Circuit Layout Questions

[jeff48356]

Thanks for the replies earlier about the ACFI and smoke alarm question. I have a few more:

1) Regarding the mandatory smoke alarms in the bedrooms, hall, etc, does the circuit that supplies the smoke alarms need to be on its own 15-amp circuit, or can it be tied in with one of the lighting circuits?

2) Do the Refrigerator, Microwave, Disposal, Dishwasher all need to be on each of their own 20-amp circuits?

3) If the house has a dining room, can I wire all the dining room outlets to their own 20-amp circuit, while maintaining two additional circuits for only the kitchen small-appliance outlets?

4) If the microwave oven is over-the-range, can the gas range ignition/clock outlet below it be wired to the same circuit as the microwave?

5) Is it a good idea to wire a pair of 3-way switches to serve the top halves of the living room outlets while keeping the bottom halves always hot?

6) Would you recommend wiring all outdoor outlets to a switch, for the purpose of using Christmas lights?

7) Is it recommended to wire all lighting circuits as 15-amps, keeping them separate from any outlets or anything else besides light fixtures, then wire all outlets as 20-amp circuits no matter where they are located in the house?


Thanks!

 

[raider1]

1) Regarding the mandatory smoke alarms in the bedrooms, hall, etc, does the circuit that supplies the smoke alarms need to be on its own 15-amp circuit, or can it be tied in with one of the lighting circuits?

The NEC doesn't require a dedicated circuit for smoke alarms, they can be installed on one of the lighting circuits.

2) Do the Refrigerator, Microwave, Disposal, Dishwasher all need to be on each of their own 20-amp circuits?

No

3) If the house has a dining room, can I wire all the dining room outlets to their own 20-amp circuit, while maintaining two additional circuits for only the kitchen small-appliance outlets?

You can wire all the dining room receptacle outlets on a separate 20 amp branch circuit, but you must treat this circuit as a small appliance branch circuit and comply with 210.52(B)(2).

4) If the microwave oven is over-the-range, can the gas range ignition/clock outlet below it be wired to the same circuit as the microwave?

No, take a look at 422.19(4)

5) Is it a good idea to wire a pair of 3-way switches to serve the top halves of the living room outlets while keeping the bottom halves always hot?

That decision is best left up to the person paying for the wiring.

6) Would you recommend wiring all outdoor outlets to a switch, for the purpose of using Christmas lights?

No

7) Is it recommended to wire all lighting circuits as 15-amps, keeping them separate from any outlets or anything else besides light fixtures, then wire all outlets as 20-amp circuits no matter where they are located in the house?

Not be me it isn't.

Chris

 

[charlie b]

1. It can be tied to another circuit. But any circuit that includes a bedroom outlet must have AFCI protection (for the whole circuit).

2. They do not have to be. Individual circuits might be something that will make the owner happy (I would want separate circuits myself), but that is not a code requirement.

3. Yes you can. That separate circuit becomes, by definition, an SABC.

4. Not sure, but I think so.

5. I might circuit one LR outlet that way, but not necessarily all of them.

6. I think not. Not all outdoor receptacles. Placing one or two in specific locations, such as under the roof?s overhang, might be a good idea.

7. I would like that for my own house.

 

[charlie b]

4) If the microwave oven is over-the-range, can the gas range ignition/clock outlet below it be wired to the same circuit as the microwave?

No, take a look at 422.19(4)

Typo: It?s 422.16(4). But I think the answer to the question is yes. That article is about range hoods, not the power supply to the range?s ignition and clock.

 

[Dennis Alwon]

Typo: It?s 422.16(4). But I think the answer to the question is yes. That article is about range hoods, not the power supply to the range?s ignition and clock.

We have argued this before but that was when the microwave was part a range hood-- I think they are called range hood microwaves. The arguement was that it wasn't just a range hood so it was exempt.

Regardless I think that article (422.16(4)is a bad one.

 

[raider1]

Typo: It’s 422.16(4). But I think the answer to the question is yes. That article is about range hoods, not the power supply to the range’s ignition and clock.

Sorry, you are correct it is 422.16(B)(4)

A microwave that is designed to be installed above a range and also acts as a range hood is listed as a range hood.

I believe that the reason that this section was added to the 2005 NEC was to address range hood/ microwave units.

Here is a comment from the CMP

________________________________________________________________
17-44 Log #92 NEC-P17 Final Action: Reject
( 422.16(B)(4) (New) )
________________________________________________________________
Submitter: Dan Leaf Rancho Santa Margarita, CA
Comment on Proposal No: 17-21
Recommendation: Delete No. 5 of the Panel Action.
Substantiation: Proposals 17-19 and 17-21 relate only to the wiring method
(cable, conduit, cord, and plug). No substantiation was related to the necessity
for a separate circuit, or the rating of a microwave type hood. 210.23 permits
cord-connected equipment rated up to 50 percent of a multioutlet general
lighting and receptacle circuit. The majority of range hoods do not warrant a
separate circuit, which appears to be a design consideration which may never
be needed. No data was provided to indicate how prevalent replacement with
microwave type hoods is. 90.1(B) indicates Code provisions do not necessarily
provide for future expansion of electrical use, which this provision seems to be.
Panel Meeting Action: Reject
Panel Statement: Due to the likelihood of consumers performing the replacement
of the hood and/or hood-microwave combination, and the large ampere
draw of a microwave oven, the use of an individual branch circuit provides
additional safety measures not otherwise available.
Number Eligible to Vote: 11
Ballot Results: Affirmative: 11

The arguement was that it wasn't just a range hood so it was exempt.

