Shared Circuitry in Kitchen, What is legal and what is not?

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JradSims

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I guess while on the subject of what can share power. This set of drawings shows a receptacle in the laundry room being wired from the Microwave, I don't know the NEC code article that states that that is illegal, however I am pretty sure you cannot use the microwave circuit to feed anything else outside of the kitchen, correct?

If you know the article that would be helpful in writing and RFI, thank you.

Its been a long time since I have done multi family Residential. Any other thoughts and comments would be helpful. As the prints show one of the Kit GFCI small appliance circuit shared with the refrigerator and 2 dining room receptacles. I believe this is legal from what I remember about residential wiring.

I am fairly certain that the dishwasher and disposal can be on the same circuit, and do not need to be 2 separate dedicated 20Amp circuits, as their drawings show?
 
This fails on many levels:
210.11(C)(2) requires the laundry receptacle outlets to have no other outlets. So unless that microwave is in the laundry area, you can't do that.
210.23(A)(2) says fastened in place equipment (assuming built in microwave) cannot exceed 50% of the circuit rating if there are lights or receptacles feeding non-fastened-in-place equipment. Most microwaves would take over half of a 20A circuit.
210.52(B)(2) requires kitchen small appliance circuits to have no other outlets except for the rooms specified in (B)(1) (laundry is not one of the areas).
Somewhere (can't find the section) is a rule requiring a stove vent fan or built-in microwave to be on a dedicated circuit.
Dishwasher and garbage disposal could share a circuit if the sum of the nameplates allow it. If they don't know the nameplates, it is safer to keep them separate.
 
But if the microwave is a fastened in place appliance, and the laundry room receptacle is not the laundry equipment receptacle, but instead supplying some other fastened in place piece of equipment, then the only restriction is that the sum of the loads does not exceed the branch circuit rating. Correct?

Cheers, Wayne
 
wwhitney said:
But if the microwave is a fastened in place appliance, and the laundry room receptacle is not the laundry equipment receptacle, but instead supplying some other fastened in place piece of equipment, then the only restriction is that the sum of the loads does not exceed the branch circuit rating. Correct?

Cheers, Wayne
Click to expand...

The rating of the fastened in place microwave would have to be no more than 50% of the branch circuit rating in order to for that circuit to have other outlets.
 
retirede said:
The rating of the fastened in place microwave would have to be no more than 50% of the branch circuit rating in order to for that circuit to have other outlets.
Click to expand...
Per 210.23(A)(2), that limitation applies only if the branch circuit also supplies "lighting units, cord-and-plug-connected utilization
equipment not fastened in place, or both." Which is why I specified that the other piece of equipment would have to be fastened in place.

Cheers, Wayne
 
wwhitney said:
Per 210.23(A)(2), that limitation applies only if the branch circuit also supplies "lighting units, cord-and-plug-connected utilization
equipment not fastened in place, or both." Which is why I specified that the other piece of equipment would have to be fastened in place.

Cheers, Wayne
Click to expand...

What can a general receptacle outlet do other than serve “cord and plug connected utilization equipment not fastened in place”?

Gotta love code language!
 
I found a section I was thinking of regarding a dedicated circuit for the microwave. I'm thinking of 422.16(B)(4)(3). If you're going to put in a cord connected range hood or microwave/hood combination, that receptacle needs to be an individual branch circuit.
 
JradSims said:
This set of drawings shows a receptacle in the laundry room being wired from the Microwave, I don't know the NEC code article that states that that is illegal, however I am pretty sure you cannot use the microwave circuit to feed anything else outside of the kitchen, correct?
Click to expand...
For one thing you seem to have a designed set of prints that are instructing you on what to do or consider, It is good to question safety or design issues that you may notice whereas the architect or engineer providing the drawing may of overlooked. Which covers your liability if noted within your estimate ( as per drawings ).

Code officials would push their safety agenda as expected .. design is something as well which is a factor in that using the microwave circuit for a Tv on the other side of the wall is perfectly safe as long as its GFI protected outside, the down side is every time someone hits the microwave button you may see disturbance with the image on the Tv being a bad design, is it code compliant chances are no, many people spend hundreds of hours thinking of all the scientific scenarios of an unsafe condition so I'm sure there's a special rule for that one too. Is it dangerous... I cant imagine how.

I once had to trouble shoot a client having their breaker trip when the microwave and AC were running, It ended up the Microwave, the Kitchen CT and the forced air unit all shared the circuit, was it a code violation, who knows , probably, was it dangerous no, the breaker just kept tripping.

The resolve, I just put the FAU on its own circuit and the Microwave on its own circuit. Customer is very happy.
 
Can you really have the refrigerator on one of the small appliance circuits? In the past we would always run a 20 Amp dedicated branch circuit for the refrigerator.
 
JradSims said:
Can you really have the refrigerator on one of the small appliance circuits? In the past we would always run a 20 Amp dedicated branch circuit for the refrigerator.
Click to expand...
Yes the fridge is allowed on the SABC. You can install the fridge outlet on a 15 amp circuit if you wish.

Ron
 
JradSims said:
Can you really have the refrigerator on one of the small appliance circuits? In the past we would always run a 20 Amp dedicated branch circuit for the refrigerator.
Click to expand...
You can do a lot of things that are not the best of ideas. these days refrigerators are not big current draws like they once were.
 
electrofelon said:
A fridge only draws a few amps, I never found a need to put on its own dedicated circuit.
Click to expand...

Define "a few". I see some defrost elements are 725 watts, therefore ~6 amps. Since they do not run with the compressor, still 15 amp circuit works.

I usually put them on a 15 amp dedicated circuit, because then the homeowner can turn off the refrigerator to re-boot the software without dragging the unit out of its resting place to unplug it! My wife can press the simple touch screen buttons and get into a service mode or confused software mode and I have to re-boot it every so often. And it is a "simple" by todays standards, the screen just does temperature, ice style/water and if the night light stays on..... No cameras/WiFi/instant ordering on screen.....
 
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