ECN Forum Forums Code Related Discussion NEC & other Code issues Disconnect for dishwasher?

My problem with the "on/off" switch is it may not disconnect all ungrounded conductors.
If there are servicable componants, like the clock board, that remain powered in the "off" position, this is a hazard.

Greg- that's exactly why this issue came up and UL assurred us that if it's marked "OFF" it disconnects all ungrounded conductors from the appliance (except the ON/OFF switch of course)

Hey Hotline,

Sorry for taking so long to you.

I don't remember seeing any breaker locks on any residential except smoke dectectors (where it is localy required).

Don't see any cords on dishwashers in this area except for a factory one and a bad homeowner job.

We pipe a box in the sink cabinet wall. Then put an extension ring(s) to go thru the wall and back of cabinet. Wip off of the extention. Put what ever garvin is needed on the extension. One reason for this is everything is piped. So the box in the wall can be piped to a few other places. I like it for a home run because it's big and you drop off the dishwasher, disposal, etc. circuit(s) there.

Tom

George and Ryan,

See that is what I mean, if there is a switch that says "OFF", shouldn't that be acceptable? Same goes for T-stat. A Double pole T-stat that says OFF means that both legs of a 220/240 volt heater is disconnected. A T-stat that says "LOW" means that only 1 leg of the feed is disconnected and that should not be accepted. So if a EC install a dishwasher and the cotrol knob says "OFF" then wouldn't it meet the requirements of 422.34?

"but I've yet to see a cord available that meets the requirements of 422.16(B)(2)."

I have, get them at the supply house all the time. A 6' one behind the cabinet and plugged in right next to the garbage disposal. Done-

Now... the switch on the unit as a disconnect for the appliance. Come on now, what if it is the wiring to, or the switch itself that needs to have mainenance on it. Like that big dial on my washer that goes from "off" to "heavy soil".... I have an "Off" and "On" button on my stereo, they don't qualify as a disconnect for anything....My understanding is that the whole general idea is to disconnect for the electrical circuit feeding it, before it is INSIDE the appliance. I guess those same inspectors who accept that, would also accept a disconnect inside an AC unit, or under the skirt of a hot tub? As for 422.34, to verify that it would qualify, would you not need a schematic of every aplliance?



[This message has been edited by e57 (edited 03-04-2006).]

e57- Take a look at 422.34 where it discusses "Unit switches as Disconnecting Means" and you might change your mind.

I just re-read your post and you have read 422.34 Sorry. But I see the ON/OFF requirement as the trigger for being a disconnect.

[This message has been edited by George Little (edited 03-04-2006).]

"disconnects all ungrounded conductors" as a qualifier for this... George I read it, but my question remains, how do you know it qualifies?

Many dishwashers have all controls in the door in a small keypad. Even many older ones have a series of buttons also on the door. Most of those are low voltage controls, which means that they are powered by a transformer that is still on when you hit the "off" button. Either way there would still be a hazardous voltage present in the junction box of the unit, and in close proximity of the series of relays and solinoids below the unit.

I imagine someone reaching below, bumping the door, and starting the unit while changing a belt...

We are at the mercy of the U/L listing. I suppose that may be valid with new appliances but they were a lot looser with "ON/OFF" in the past. That is particularly true in electronics that are never really off unless they are unplugged.
These days they mark that switch "power" or the global friendly "0/1".