dishwasher wiring

[Dennis Alwon]

Not many (maybe even none) dishwashers have a "unit switch" AFAIK.

Most anymore have electronic controls and no true mechanical control switches. Simpler and typically older units with a mechanical time switch may have qualified though.

My question is why not? and can you tell from the diagram if that is a unit switch. Not sure what #5 goes to

 

[kwired]

My question is why not? and can you tell from the diagram if that is a unit switch. Not sure what #5 goes to

Fair enough.

Likely that switch in the diagram would qualify as a "unit switch" it interrupts all ungrounded supply conductors. I myself still have some thoughts that it should be close as practical to where the incoming supply conductors enter the appliance, but NEC doesn't really mention anything about that, and that is seldom how it would work with a dishwasher. Switch would typically be on upper front of door, leaving you with energized conductor routed through the appliance to the termination box at bottom of the appliance, still creates some potential hazard for a repair man vs something at or before that termination box.

As far as #5 goes, doesn't matter, it is not energized anytime the switch is open anyway.

 

[Dennis Alwon]

Fair enough.

Likely that switch in the diagram would qualify as a "unit switch" it interrupts all ungrounded supply conductors. I myself still have some thoughts that it should be close as practical to where the incoming supply conductors enter the appliance, but NEC doesn't really mention anything about that, and that is seldom how it would work with a dishwasher. Switch would typically be on upper front of door, leaving you with energized conductor routed through the appliance to the termination box at bottom of the appliance, still creates some potential hazard for a repair man vs something at or before that termination box.

As far as #5 goes, doesn't matter, it is not energized anytime the switch is open anyway.

TY

I have heard for years that the unit switch does not shut the line off but every diagram I have looked at- just a few- seems to show that it does. I don't know where or why that thought came about or why the unit switch would not shut the power off entirely. We have been going on the assumption that it worked a certain way but never checked.

I wonder whether the industry changed on this issue.

 

[sparkync]

Dennis, just going over the different answers again. If I put a receptacle under the sink for a plug for a dishwasher, the outlet will still have to be a GFCI because it's within 6 ft. of the sink, right?
Thanks

 

[kwired]

Dennis, just going over the different answers again. If I put a receptacle under the sink for a plug for a dishwasher, the outlet will still have to be a GFCI because it's within 6 ft. of the sink, right?
Thanks

2017 NEC wording:


2020 is same or very similar, 2014 did not have this wording and some places would make you put GFCI there, though the DW did require GFCI protection anyway, but I assume you are asking because of earlier mentioning that NC doesn't require DW to have GFCI protection.

 

[jap]

Sometimes its best to install a GFI breaker in the panel and get the Ground Fault protection out of the way right off the bat.

Then you can use a switch as control or for a disconnecting means if you want to down stream of that.

JAP>

 

[Dennis Alwon]

2017 NEC wording:
View attachment 2559484

2020 is same or very similar, 2014 did not have this wording and some places would make you put GFCI there, though the DW did require GFCI protection anyway, but I assume you are asking because of earlier mentioning that NC doesn't require DW to have GFCI protection.

I think your answer is here. Now did they intend to include receptacles under the sink in a kitchen, IDK but I think they did. I believe in NC there is no exception on this... If so, it become moot on dishwasher with a cord and plug setup

(6) Kitchens — where the receptacles are installed to serve
the countertop surfaces
(7) Sinks — where receptacles are installed within 1.8 m
(6 ft) from the top inside edge of the bowl of the sink

 

[tthh]

Just put a cord on it. I just installed a new Bosch dishwasher where I'm at and it came with a cord kit that plugs into some proprietary receptacle on the dishwasher. I suspect they are all going this way. GFCI under the sink or in the panel your choice.

 

[LarryFine]

As a side note, I have never installed a cord on a dishwasher or a disposer; every one has been hard-wired.

 

[tthh]

As a side note, I have never installed a cord on a dishwasher or a disposer; every one has been hard-wired.

I never did before either. The rental house I'm in right now has both of those corded.

 

[Dennis Alwon]

As a side note, I have never installed a cord on a dishwasher or a disposer; every one has been hard-wired.

Most of the higher end ones we do today all come with cords and ready to plug in.

 

[wwhitney]

FWIW, with the Bosch, there's a kit available if you want to hardwire it. The kit just consists of a junction box with a cord pigtail that has their special receptacle on the end to plug onto the dishwasher. Which raises the question of whether you could just take the supplied cord and cut off the NEMA 5-15 plug and hardwire it yourself.

