Dedicated Circuits Or Up For Local Interpretation?

Mike Finley

I'm confused on dedicated kitchen elec circuits.

• Dishwasher 15amp
• Refrig 15 amp
• Garbage Disposal 15 amp
• Small appliance outlet circuit (1) 20amp GFCI
• Small appliance outlet circuit (2) 20amp GFCI
• Microwave 20 amp
• Range ?amp

I keep seeing back and forth how they have to be dedicated, then I see you can put the dishwasher and the garbage disposal on the same circuit. Officially all dedicated by the NEC or not? Local codes effecting these?

Can a lighting circuit or a low voltage under cabinet lighting transformer branch off of any of the circuits listed?

mdshunk

Any thing that is "built in" (such as a dishwasher or garbage disposal) can't have any other stuff on that circuit if the "buit in" stuff exceeds 50% of the circuit's ampacity. 210.23(A)(2)



(2) Utilization Equipment Fastened in Place.

In the kitchen, pantry,

breakfast room, dining room, or similar area of a dwelling

unit, the two or more 20-ampere small-appliance branch
circuits required by 210.11(C)(1) shall serve all wall and
fl

oor receptacle outlets covered by 210.52(A), all countertop

outlets covered by 210.52(C), and receptacle outlets for

refrigeration equipment.
Exception No. 1: In addition to the required receptacles
specified by 210.52, switched receptacles supplied from a
general-purpose branch circuit as defined in 210.70(A)(1),
Exception No. 1, shall be permitted.
Exception No. 2: The receptacle outlet for refrigeration
equipment shall be permitted to be supplied from an individual
branch circuit rated 15 amperes or greater.
(2) No Other Outlets.

The two or more small-appliance

branch circuits specified in 210.52(B)(1) shall have no

other outlets.
Exception No. 1: A receptacle installed solely for the electrical
supply to and support of an electric clock in any of
the rooms specified in 210.52(B)(1).
Exception No. 2: Receptacles installed to provide power
for supplemental equipment and lighting on gas-fired
ranges, ovens, or counter-mounted cooking units.
(3) Kitchen Receptacle Requirements.

Receptacles installed

in a kitchen to serve countertop surfaces shall be

supplied by not fewer than two small-appliance branch circuits,
either or both of which shall also be permitted to
supply receptacle outlets in the same kitchen and in other
rooms specified in 210.52(B)(1). Additional smallappliance
branch circuits shall be permitted to supply receptacle
outlets in the kitchen and other rooms specified in
210.52(B)(1). No small-appliance branch circuit shall serve
more than one kitchen.

Now, your refrigerator and microwave that you sit on the counter CAN be on those two required small appliance circuits if you want them to be. There is no prohibition against that. If the microwave is built-in (such as a micro-hood), then you refer to the 210.23(A)(2) quoted above and see if it's more than 50% and put it on its own if it is. It is a very good idea (although not code) to give the frige and micro their own circuits.

You can't tap undercabinet lighting off the small appliance circuits because of 210.52(B)(2)

Ranges? Note 4 to table 220.19 says:
4. Branch-Circuit Load. It shall be permissible to calculate the branchcircuit
load for one range in accordance with Table 220.19. The
branch-circuit load for one wall-mounted oven or one countermounted
cooking unit shall be the nameplate rating of the appliance.
The branch-circuit load for a counter-mounted cooking unit and not
more than two wall-mounted ovens, all supplied from a single branch
circuit and located in the same room, shall be calculated by adding the
nameplate rating of the individual appliances and treating this total as
equivalent to one range.

For one range, that table says:
Less than 3-1/3 KW, 80% of nameplate. 3-1/2 to 8-3/4 KW, 80% of nameplate, A range that is up to 12kw shall not be required to have a circuit with a capacity greater than 8KW. For ranges over 12KW but up to 27kw, you add 5% to 8KW for each kilowatt that the range is over 12 kw.

Mike Finley

Great, now I'm more confused then when I started.

thom

I combine the dishwasher and disposal on a single 20A circuit. Separate 20A for the built in microwave. Separate circuit for the refrigerator. Two circuits (max 4 recepts each) for the countertop receptacles.

Teetorbilt

The NEC is great (well sort of), I just use common sense which is always higher than the NEC. All that you have to do is pay attention as to how things are really used.

Case in point; Ol#2 uses a hair roller thingie amps unknown but presumed high. Do we turn it off after the rollers are in? NO! But we fire up the mega watt dryer to speed things up while we are applying makeup in the lighted magnifying mirror and all of the vanity lights are on.

Code is minimal, deal with reality. I probably should run 10GA in there, only have 12 now.

__________________
You can't solve you're problems with the same level of thinking that created the problems.

Albert Einstein

mdshunk

Exactly right, brother.

The NEC minimum wired home will be safe, but it may not suit the way people live and use their home. For instance, I often have 8 to 10 circuits for the kitchen alone. You may also put the receptacles in all the bathrooms on the same circuit. This is fine until you have wife in one bathroom with a hair dryer and daughter in another bathroom with a curling iron. -POP- goes the breaker. Do each bathroom receptacle on its own breaker and have less aggrivation.

