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A.D. Miller
02-25-2009, 12:37 PM
Is a built-in microwave oven allowed to be installed in a kitchen island cabinet on the GFCI receptacle circuit?:confused:

Jerry Peck
02-25-2009, 01:21 PM
Can't think of why not.

Just make sure that it is not a built-in and using that one and only receptacle supplied for that island.

Scott Patterson
02-25-2009, 01:24 PM
I see them fairly often like that. Like Jerry, I can't see anything wrong with it.

A.D. Miller
02-25-2009, 01:24 PM
Can't think of why not.

Just make sure that it is not a built-in and using that one and only receptacle supplied for that island.

JP: Thanks.

H.G. Watson, Sr.
02-25-2009, 02:07 PM
Is a built-in microwave oven allowed to be installed ina kitchen island cabinet on the GFCI receptacle circuit?:confused:


From what I understand of the original post, if you are referring to the required Small Appliance circuits for that kitchen, I respectfully disagree.

Installed built-in to cabinet microwave supplied by one of the two required 20 amp Small Appliance circuits serving the counter top area, there could be a problem.

If it is not a built-in only unit or permanently installed/attached convertable unit then it may be powered by the one of the two required 20 amp SA circuits that are required for countertops, etc. as long as it is just "resting" on a countertop or shelf or slid onto supporting brackets. Once the device/appliance is attached/installed/mounted to or especially within cabinetry it becomes utilization equipment fixed in place or connected to ventillation there can be an issue, as those circuits are restricted as to their purpose, especially if the means to disconnect is concealed and the receptacle is not located in the manner perscribed and is accessible as per the specifications for the those two minimally required small appliance circuits which serve countertop receptacles.

If in order to move/remove the unit would require the use of a tool, removal of a fastener, or to disconnect the unit (unplug the cap) would require the unit to be moved or removed from its installed fixed-in-place state in order to view its nameplate and rating, then it wouldn't be allowed to "share" either small appliance circuit irrespective of its rating.

Jerry Peck
02-25-2009, 02:48 PM
Installed built-in to cabinet microwave supplied by one of the two required 20 amp Small Appliance circuits serving the counter top area, there would be a problem.

That receptacle would be allowed on either of the required two (or more) 20 amp small appliance circuits, as those circuits are 'not only for' receptacles which serve the countertop spaces, however, as I said above, that would not be allowed to count as the required receptacle for the island.

A similar example would be an appliance in an appliance garage on the countertop, the receptacle in the appliance garage is allowed on either of the minimum two (or more) 20 amp small appliance circuits, it is just not allowed to be counted as a receptacle serving the countertop spaces.

ken horak
02-25-2009, 03:17 PM
Another thing to keep in mind is NEC 210.23 (A) (1) & (A) (2)

If the microwave is on a branch circuit with more then 1 outlet:

(A) (1) - Cord and plug connected equipment not fastened in place can not exceed 80% of the branch circuit rating

(A) (2) - Utilization equipment fastened in place Shall not exceed 50% of the branch circuit rating

Makes a big difference if the unit is fastened in place or not.

Fred Warner
02-25-2009, 05:07 PM
I'm not clear on whether the microwave has a cord and plug or whether it is wired in directly on the same circuit with the island GFCI?

H.G. Watson, Sr.
02-25-2009, 05:47 PM
If you are installing a micro-hood (exaust hood) in over-the island cabinets it, like a range hood would require a dedicated branch-circuit.


If you are installing below in the island base cabinets (or above but not a micro-hood and the receptacle is within 20 inches of the island countertop), and the nameplate & rating are viewable without de-installing the fixted-in-place utilization equipment (such as nameplate being viewable when you open the door vs. on the back side of the appliance) and its rating is less than or equal to half of the circuit's rating, and the unit can be unplugged without de-installing OR you have an alternate means of disconnect (indicating switch) for the receptacle serving the appliance, it may be permitted to share the circuit.

Fred Warner
02-25-2009, 06:05 PM
What I'm trying to get to is this: If it's a cord-and-plug connected small appliance, then it's like any other appliance that would be simply plugged into a nearby small appliance receptacle.
If it's hard-wired, it is not permitted to share the SABC.