Cheers, Wayne

 

[Hv&Lv]

Dennis, just going over the different answers again. If I put a receptacle under the sink for a plug for a dishwasher, the outlet will still have to be a GFCI because it's within 6 ft. of the sink, right?
Thanks

From 2017 210.8:

For the purposes of this section, when determining distance
from receptacles the distance shall be measured as the shortest path the cord of an appliance connected to the receptacle would follow without piercing a floor, wall, ceiling, or fixed barrier, or passing through a door, doorway, or window.

I would say no, measuring through the cabinet door counts here and would exclude it.

 

[kwired]

I think your answer is here. Now did they intend to include receptacles under the sink in a kitchen, IDK but I think they did. I believe in NC there is no exception on this... If so, it become moot on dishwasher with a cord and plug setup

similar questions before they added the clarification in 2017 has been the topic of discussion on this site about whether or not a receptacle say in a bedroom but also within six feet of the bathroom sink needs GFCI protection. Before 2017 it basically was up to AHJ as to whether or not they will allow it, now code says it is allowed. Under the kitchen sink or even outlet in an upper cabinet near the kitchen sink does not require GFCI, unless some other code section would call for it - like if the receptacle is for the dishwasher. I believe you have mentioned before NC exempted the GFCI for DW's requirement, so I see no reason to require GFCI for that receptacle from a code enforcement perspective.

 

[kwired]

FWIW, with the Bosch, there's a kit available if you want to hardwire it. The kit just consists of a junction box with a cord pigtail that has their special receptacle on the end to plug onto the dishwasher. Which raises the question of whether you could just take the supplied cord and cut off the NEMA 5-15 plug and hardwire it yourself.

Cheers, Wayne

Ever residential grade DW I ever seen, besides "portable units" just has a termination box with a 1/2 KO for you to connect either a cord or some other Ch 3 wiring method.

 

[kwired]

As a side note, I have never installed a cord on a dishwasher or a disposer; every one has been hard-wired.

Is that just what is common in your area? Maybe even local amendments requiring that?

NEC has for long time allowed those to be cord and plug connected.

A problem I had more recent years was a DW that didn't have sink base or even other cabinet adjacent that is open type to place a receptacle in. No problem I can hard wire it and place a lock device on breaker. Unfortunately it was a BR panel and their single pole BR lock attachment does not fit AFCI/GFCI or DF breakers (at the time anyway)

 

[Dennis Alwon]

Ever residential grade DW I ever seen, besides "portable units" just has a termination box with a 1/2 KO for you to connect either a cord or some other Ch 3 wiring method.

I believe the cheaper dishwasher units do not have the cord. All the bosch and other high end brands have cord and plug. That is what we have seen around here but we do high end homes so that may be the difference.

 

[Dennis Alwon]

similar questions before they added the clarification in 2017 has been the topic of discussion on this site about whether or not a receptacle say in a bedroom but also within six feet of the bathroom sink needs GFCI protection. Before 2017 it basically was up to AHJ as to whether or not they will allow it, now code says it is allowed. Under the kitchen sink or even outlet in an upper cabinet near the kitchen sink does not require GFCI, unless some other code section would call for it - like if the receptacle is for the dishwasher. I believe you have mentioned before NC exempted the GFCI for DW's requirement, so I see no reason to require GFCI for that receptacle from a code enforcement perspective.

I disagree. Notice that the took the word "door" in the 2020

For the purposes of this section, when determining the distance from receptacles the distance shall be measured as the shortest path the supply cord of an appliance connected to the receptacle would follow without piercing a floor, wall, ceiling, or fixed barrier, or the shortest path without passing through a window.

 

[Dennis Alwon]

Dennis, just going over the different answers again. If I put a receptacle under the sink for a plug for a dishwasher, the outlet will still have to be a GFCI because it's within 6 ft. of the sink, right?
Thanks

I sent an email to Joe Starling to get his take but since we are on the 2017 I don't believe we need gfci. I was thinking 2020 but we are not there with the residential part in NC.

 

[kwired]

Is that just what is common in your area? Maybe even local amendments requiring that?

NEC has for long time allowed those to be cord and plug connected.

I disagree. Notice that the took the word "door" in the 2020

But now they maybe need to define "window"?? Open front cabinet maybe has a "window" instead of a door on it? Some call an opening in a wall with no glass or no door a window or even "pass through window".

We might not be done with changes here.