PDA

View Full Version : NM cable and food disposer



dan orourke
11-06-2007, 07:26 PM
.......

Jerry Peck
11-06-2007, 07:28 PM
You can use NM cable, but you would need to protect it from physical damage with flexible metal conduit and an appropriate fitting for it at the dishwasher.

Rick Hurst
11-06-2007, 08:20 PM
Jerry,

For the life of me I can't understand why you can hardwire a disposer like its the same type of an appliance as a water heater. Disposer are going to need to be repaired or replaced more often than a water heater, yet you can't just disconnect a power cord after removal of the unit and be done with it.

Most HO's won't properly connect the wiring to the disposer when replacing one that is hardwired.

I think all appliances should be attached to a cord so that it can be easily disconnected for removal if need be but thats my opinion.

rick

mike huntzinger
11-07-2007, 09:42 AM
Don't forget that the dishwasher is not on a air-gap device

Richard Moore
11-07-2007, 10:43 AM
Deleted

Rick Hurst
11-07-2007, 10:57 AM
Sorry about that Richard. It was a senior moment typing away. I went back and edited my comment. :)

rick

Richard Moore
11-07-2007, 11:07 AM
In that case...I withdraw my "Huh?". :)

So...I'm guessing this wouldn't be right either...;)

Rick Hurst
11-07-2007, 11:29 AM
Now thats exactly what I'm taking about. Great Pic. Richard. Do you mind I use it in my "What Not to Do Picture Book" ?

Richard Moore
11-07-2007, 11:46 AM
Be my guest Rick. Let me know if you want the higher-res original.

BTW, on..."Most HO's won't properly connect the wiring to the disposer when replacing one that is hardwired.

I think all appliances should be attached to a cord so that it can be easily disconnected for removal if need be but thats my opinion."

It's a valid point, but one problem is that disposers don't come with the appliance cord attached. The HO has to buy that and then connect it. I've seen numerous occasions where they manage to screw that up, usually by not using the clamp. I could also argue that armored flex is less subject to damage from the stuff that gets constantly tossed under the kitchen sink and might be preferable because of that.

But, properly installed armored flex, or a properly installed appliance cord and receptacle are both "OK". Unprotected NM, no matter how it is secured and routed...not OK.

Gotta go...I'm just hoping the damn novacaine wears off by the time I get to the inspection. I hate to drool (more than normal) in front of the clients. :D

brian schmitt
11-08-2007, 05:25 PM
i would require a device box in the wall and then flex if romex is used. i too often see flex that just runs into the wall and it gives me pleasure to yank on it and see what comes out of the wall. :D the flex needs to be terminated to the device box with an approved fitting

Jerry Peck
11-08-2007, 08:16 PM
Thanks Jerry. do you happen to know of the code that allow it?

Dan,

From the NEC.
- 110.3 Examination, Identification, Installation, and Use of Equipment.
- - (B) Installation and Use. Listed or labeled equipment shall be installed and used in accordance with any instructions included in the listing or labeling.

I'm guessing that the installation instructions will show it being installed either way - cord and plug *OR* permanently wired.

John Steinke
11-09-2007, 05:27 PM
Hooking up the disposal directly to a tail of NM is fairly common, and the 'trade' has yet to reach a consensus on the issue.

Indeed, the very presence of a disposal is a violation of local ordinances, in some places (like New York City).

If a piece of NM is attached to the disposal, a 'fine point' is that it be attached with a proper fitting, listed for use with NM, that provides both strain relief and abrasion protection.

Using a cord & plug is a matter of some debate. While I personally like it (as there is a local, definite means of disconnect, and the plumber need never open an electrical box) .... various statements by UL can be read to say 'if it was supposed to have a cord, it would have had one put on by the factory.' This view is a frequent cause for debate on the sundry electrical BB's.

If you're going to transition from, say, NM to MC .... well, that brings up the whole issue of a box (for the splice), proper mounting of the MC to the box, etc. If there's MC coming out of the wall, I'd look to see how it was connected ... and WHAT it was connected to! Plastic boxes are generally not listed for connecting MC to them - and boring a hole in the side doesn't change that fact.

Michael Greenwalt
11-10-2007, 09:20 AM
How about..."dang, thats just wrong". Can I put that in my report?

Jerry Peck
11-10-2007, 01:01 PM
How about..."dang, thats just wrong". Can I put that in my report?

Sure, as long as you add an apostrophe ... that's ... ;)

Or say "Dang Bubba, that's just plain ol' wrong." :D

Rick Hurst
11-10-2007, 05:18 PM
Everybody makes fun of "Bubba" till they need their car fixed. ;)

rick

Jerry Peck
11-10-2007, 05:29 PM
Everybody makes fun of "Bubba" till they need their car fixed.

Then Bubba just goes out into his yard and takes the part he needs to fix it off one of those in his front yard.

How cool is that? :D

Dennis Corbett
11-13-2007, 10:14 AM
The installation instructions of the disposal specify the method to connect to power, which will match the listing of the appliance, and rarely permit this type of installation. They usually specifiy a cord connection only. If is states that a permanent wiring connection is allowed, then a disconnect is required to be installed within 50' and within sight of the appliance, and the wiring method must comply with the NEC. A proper connector, protection from damage and support of the cable would all need to be in place.

Jerry Peck
11-13-2007, 02:55 PM
then a disconnect is required to be installed

Or ... a breaker lock out.

I never make that suggestion, hoping that the electrician does not think of it as I do not think much of breaker lock outs (mainly because they are never used - sure, they 'meet minimum' code, but if they are never used 'are they safe'?).

Corey Friedman
11-13-2007, 07:40 PM
Or ... a breaker lock out.

I never make that suggestion, hoping that the electrician does not think of it as I do not think much of breaker lock outs (mainly because they are never used - sure, they 'meet minimum' code, but if they are never used 'are they safe'?).

Hello All,

Warning - thread drift (sort of).

About 12 years ago a friend of mine was killed because the wrong disconnect was locked out on a commercial job.

Corey

Jerry Peck
11-14-2007, 06:26 AM
Corey,

Your post re-enforces (at least to me) that breaker lock-outs are just not safe to rely on. Personally, I wish they had never been allowed.

I cannot think of any reason to save $50 (now, $15 years ago) by using a breaker lock-out instead of a disconnect and risk even one life, in this case, that of your friend.

David Banks
11-14-2007, 07:13 AM
Circuit Breaker Lockout Devices (http://www.bmillerengineering.com/lockout.htm)

Check out Field Lockout incidents below heading.

Jerry Peck
11-14-2007, 02:50 PM
I'm not sure there is a concensus...allowed or not allowed? Or is it "depends on manufacture installation instructions?"

I would say 'allowed unless stated otherwise in the manufacturer's installation instructions' with the caveat that 'allowed' means 'done properly' by protecting the NM cable with an approved raceway which is properly attached and secured to the disposer with a proper fitting and which extends back into the wall and is secured at the wall so it does not pull out.

That last part is the part (and is secured at the wall so it does not pull out.") which is never there even when the NM cable is protected by a raceway.