Jerry Peck
02-25-2009, 06:51 PM
The original poster (Aaron) did state:

installed in a kitchen island cabinet

Thus it is, to our knowledge, "installed in a kitchen island cabinet" and not "over it" as in a microwave range hood.

And that it was on:

on the GFCI receptacle circuit?

I, and others, made the presumption that it is cord and plug connected, and, being built-in, it is likely that Aaron would not have been able to tell, unless the cord and plug extended through the side of the cabinet space it was in and plugged into a receptacle in an adjoining cabinet ... or maybe even below it.

H.G. Watson, Sr.
02-25-2009, 07:31 PM
What I'm trying to get to is this: If it's a cord-and-plug connected small appliance, then it's like any other appliance that would be simply plugged into a nearby small appliance receptacle.
If it's hard-wired, it is not permitted to share the SABC.

Fred Warner,

If "installed" it becomes fixed in place utilization equipment. It is an Appliance. That "fixed-in-place" status is not bearing on if its electrical connection is via cord-and-plug. Examples: a disposer that is cord-and-plug-connected electrically is still "fixed-in-place" when it is mounted on the sink and connected to the plumbing system; just as a wall oven mounted in a cabinet is "fixed in place" even when using a cord-set to electrically connect it.

It may not exceed 50% of the circuit's rating and still be on a shared circuit.



210.23 Permissible Loads. In no case shall the load exceed the branch-circuit ampere rating. An individual branch circuit shall be permitted to supply any load for which it is rated. A branch circuit supplying two or more outlets or receptacles shall supply only the loads specified according to its size as specified in 210.23(A) through (D) and as summarized in 210.24 and Table 210.24

(A) 15- and 20-Ampere Branch Circuits. A 15- or 20-ampere branch circuit shall be permitted to supply lighting units or other utilization equipment, or a combination of both and shall comply with 210.23(A)(1) and (A)(2).

Exception: The small-appliance branch circuits, laundry branch circuits, and bathroom branch circuits required in a dwelling unit(s) by 210.11(C)(1), (C)(2), and (C)(3) shall supply only the receptacle outlets specified in that section.

(1) Cord-and-Plug-Connected Equipment Not Fastened in Place. The rating of any one cord-and-plug-connected utilization equipment not fastened in place shall not exceed 80 percent of the branch-circuit ampere rating.

(2) Utilization Equipment Fastened in Place. The total rating of utilization equipment fastened in place, other than luminaires, shall not exceed 50 percent of the branch-circuit ampere rating where lighting units, cord-and-plug-connected utilization equuipment not fastened in place, or both, are also supplied."

If fixed-in-place "installed" appliance on this circuit its name plate rating must be visible or easily accessible while said appliance remains fixed in place [422.60(B)].

If fixed-in-place its cap must be able to be disconnected without the use of special tools or removing fasteners OR must be able to be disconnected to service and/or maintain the fixed-in-place, "installed" microwave by another means, such as a rated indicating (marked off) switched receptacle within sight and control of the appliance, for example. The cord/plug set is not listed or allowed to be "run through" a cabinet wall to a receptacle in another location, it must be in the same "space" as the appliance, it is not listed for other than that purpose and because microwave is not a gas-fueled cooking appliance nor is it a clock. [210.52(B)].

A.D. Miller
02-26-2009, 07:06 AM
The original poster (Aaron) did state:


Thus it is, to our knowledge, "installed in a kitchen island cabinet" and not "over it" as in a microwave range hood.

And that it was on:


I, and others, made the presumption that it is cord and plug connected, and, being built-in, it is likely that Aaron would not have been able to tell, unless the cord and plug extended through the side of the cabinet space it was in and plugged into a receptacle in an adjoining cabinet ... or maybe even below it.

JP and others: Sorry, I did not specify. This was a drawer-type micorwave that was not cord and plug connected, but hard wired. It was built into the island base cabinet.

