# split receptacle for fridge & microwave?



## Stubbie (Jan 7, 2007)

I see no reason why you cant have both on a 20 amp circuit. I guess I'm not following the reasoning behind your split receptacle idea for these two appliances. There are three codes that you must be concerned with NEC 210.21(B)(2), 210.23(A)(1), 210.23(A)(2), if the microwave is cord and plug then 23(A)(2) is not applicable. However if you put the microwave on a counter top then if it shares the duplex receptacale with the fridge it will have to be a gfci type receptacle or gfi breaker in the panel.

roger


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## Beren (Apr 27, 2007)

The fridge is an inductive load, isn't it? Won't it draw more than the listed 5-6 amps when the compressor starts?


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## DCK (Jul 25, 2007)

You are correct.:yes:

The standard rule of thumb for motor devices, when sizing an emergency power generator, is that all such electrical circuits be considered to draw 3 times their normal current on start up.

Example: Your 5 amp fridge would draw @ 15 amps. So were the microwave on the circuit total is 27 amps, which is not good.

So unless you want to constantly manage the operation of the fridge it would be best to keep the m/w off any motorized outlet

Good luck with it.

Dave


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## Beren (Apr 27, 2007)

DCK:

So my original thought to use a split-wire receptacle 
is rational in this context (as it would provide 20A dedicated to each outlet) , but I need to make sure the microwave is not on what can be classified as "kitchen coutertop" or I need a GFI on its circuit?


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## DCK (Jul 25, 2007)

First “google” Stubbie’s cited NEC codes & read such. 

I built my house & wired it back in 1977 to NEC code. Since my book is 30 years old it obviously would not be ethical for me to give you *precise *instructions from it. 

And with @ 40 years in telecommunications I have power wired equipment that the wire size ranged from #18awg, for data circuits, to 750 mcm (a cable with @ a 5” copper circumference) for central office power boards so you can take my following recommendation as *general *instruction.

Knowing little of your particular circumstance it is my opinion that you would be wise to dedicate a receptacle for the m/w even though a split receptacle may meet 2007 NEC code. 

Good luck with it.


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## Stubbie (Jan 7, 2007)

It is quite common to catch the fridge and a countertop microwave on one 20 amp circuit. Start up currents for a refrigerator last around .4 seconds before falling back to running amps of 5 or 6. This will not trip the breaker if the microwave is running at the same time or vice versa. You are not creating a locked rotor condition where the breaker will trip if the start current is sustained long enough to trip the breaker whether or not the circuit is shared by another appliance. If you dedicate a 20 amp circuit to the fridge and a 20 amp to a portable microwave using a multiwire your wasting a heck of a lot of power usage. 

A split receptacle is very common for a cord and plug dishwasher and waste disposal where each appliances sum currents can exceed 20 amps running . 

If what you are worried about were an issue then you would have trouble plugging your 12 - 15 amp vacumm sweeper into the general receptacles in the rest of your house.

Remember code requires that the kitchen be served with at least two small appliance 20 amp circuits. These circuits are also required to serve the refrigeration equipment. So unless you dedicate the fridge to 20 amps your going to be sharing it with the countertop or other appliances for kitchen use anyway.

You are over-thinking the inductive load of a refrigerator. 

This is of course your house and a split receptacle will certainly work I just think your wasting a lot of power dedicating 20 amps to each appliance.

And you have an issue with gfci for the microwave how will you do that with a split duplex receptacle?

I would only add if you do this multiwire make the microwave a self protected gfci receptacle by making it your end of run and the fridge on a non-gfci receptacle.....two duplexes instead of one split.

Stubbie


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## Beren (Apr 27, 2007)

This issue came to the front when our first microwave died. The fridge kicked on; the microwave gasped and died.

The house we're renting is strange, and the more I learn about code the more I find is not up to current standards. Then again, the house was built in the 1950's.

There is currently a single 15A circuit supplying the fridge, basement washing machine, and some other basement outlets. (I believe current code requires that laundry circuits be dedicated to the laundry area.)

The kitchen only has one 20A appliance circuit, iirc, but I will double-check. The other circuit (which also feeds other outlets and some lights, I need to refer back to the panel diagram) has receptacles at floor level and is not GFI protected. Also, actually using them would block foot traffic through the kitchen. Putting the microwave on the 20A appliance circuit would take up most of the countertop. That space is currently needed for food preparation!

I asked the landlord the cost for a split-wire recep so I could get the fridge/mw off the shared laundry circuit. I should have mentioned that bit from the start.

Are landlords required to keep rental properties up to current code?


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## DCK (Jul 25, 2007)

About 10 years ago I was shown a refrigerator plug that had partly melted. 
The 20 amp breaker served both refrigerator & the m/w. 
So I ran a dedicated line to the m/w. 
But the owner bought another refrigerator & put the old refrigerator in the garage fearing the plug & age of the refrigerator.
Today his new refrigerator plug looks the same as when he bought it.
And the that 30 year old refrigerator, it is still trucking.

