I had an inspector fail an install where we pulled a receptacle for the gas cooktop off of the microwave circuit(20amp dedicated). He says the microwave has to be on its own circuit, but most micros only run in the 1100W range. Any opinions?

First off, welcome to ECN!!

Actually, I'd try to state the case in the oposite direction; i.e. the gas cooktop will only pull about 1 amp or so for the light(s) and ignitor.....mention the combination range/microwave and/or microwave/exhaust fan units as possible precedents. Hardly a serious load factor for the microwave circuit.

But sometimes (actually many times) the Code turns a blind eye to reality and you may be stuck rewiring or adding a recept to the general appliance circuit in the kitchen.

Before someone I know quite well, comes on to blast me about the Code remark I must say that the intention of the Code in this case is a very good one. It would be quite easy to overload the gen. purp. circuit with the microwave and just one other appliance.

Usually a polite conversation with the inspector will allow this to pass. But be ready to quote Code references that will help your case.

Good luck.

I don't see how he can require a dedicated circuit for an appliance that drwas less than 50% of circuit ampacity (2400va).
... unless it is juts because he can

Welcome 97_watts

One of the electricians I worked with had a similar situation in a bathroom. He wired a night light (in-wall LED type) downstream from the GFCI. He was failed on this until he could reason with the inspector that there's probably going to be a night light plugged in anyways, and the night light had a rating of 0.1W (which is probably a lot more than it actually pulls). He said the inspector probably passed him because he was nice about it.

Make your point, but be respectful about it.

Electrically speaking, it should be okay as long as the calculated voltage drop is within the specs of the stove, which I'm sure it is (if it's too under voltage, the worst case scenario would be the electronic pilot doesn't light, causing a gas leak if the homeowner doesn't see that it's not lit. This could be one point he makes. remember, I said worst case scenario, as in, say, 1 in a million... blue moon... pigs fly... 3 legged horse won... you get the idea.)

By the way, is it an electrical inspector, or building inspector?

Quote:but most micros only run in the 1100W range.

What is keeping the home owner from putting a huge microwave in there? I know that most don't draw as much as they used to but code is code!

FYI- In Canada, we can put the gas range receptacle on the same circuit as the dining area receptacle. -Sorry, I know that this is the NEC forum, I like to compare all the little differences there is between NEC and CEC.

Code does require a dedicated microwave circuit ...but ONLY if the micro in question as part of an 'over the range and exhaust hood' install. Event there, the requirement is an indirect one ... the dedicated circuit is called for IF the hood is cord & plug connected, only because a micro MIGHT be added later.

It is quite possible that the inspector got confused on this point - dang them code seminars! In general, a micro can be plugged into any receptacle - even the countertop general purpose ones- and I suspect the stove igniter can come off them as well.

Now, as to the igniter tripping the GFI, I simply don't know if that's a concern.

Take a look at 422.16(B)(4)

I will look at that (NEC 2005) on December 8 ... if the state doesn't push it back again

Ryan_J Wrote: Take a look at 422.16(B)(4)

OK I'll bite. How does that apply to the matter at hand? Is this an over range microwave and exhaust hood combination unit?

At the rate things are going, a 2,000 SF or larger home will soon need 400A service just so you can get two 42 breaker panels for all the dedicated circuits.

Either that, or the 42 breaker panel limit imposed on manufacturers needs to be lifted to reflect modern realities.

Joe

422.10(B) allows multiple decidated appliances to share a single branch circuit. 210.23 sets a few restrictions, but a typical 1000W corded microwave and corded gas stove could easily meet these restrictions.

A microwave over the range will probably be listed as an exhaust fan. If it is, and it is cord and plug connected, it requires a dedicated circuit per 422.16(B)(4).

Sorry, I should add that this would not apply to a typical, counter top type of microwave. I didn't see it specified one way or the other in teh original question, and that is why I threw it out there.

[This message has been edited by Ryan_J (edited 11-20-2006).]

But the largest part of the over-the-range microwave load is not the fan, but the microwave. 422.16(B)(3) should apply, and posts no restrictions.

422.16(B)(4) only requires it if the fan is plug-and-cord connected. If the range hood is hardwired, the normal rules would apply.

I must admit, though, I'm stumped as to why a corded range hood would be required to have an individual branch circuit, it doesn't make sense...

Steve, I agree with you. I have a real problem with this requirement; it seems a clear case of the code attempting to 'see into the future'- something the code is NOT intended for.

Moreover, I would consider the hood and igniter to both be incindental to the range ... in much the same way a humidifier might be incidental to a furnace.

There's a reason the NEC ought to stay away from design issues!

Since an over the stove microwave contains an exhaust fan and it is cord connected. It requires a dedicated circuit per 422.16(4), 1-4. (2005)It is being enforced in our area.

Ken

...but if you lop off the NEMA plug and hardwire it, an individual branch circuit isn't required, and you can add other appliances to the string. It just doesn't make sense!

Well, it does kinda make sense in the crystal-ball sort of way- I know in my house, the old hood was hardwired, but I replaced it with a corded microwave without running a new circuit (for shame, I know!). Worked fine until I discovered it shared a single 15A circuit as the kitchen lights, the exterior lights, and both exterior GFCI outlets... So, with a 1000W work light plugged in one outlet and a window AC in the other, popping a bag of popcorn quickly left us in the dark. Needless to say, the microwave is on its own circuit now! Er, well, sharing a 20A with the dishwasher and disposal... Didn't occur to me that it might be a violation. Not like the AHJs look all that hard for things like this.

[This message has been edited by SteveFehr (edited 11-20-2006).]

I agree with the design issue aspect of some new NEC rules. I am starting to think we should just freeze the NEC for a decade or so and let it shake out. There is far too much unnecessary churn in the code community ... but that is what lets those NFPA/IAEI/BOCA et al execs buy a new Mercedes for their girlfriend every year.

Well folks I have to say that from a practical angle, I don't think putting a gas range receptacle on a microwave circuit is a problem, I have to put my inspector hat on for now and say that if an appliance be it cord connected or hard wired is required to be on a separate circuit per the manufacturers installation manual, that's what I enforce. Where do you draw the line? I was personally involved with an installation involving a waste disposal and an under cabinet light. No chance to overload the circuit but the manufacturer spec said separate circuit.
When you are in front of 12 honest men, all the attorney can read is separate circuit.
Keeps me out of court.

Let's just hope the manufacturers of toasters, coffee pots, blenders and hand mixers don't put a recomendation for a separate circuit for their products. We might need a half dozen small appliance circuits.

BTW is this "recomended" or "required" in the instructions? IMHO a "recomendation" has the same force of law as Conagra recomending that you eat your Peter Pan Peanut Butter on Fleishman's bread.
But that brings us to the "classified breaker" mess doesn't it?

Not doing any residential, exhaust fans are cord and plug connected?? Is that for a disconnect?? Where's the outlet?? behind, underneath. What if you use a duplex, can I plug anything else into it?? I've only seen them hardwired