Fred Warner
02-26-2009, 07:54 AM
Is a built-in microwave oven allowed to be installed in a kitchen island cabinet on the GFCI receptacle circuit?:confused:

My answer to this question as presented is NO. 210.52(C)(2) establishes the requirement for at least one receptacle to be installed on the island, but 210.52 establishes that 210.52(C)(2) is in addition to a receptacle located within cabinets or cupboards (210.52(3). This means that a receptacle located on an island to satisfy 210.52(C)(2) cannot satisfy 210.52(3). :)

Jerry Peck
02-26-2009, 08:04 AM
My answer to this question as presented is NO. 210.52(C)(2) establishes the requirement for at least one receptacle to be installed on the island, but 210.52 establishes that 210.52(C)(2) is in addition to a receptacle located within cabinets or cupboards (210.52(3). This means that a receptacle located on an island to satisfy 210.52(C)(2) cannot satisfy 210.52(3). :)

Fred,

However, that receptacle, if present, is not intended to satisfy 210.52(C)(2) but to be 'in addition to', which is allowed. :)

However, as the installation has been revised from being cord and plug connected to being permanently-wired, and is on the two small appliance circuits, what say you?

Aaron,

Were you able to see that it was not cord and plug connected?

You stated that this was a drawer type microwave, indicating that it slides in and out(?), in which case permanent wiring would need to allow for that flexibility, or, are you meaning it - as a unit - replaced a 'drawer' and was fixed in place with no sliding in and out movement?

Not sure that I've seen one before, or it I did I may have skipped right over it without thinking about it.

A.D. Miller
02-26-2009, 08:16 AM
Fred,

However, that receptacle, if present, is not intended to satisfy 210.52(C)(2) but to be 'in addition to', which is allowed. :)

However, as the installation has been revised from being cord and plug connected to being permanently-wired, and is on the two small appliance circuits, what say you?

Aaron,

Were you able to see that it was not cord and plug connected?

You stated that this was a drawer type microwave, indicating that it slides in and out(?), in which case permanent wiring would need to allow for that flexibility, or, are you meaning it - as a unit - replaced a 'drawer' and was fixed in place with no sliding in and out movement?

Not sure that I've seen one before, or it I did I may have skipped right over it without thinking about it.

JP: OK, I could not ascertain the power connection. I assumed it was hard wired because the unit was permanently installed in the cabinet, i.e. you would need a bag of tools to remove it.

http://www.wolfappliance.com/resources/products/downloads/QR_MWD24.pdf

It is another one of those whizbang appliances for the "Sharper Image" morons who don't cook. Much like the "thermographers" in our business, these folks are under-qualified and over-equipped. But, I digress, in my usual fashion.

Back to the point: Was this a compliant installation if:

1. It was cord and plug connected
2. Hard wired

It seems inconvenient at best. If you had a coffee pot running on the wall counter, the microwave running at the island, and you were operating a big mixer simultaneously, it might trip. Then you would have to reset the clock in the microwave. Of course, these guys will never be cooking more than popcorn or Chinese reheat in the oven, so it's a moot point.

Jerry Peck
02-26-2009, 08:44 AM
Then you would have to reset the clock in the microwave.

You are worried about the clock on the microwave?

What about the clock on the coffee maker that tripped the circuit? :)

Or the clocks on all the other appliances which now come equipped with clocks so they can make breakfast and have it ready when you get up and walk into the kitchen? :)

Heck, what the manufacturers need to do is make those clocks communicate wirelessly with each other, set one, press a 'reset all' button and all other clocks reset to that time ... Oh Dang! ... I just gave away another invention! ... No wonder I never make any money.

Jerry Peck
02-26-2009, 08:56 AM
Back to the point: Was this a compliant installation if:

1. It was cord and plug connected
2. Hard wired


The answer to your question is here: http://www.wolfappliance.com/resources/products/downloads/DrawerMicrowaveInstall.pdf

On page 9: (underlining is mine)
- ELECTRICAL REQUIREMENTS
- - ELECTRICAL OUTLET LOCATION

- - - The electrical requirements are a 120 volt 60 Hz, AC only, 15 amp or more protected electrical supply. It is recommended that a separate circuit serving only this appliance be provided.
- - - The drawer is equipped with a 3-prong grounding plug. It must be plugged into a wall receptacle that is properly installed and grounded. Should you only have a 2-prong outlet, have a qualified electrician install a correct wall receptacle.
- - - NOTE: If you have any questions about the grounding or electrical instructions, consult a qualified electrician or service person.