I don't agree, it appears from the ROC that I read that the CMP feels that a microwave/ range hood is covered by 422.16(B)(4).

Chris

 

[Dennis Alwon]

I agree with you, however others don't.

Why is this article only relevant to a cord and plug hood. That is ridiculous. I am not sure I have ever seen a regular range hood with a plug. If this section wants to achieve the goal of design (which the nec says it isn't) then why not say all range hoods should have a separate circuit. Any hood can be changed into a microwave range hood.

BTW, This is the reason I run a separate 20 amp circuit to the hoods.

 

[raider1]

I am not sure I have ever seen a regular range hood with a plug.

I don't believe that I have either.

It appears to me that the CMP went a strange way to require mircrowaves to be on a dedicated circuit. It would be impossible to require a dedicated circuit for a typical portable counter type microwave due to the fact that you don't know where it may be place. But we do know that a microwave/range hood will be cord and plug connected when installed over a range. I have never seen a hardwired microwave/range hood. So knowing this, I feel that this is the reason for the range hood requirement, it is intended to apply to mircowave portion of a microwave/rangehood not to the actual range hood itself.

JMHO,

Chris

 

[Dennis Alwon]

It appears to me that the CMP went a strange way to require mircrowaves to be on a dedicated circuit.
Chris

I agree , esp. since the art puts some tight strings on the type of cord one could use.

Range hoods shall be permitted to be cord-and-plug connected with a flexible cord identified as suitable for use on range hoods in the installation instructions of the appliance manufacturer, where all of the following conditions are met:

Where would you find a cord for a range hood that could meet those specs? Nowhere is my guess.

 

[tallgirl]

I agree with all the code issues mentioned, not that anyone cares.

I do, however, have issue with split receptacle wiring. The switched outlet should always be on the bottom (grounds DOWN!) as the floor or table lap that is attached to that half will seldom be removed. It's the top receptacle that will likely be disconnected and reconnected the most.

 

[charlie b]

The switched outlet should always be on the bottom (grounds DOWN!) as the floor or table lap that is attached to that half will seldom be removed. It's the top receptacle that will likely be disconnected and reconnected the most.

As long as you accept that your statement represents an opinion, a design choice, and not a code requirement, I have no argument against it. But the receptacle can be installed grounds up, and still have the switch control the lower half, and I wouldn't care one way or the other.

 

[480sparky]

I agree with all the code issues mentioned, not that anyone cares.

I do, however, have issue with split receptacle wiring. The switched outlet should always be on the bottom (grounds DOWN!) as the floor or table lap that is attached to that half will seldom be removed. It's the top receptacle that will likely be disconnected and reconnected the most.

I normally wire my receps with grounds down, but I install a split-wired (half-hot) receptacle with the ground up. This identifies it as such quite readily. But this is not any code requirement, just my personal/professional preference.

 

[raider1]

Where would you find a cord for a range hood that could meet those specs? Nowhere is my guess.

If the manufacturer spec's a cord then you must use the cord spec'ed by the manufacturer. Also alot of the microwave/range hoods that I have installed come with a factory installed cord.

Chris

 

[Dennis Alwon]

If the manufacturer spec's a cord then you must use the cord spec'ed by the manufacturer. Also alot of the microwave/range hoods that I have installed come with a factory installed cord.

Chris

Correct-- but standard range hoods don't. My point is you would have a hard time wiring a standard range hood with a cord and plug and meet those criteria.

 

[raider1]

Correct-- but standard range hoods don't. My point is you would have a hard time wiring a standard range hood with a cord and plug and meet those criteria.

Yes, you are correct. I doubt that many standard range hoods are designed and listed for cord and plug connect.

Chris

 

[jerm]

non-interesting tidbit of useless information

non-interesting tidbit of useless information

7) Is it recommended to wire all lighting circuits as 15-amps, keeping them separate from any outlets or anything else besides light fixtures, then wire all outlets as 20-amp circuits no matter where they are located in the house?

Someone else thought this was a good idea too- and thus it became a local amendment to NEC '02 for the City of Tulsa: (It's been a local code for as long as I can remember- back to at least the 80's)

302.2 Receptacles and Light Fixtures(Luminaires). Lights and receptacles shall not be placed on the same circuit in any installation, except that prewired, factory-manufactured portable walls or modular work stations with light and receptacle outlets may be installed on the same circuit. In residences, there shall be no more than nine (9) light fixtures to a circuit. Branch circuit distribution shall be limited to no more than ten (10) receptacle outlets to a circuit.
Exception: Recessed Luminaires (Lighting Fixtures). A circuit supplying recessed luminaire(s) shall be computed based on the maximum volt-ampere rating of the equipment and lamps for which the luminaire(s) is rated.
Exception: In kitchens, utility rooms, and garages there shall be no more than two (2) receptacle outlets to a circuit.

Just in case you decide to wire a house here.


Jeremy
Tulsa, Ok

 

[raider1]

Just in case you decide to wire a house here.

Thanks, but with those kind of local amendments I think I will stay where I am at.

Chris

 

[jerm]

Thanks, but with those kind of local amendments I think I will stay where I am at.

Chris

Thankfully there are only about 10 local amendments to keep up with.

Jeremy
Tulsa, Ok