power) end is plugged in and the other end is -not-.
In most jurisdictions the outlets on the bench is perfectly legal (no different than a convenience outlet on a stove, say), with a simple drop cord to plug it into a wall outlet. I would probably consider using greenlee armored cable and a twist-lok connector. <grin>
I'd use greenlee, or actual EMT conduit, for all the 'on bench' inter- connections. something -could- fly around and hit bare wiring (even NM) I don't believe in giving MURPHY a -chance- to muck with things. :)
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Bill wrote:

The last is just silly...
I'd (more or less) agree w/ the other posters...
Agree on separating the 120V on own circuits and moving up to 30A/10ga over 20A/12ga for at least a couple of the circuits (and if do any, might as well do all).
Slight disagreement w/ at least one suggestion...30A @240V is enough for any reasonably efficient 5-horse single-phase motor and given that going to >30A outlets raises compatibility and cost significantly, I don't see any need/justification for more than that for anything other than a dedicated welder circuit or somesuch. Presuming, of course, that the distances are reasonable so that voltage drops are 5% or less and this is a typical home shop, not commercial or a behemoth thing...
Agree that the "never enough" for 120V and the overhead are certainly also truisms as well as the admonition for lights to not be on work outlets.
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Never combine two motor loads on one circuit. The simultaneous starting current will typically take out the breaker when you least want it to.
Two motors on any breaker / circuit is a big no-no and will also not protect your equipment from any locked-rotor current. This is when the equipment jams or shorts out and the circuit breaker is sized wrong for that piece of equipment (big enough to carry the two motors), does not trip and your motor windings go up in smoke. Bigger repair bill and possible fire hazard.
Proper motor protection circuits found in industry typically have two levels of protection, one for the large starting current and one for the typical loaded running current. Anything lasting longer than the two situations, at that current level, will trip out the breaker / circuit interupter.
In home usage only one level of current protection is typically afforded with a simple breaker. Don't defeat it by combining two motor devices. The Electrical Inspector would advise against you doing this, if he catches it or you ask.
is enough for any reasonably efficient 5-horse single-phase motor and given that going to >30A outlets raises compatibility and cost significantly, I don't see any need/justification for more than that for anything other than a dedicated welder circuit or somesuch. Presuming, of course, that the distances are reasonable so that voltage drops are 5% or less and this is a typical home shop, not commercial or a behemoth thing...
Agree that the "never enough" for 120V and the overhead are certainly also truisms as well as the admonition for lights to not be on work outlets.
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snipped-for-privacy@www.giganews.uk.> wrote:

Nonsense.
Only if you turn both of them on at the same moment -- a rather rare occurrence in a one-man home workshop, I'd say.

More nonsense.

You have a serious misunderstanding of the purpose of overcurrent protective devices. Circuit breakers are there to protect the branch circuit wiring, *not* the loads that are plugged into the receptacles on that circuit. If a particular load needs some specific level of overcurrent protection, that is achieved by fusing that load.

We're talking about a one-man home workshop here, not an industrial installation.

One-man home workshop, remember? How often will two tools be operated simultaneously?

Nonsense. How often do you turn two motors on at the same time? How often do you *use* two motors at the same time (unless one of them is the dust collector)?
There is _absolutely nothing wrong_ with the OP putting his table saw and air compressor on the same circuit, or his drill press and jointer. They will *never* be in use at the same time -- and even if they are, it's not likely to be a problem unless they're switched on simultaneously. Now you tell me how often that's going to happen. One-man home workshop, remember?
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Doug Miller wrote:

...
What he said... :)
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From your nonsense comments I see you must operate your compressor with a manual on/off switch. Imagine you recommending a person operating a table saw to have it stall in the middle of a cut because they forgot to turn off the air compressor. You give dangerous advice here.
I don't now what you kind of air compressor you operate but real compressors have a pressure sensor on the tank to keep the pressure within a range set by the operator.
As far as overcurrent protection, you have no idea. Don't even try to convince me of anything in that regard.
I was trying to display some common sense and adherance to most electrical safety codes. You could try reading yours.
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snipped-for-privacy@www.giganews.uk.> wrote:

OK, I'll give you that one. The rest of your post was complete nonsense.

Point out exactly what errors you imagine I made in that regard. Hint: you are completely clueless if you think that branch circuit overcurrent protection has anything to do with protecting the loads that are plugged into that circuit.

Had you actually managed to do so, it would have been its initial appearance in your posts.

I'm quite familiar with mine; much more so, apparently, than you are with yours or any others. Here's a link to mine; perhaps you'd be good enough to point out where it prohibits putting two motors on the same circuit.
http://nfpaweb3.gvpi.net/rrserver/browser?title=/NFPASTD/7008SB
Perhaps you'd also be good enough to explain why the US NEC requires only two small-appliance circuits in a kitchen -- which, according to you, is enough for only two motors. Gosh, I must be in big trouble: blender, two mixers, coffee grinder, can opener... all that on only two circuits...
Don't presume to lecture me on residential electrical installations. You have no idea.

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On 6/1/2010 5:05 PM, Doug Miller wrote:

Ayup ...

Ayup ...

Ayup!!
BTW, you're getting mellow in your old age, Doug! :)
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[...]
Thanks, Swing, I've been working on that actually...
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On 6/1/2010 5:41 PM, Doug Miller wrote:

Me too ... but age based cynicism creeps into everything, if you let it.
How's your Eagle Scout doing these days? Strangely enough, it is the thought of folks like your son, and Leon's, that give us old cynics hope for the future.
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