Roland Miller
02-26-2009, 08:56 AM
The drawer microwave
can also be installed
using an electrical
outlet in an adjacent
cabinet within the area
where the provided
electrical cord can
reach. Power cord
access hole in cabinet
should be a minimum
11/2" (38) diameter
hole and deburred of
all sharp edges.
E L E C T R I C A L OU T L E T LOC AT ION
The electrical requirements are a 120 volt 60
Hz, AC only, 15 amp or more protected electrical
supply. It is recommended that a separate
circuit serving only this appliance be provided.
You must follow
all National
Electrical Code
regulations. In
addition, be aware
of local codes and
ordinances when
installing your
service.

A.D. Miller
02-26-2009, 09:04 AM
You are worried about the clock on the microwave?

JP: Yes, it was a real bear to reset.


What about the clock on the coffee maker that tripped the circuit?

JP: Coffe makers are optional equipment.



Or the clocks on all the other appliances which now come equipped with clocks so they can make breakfast and have it ready when you get up and walk into the kitchen?


JP: Also extraneious appliances.

[QUOTE]Heck, what the manufacturers need to do is make those clocks communicate wirelessly with each other, set one, press a 'reset all' button and all other clocks reset to that time [/QUOTE

JP: Agreed.

A.D. Miller
02-26-2009, 09:06 AM
Pardon the lack of spell checking on that last post - laziness.

Roland Miller
02-26-2009, 09:39 AM
It has been shown that you can leave out and misspell over 1/3 of the text and almost everyone reads it as though everything was correct. But I known it draws ire and fire on this board...:D

Jerry Peck
02-26-2009, 10:51 AM
It has been shown that you can leave out and misspell over 1/3 of the text and almost everyone reads it as though everything was correct. But I known it draws ire and fire on this board...:D


Indo't konw waht you are tlainkg auobt. :)

H.G. Watson, Sr.
02-26-2009, 12:01 PM
A.D. Miller,

You are looking at the wrong source of information to develop your answer, although the location required for the electrical connection to install this appliance and this appliance's nature already makes it non-compliant to share the either of the required circuits.

The language in the code is quite precise that sharing to this location is not permitted within the cabinetry back side under the countertop, and since the microwave is neither a CLOCK nor a gas-fired cooking appliance it does not meet that exception. Can expand on that later if you wish.

However, the correct source of information that easily identifies this appliance is not permitted to share the SA circuits is this particular appliance's POWER RATING.

Both the 24" and the 30" drawer microwaves from wolf have identical power ratings. Although the appliance provides 950 watts of "cooking power", the POWER RATING for this appliance is 1.5 kW or 1500 watts. You can find this information on the identification plate of the appliance. You can also see this information is available on page 2 (on the Left side about half way down the page) of the following (Technical Specifications)document:

http://www.wolfappliance.com/resources/products/downloads/QR_MWD24.pdf

This exceeds 50% of the circuit's rating (20 Amps), therefore this "installed" appliance may not share. Previous citations already provided.

So, yes there is a problem with the situation you described, and no it may not be powered by either small appliance circuit.

A.D. Miller
02-26-2009, 12:08 PM
A.D. Miller,

You are looking at the wrong source of information to develop your answer, although the location required for the electrical connection to install this appliance and this appliance's nature already makes it non-compliant to share the either of the required circuits.

The language in the code is quite precise that sharing to this location is not permitted within the cabinetry back side under the countertop, and since the microwave is neither a CLOCK nor a gas-fired cooking appliance it does not meet that exception. Can expand on that later if you wish.

However, the correct source of information that easily identifies this appliance is not permitted to share the SA circuits is this particular appliance's POWER RATING.

Both the 24" and the 30" drawer microwaves from wolf have identical power ratings. Although the appliance provides 950 watts of "cooking power", the POWER RATING for this appliance is 1.5 kW or 1500 watts. You can find this information on the identification plate of the appliance. You can also see this information is available on page 2 (on the Left side about half way down the page) of the following (Technical Specifications)document:

http://www.wolfappliance.com/resources/products/downloads/QR_MWD24.pdf

This exceeds 50% of the circuit's rating (20 Amps), therefore this "installed" appliance may not share. Previous citations already provided.

So, yes there is a problem with the situation you described, and no it may not be powered by either small appliance circuit.

HG: Can you send me the code citation on that?