Beren,

Usually, but not always, any code compliance update is left up to the seller/buyer when there is a transfer of property. Check with your city/county people for more information about your situation.


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## Stubbie (Jan 7, 2007)

Dck...I respectfully submit that you are not correctly pin pointing the fault of that fridge plug melting. It is not due to sharing a 20 amp circuit with a fridge and microwave. Plugs melt because of loose connections and the build up of heat not because of shared loads. The breaker or fuse protects the wiring before it gets too hot, of course things have to be properly protected with the correct ocpd.

DCK...If I had a microwave (12 amps) and and a electric skillet (12 amps) on a properly installed and 20 amp protected branch circuit would the plug melt because of this? BTW this is going to produce way more heat at the plug than the situation we are discussing here.


Beren:

A microwave doesn't fail/go bad because a fridge starts while on the same circuit.

There is no obligation for the land lord to update the electrical to 2005 code standards. If you are having difficulties with appliances failing and/or breakers/fuses opening then the landlord should have an electrician take a look at the electrical and the loads connected to the problem branch circuits. 


Your current wiring is typical of that era. To this I would agree that a 15 amp breaker may be pushing its limit to operate a fridge and a washing machine at the same time. The running amps would exceed the branch circuit rating in that screnario.

stubbie


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## Beren (Apr 27, 2007)

Thanks. I got home and rechecked my notes. It's a 20A breaker, but it also supplies something for the furnace.


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## terryfitz (Aug 22, 2008)

Sorry to correct you Stubbie, but the refrigerator can, and I think should be on a separate circuit. NEC 210.52B1x2 Personally, I have always done it this way since a GFCI tripping a refridge wouldn't be known until someone opened the door or started to smell something. Unfortunately, the 2008 is now requiring that even those receptacles that are not readily accessible in the garage and basement where you might have a freezer plugged in are now to be GFCI.


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## Speedy Petey (Feb 1, 2004)

terryfitz said:


> Sorry to correct you Stubbie, but the refrigerator can, and I think should be on a separate circuit. NEC 210.52B1x2


True, but there is nothing non-compliant about have the fridge on with a counter micro.

Of course it's not the best setup, but definitely IS legal.

210.52(B)(1) *specifically* allows the refer on one of the S-A circuits.
210.52(B)(1) Exc.2 *specifically* allows the refer on a dedicated 15 or 20A circuit if the installer desires.


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## terryfitz (Aug 22, 2008)

Thanks Pete. I agree with you. If I read Stubbie correctly, he said that the fridge HAD to be on the GFCI circuit which it doesn't. If I misread, I'm sorry.


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## SD515 (Aug 17, 2008)

One thing I haven't seen discussed that I'll add is that if you are going to use a split duplex receptacle (on the same yoke) your 20A 2 pole breaker you mentioned will have to have a listed handle tie so both poles are shut off at the same time. Just FYI.


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## terryfitz (Aug 22, 2008)

Question SD. You mention using a listed handle tie which seems like a good idea, but in the NEC 2104B it doesn't specify a listed handle. Have you found inspectors to demand this? Several times I have just used some #12 and not gotten red tagged. This is a genuine question on my part, not an argument. Of course the 2 pole GFCI is already bonded.


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## Super33 (May 15, 2008)

I have had several inspectors require a two pole breaker for a network on a duplex outlet, (usually being a 15A dish/disp duplex under a sink). Although most inspectors around here don't require it.


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## SD515 (Aug 17, 2008)

terryfitz said:


> Question SD. You mention using a listed handle tie which seems like a good idea, but in the NEC 2104B it doesn't specify a listed handle. Have you found inspectors to demand this? Several times I have just used some #12 and not gotten red tagged. This is a genuine question on my part, not an argument. Of course the 2 pole GFCI is already bonded.


It's a good question Terry. First, I should have said 'identified' and not 'listed'. My bad. I do have one inspector that is a 'listed' fanatic, I guess it just stuck in my head today...sorry. In general the inspects here do require us to use correct handle ties or a brkr with a factory made tie, pin, internal etc. We can't slip the nail or wire pass them....but we do get a laugh sometimes when we ask the 'newbie' put a nail in to make a 2 pole.:laughing: We know the inspect will catch it.

In reference to your mention of 210.4(B)...we asked an inspect once and his logic was 240.20(B)(1) which states '...with or without identified handle ties...' so he says 'if you have to tie them together, you have to use a tie identified for the purpose'. Then he laughed and pulled the nail out. (It wasn't my job...I just happen to be there dropping material...but I laughed too)


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## BigJimmy (Jun 30, 2006)

terryfitz said:


> Sorry to correct you Stubbie, but the refrigerator can, and I think should be on a separate circuit. NEC 210.52B1x2 Personally, I have always done it this way since a GFCI tripping a refridge wouldn't be known until someone opened the door or started to smell something.