Mike Finley

That must be why I keep seeing different versions of this. Some must be based on code and others are recommending based on best practices. Sounds like in a perfect world you would just say put it all on 20 amp independent circuits, but since that's over code and issues such as capacity come into play you get somebody saying put the refrig on a 15 amp one and combine the dishwasher and disposal. In another 5 years the trend will be 2 garbage disposals in a kitchen and it will cause guys to say put the garbage disposals on a sep circuit since the minimally engineered code falls back on percentage of capacity of a circuit.

K2

Most annoying to me is when one gfi runs 3 bathrooms. Another 15 bucks and no extra labor could save years of aggravation and non-gfi extension cords running into bathrooms.

A.W.Davis

When I am doing the electrical for my kitchens I remodel, I usually run 2 new small appliance circuits,new lighting circuit,micro hood/hood circuit,cooktop ignitor circuit...etc etc etc because almost all the houses I have remodeled the kitchen circuits branch off throughout parts of the house,so I just junction the existing circuits and keep them tied together. Then I dont have to worry because I know exactly where my new circuitry goes.

And this is all assuming that there is room in the subpanel ......if not,time to talk to the homeowner for a subpanel upgrade

I agree with Teetor on using common sense on the new circuits.....I always just run new dedicated circuits to major appliances

Brendakeen

It was late, I was tired, and an outlet for an addition faced outside from an existing kitchen wall. I was going to run a hot around a corner from another outlet, but thought it would be easier to run one from the kitchen garbage disposal. Just finished it, the senior EC tapped me on the shoulder and told me I have to fix it on Monday - and gave me the code reference as to why........

Cutting corners (in this case literally), is never a good idea.

Plan 9

I love it when people say "The NEC is minimum, but good sense means exceeding the NEC requirements". This drivel is usually spewed by people unfamiliar with electrical wiring.

I sometimes have builders say this to me, my reply is "Oh Mr. Builder, I see your walls are constructed with 2x4s, wouldn't 4x4s or 2x6s make for a stronger wall?" When a wiseguy tosses out the "NEC minimum" line, you can ask about the depth of his footings or how many layers of floor sheating he's using...

People are always quick to insinuate that your work is not as good as it could be, but they hate it when you apply the same logic to them.

Buyers of electrical services generally seek the lowest bid, then when they sign the contract they suddenly reveal their hidden expectations relating to wire size, etc. This is a very common and very dishonest move.

BTW, the term "Dedicated Circuit" does not appear in the NEC.

Speedy Petey

So you are saying you wire to code and that's it? I agree that the NEC is a safe minimum, and there are lots of folks who exceed it thinking they are doing some great thing. But...there are MANY areas where exceeding it DOES make good sense, and IS necessary. Kitchen circuits are a prime example.
Do you wire only to code minimum all the time?





Neither does the term "neutral", yet we all know exactly what it means and use it every day.
What's your point?

__________________

rabbitgun

Humm................ You may want to open your copy of the NEC to the index. It contains that Neutral word.

mdshunk

I would rephrase that.... "Your buyers of..." We serve different markets. I'm not sure I'd be all that proud of the fact that I do the bare minimum possible for a legal install.

We operate much differently. I get great personal satisfaction from a job well done. You get great personal satisfaction from maximising profits. There is nothing wrong with either motivation. They are just different approaches, with neither one being more right or more wrong. There is a place for both. Being that I am primarily a service electrician, I find it valuable that guys do mimimum NEC installs. It makes more of the so-called "moves, adds, and changes" work for service guys.

RobertCDF

So how do you know that those 2x4 walls are not an "upgrade" from 2x3 walls? Not very common to see 2x3 used, but I bet you could get away with it more times than you think.

As far as I go... Depth of footings always exceeds the local requirents by a few inches at least. As well as diameter of footing. Joists and beams always exceed minimums.

__________________
Robert Shaw
Colorado Springs Custom Decks
Colorado Custom Decks
Custom Composite Decks

Plan 9

I "Charge Large" for custom homes, and I deliver a product commensurate with what I'm charging, extra circuits, special dimmers, the works.

But when the customer wants a low ball price, I deliver a low ball job. This is a common practice for all industries, you can buy a chevy or you can buy a cadillac...

Plan 9

If people can't reset a GFI, they shouldn't be living indoors. Imagine the Neanderthal that notices the receptacle is no longer working and "spends years running extension cords into the bathroom" (I paraphrase).

And it's not $15 extra, it's $3,120 extra. That's 2 Extra GFIs per house, 2 houses per week, 52 weeks a year. When people talk about the cost of things, they forget the fact that we are not planning to retire after we finish this house, we are running a business that runs year round.

Also, a certain percentage of GFIs fail. By installing 3 times as many GFIs as required, you've increased the chances of a failure by triple!!!!! The snappy answer is not always the right one.

Are you a ham?

Speedy Petey

Ok, well it is in there. I was more making a point about the correct term.

In most cases it is referred to as the "grounded neutral".

__________________

Plan 9

The term "Grounded Neutral" does not appear in the NEC.

Mike Finley

Can a nice moderating lurking in the area snip off the posts after #9? The intelligence quotient fell about 60 points on this thread after that.