H.G. Watson, Sr.
02-26-2009, 12:11 PM
JP: OK, I could not ascertain the power connection. I assumed it was hard wired because the unit was permanently installed in the cabinet, i.e. you would need a bag of tools to remove it.

http://www.wolfappliance.com/resources/products/downloads/QR_MWD24.pdf

It is another one of those whizbang appliances for the "Sharper Image" morons who don't cook. Much like the "thermographers" in our business, these folks are under-qualified and over-equipped. But, I digress, in my usual fashion.

Back to the point: Was this a compliant installation if:

1. It was cord and plug connected
2. Hard wired

It seems inconvenient at best. If you had a coffee pot running on the wall counter, the microwave running at the island, and you were operating a big mixer simultaneously, it might trip. Then you would have to reset the clock in the microwave. Of course, these guys will never be cooking more than popcorn or Chinese reheat in the oven, so it's a moot point.

No. It would not be compliant either way. It is not the electrical connection being permanent or cord-and-plug-connected that determines "fastened in place" in this case, it is the fastening of the appliance itself to the cabinetry which is fixed in place/permanent. The Fixed-in-place utilization equipment's power rating is 1.5 kW. That exceeds 50% of the circuit's rating.

Ted Menelly
02-26-2009, 12:39 PM
It has been shown that you can leave out and misspell over 1/3 of the text and almost everyone reads it as though everything was correct. But I known it draws ire and fire on this board...:D

Harvard study. A bit more involved but they did do a study on misspelled words being read correctly.


I must draw a bit of fire because I am always doing something else when I am reading or replying to posts and screw everything up.

Shoot. No one knows what I am talking about half the time anyway. Oh well, I do:D

H.G. Watson, Sr.
02-26-2009, 12:51 PM
HG: Can you send me the code citation on that?

2008 NEC Citations (I quoted and highlighted some of these previously and cited some of these already, esp. post 12 above).

100 "Appliance"
100 "Branch Circuit, Appliance"
220.10
210.11
210.11(C)(1)
210.19(A)(4)
210.21(B)(1)
210.21(B)(2)
Table 210.21(B)(2)
210.23
210.23(A) and including especially the exception
210.23(A)(1)
210.23(A)(2)
210.52
210.52(B)
210.52(B)(1) and including the exceptions
210.52(B)(2) and including the exceptions.
210.52(C)(5) and including the exception.
422.1
422.10
422.10(A)
422.10(B)
422.11
422.16(A)
422.33 (A) or in the alternative 422.31
422.35
422.60(A)
422.60(B)
422.62

You can view the unammended 2008 NEC (NFPA 70) on line at
NFPA 70: National Electrical CodeĀ® (http://www.nfpa.org/aboutthecodes/AboutTheCodes.asp?DocNum=70&cookie%5Ftest=1)
You can sign up at no cost to view for free.

Jerry Peck
02-26-2009, 02:00 PM
Aaron,

Along with the installation instructions use this: (underlining is mine)

NEC 110.3(B) Installation, and Use of Equipment. It is required to be installed and used in accordance with its listing and labeling.
- 110.3 Examination, Identification, Installation, and Use of Equipment.
- - (B) Installation and Use. Listed or labeled equipment shall be installed and used in accordance with any instructions included in the listing or labeling.

Part and parcel of that are the installation instructions, which say to put it on its own circuit. As installed at this time, that is not installed in accordance with its listing and labeling instructions, and that in and of itself is a code violation.

A.D. Miller
02-26-2009, 02:46 PM
Aaron,

Along with the installation instructions use this: (underlining is mine)

NEC 110.3(B) Installation, and Use of Equipment. It is required to be installed and used in accordance with its listing and labeling.
- 110.3 Examination, Identification, Installation, and Use of Equipment.
- - (B) Installation and Use. Listed or labeled equipment shall be installed and used in accordance with any instructions included in the listing or labeling.

Part and parcel of that are the installation instructions, which say to put it on its own circuit. As installed at this time, that is not installed in accordance with its listing and labeling instructions, and that in and of itself is a code violation.

JP and HG: OK . . . I'll be back after I crawl out from under this last load of citations . . .;)

A.D. Miller
02-27-2009, 04:25 AM
Be patient, I'm still reading . . .