I have already submitted the following appeal to the CMP for the next code cycle:

_When a refrigerator shall be used to chill beer and other alcoholic beverages, it shall be wired directly to the nearest service point in concrete encased RGS conduit with the circuit being protected solely by the governing utility's primary-side protective devices. Circuit conductors shall be 350kcmil or greater to avoid any potential voltage drop that may compromise the ability of the compressor to maintain the beverages at optimal temperature. No other devices shall be allowed to share this outlet. A SDS will be required to maintain operation of the refrigerator in the event of a loss of utility supply and will be designed to provide a minimum of 365 days power delivery._

So far, some have accused me of being a bit generous with the 365-day requirement. I has been argued (quite compellingly, I may add) that if the power was lost for any non-trivial amount of time, the HO would likely have nothing to do which would result in him/her/they drinking all of the alcoholic beverages within 6 hours after which the electric supply would be needless. I am willing to compromise with an 8 hour requirement which would allow the HO's time to eat all of the refrigerated non-beverage items following consumption of the beverages. Perhaps a FPN recommending that the HO maintain an emergency supply of dry snack foods for such a reason should be added?


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## J. V. (Jun 1, 2007)

terryfitz said:


> Thanks Pete. I agree with you. If I read Stubbie correctly, he said that the fridge HAD to be on the GFCI circuit which it doesn't. If I misread, I'm sorry.


Only if the fridge circuit shares counter top receptacles where GFCI protection is required. So in some instances the fridge must be on a GFCI. Not the best set up either.


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## Speedy Petey (Feb 1, 2004)

J. V. said:


> Only if the fridge circuit shares counter top receptacles where GFCI protection is required. So in some instances the fridge must be on a GFCI.


Absolutely not JV. There is NO instance where the fridge _must_ be on a GFI. 
It's not the circuit that must be protected, it's the receptacles serving counter spaces.
Unless of course it is a commercial kitchen.


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## Pudge565 (Jan 27, 2008)

DCK said:


> You are correct.:yes:
> 
> The standard rule of thumb for motor devices, when sizing an emergency power generator, is that all such electrical circuits be considered to draw 3 times their normal current on start up.
> 
> ...


Yes but you are forgetting the fact that it is a MWBC that he is talking about he will have 20 amps avalable on BOTH legs of the breaker. And the neutral will only carry the unbalanced current.


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## terryfitz (Aug 22, 2008)

I think a lot of the problem understanding the refrigerator circuit lies in the way the NEC lays out and explains the code for the small appliance circuits. For instance, if you carefully read 210.52B and C you would have no clue that the circuits supplying the countertops have to be GFCI. You have to go over to 552.41 to find that out. Another thing is that it reads you need two or more 20 ampere small-appliance circuits for the "kitchen, pantry, breakfast room, dining room, or similar area." With that in mind, it sounds like two circuits could take care of the whole shooting match. One circuit for the countertops; one for the rest of the place. Not so. In 510.11B3, it says that two circuits have to be provided for the countertops (GFCI although it doesn't SAY it there), and that these two circuits can provide power to the other areas as well. Anyway, the point is that you have to be a Philadelphia lawyer to read some of this stuff. Anybody want to expand on this?


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## Speedy Petey (Feb 1, 2004)

terryfitz said:


> I think a lot of the problem understanding the refrigerator circuit lies in the way the NEC lays out and explains the code for the small appliance circuits. For instance, if you carefully read 210.52B and C you would have no clue that the circuits supplying the countertops have to be GFCI.


Because 210.52 is required receptacles. Then they refer you to other sections of the code for more details about these required receptacles.




terryfitz said:


> You have to go over to 552.41 to find that out.


 Ummm, no, you go to 210.8.
552 is Park Trailers.




terryfitz said:


> Another thing is that it reads you need two or more 20 ampere small-appliance circuits for the "kitchen, pantry, breakfast room, dining room, or similar area." With that in mind, it sounds like two circuits could take care of the whole shooting match.


 Yup. This is true as the code minimum. Two S-A circuit for the receptacles in ALL those rooms, including the fridge. 




terryfitz said:


> One circuit for the countertops; one for the rest of the place.


 NO, it does not say that at all.




terryfitz said:


> Not so. In 510.11B3, it says that two circuits have to be provided for the countertops (GFCI although it doesn't SAY it there), and that these two circuits can provide power to the other areas as well.


 I have no idea where you are going with this one. The section you are referring to is 210.11(C)(1), and that refers you to 210.52.

Yes, it is kind of complicated, but it is what we have to deal with. Learn to decipher the code or remain a helper for the rest of your time in the trade.
Once you get used to reading it it's not all that hard.

_*(B) Small Appliances
(1) Receptacle Outlets Served* 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 floor receptacle outlets covered by 210.52(A), all countertop outlets covered by 210.52(C), and receptacle outlets for refrigeration equipment.



_


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## SD515 (Aug 17, 2008)

Big Jim...

Consider adding this line after the SDS requirement...

_In addition to the required SDS back-up unit, a supplemental back-up refrigerator shall also be required, in case of primary refrigerator failure. This SBUR shall be placed directly next to the main refrigerator unit, shall have an interior capacity capable of an 8 hour supply of such forementioned beverages, and used for no other purpose. This SBUR will be allowed to be plugged in the same receptacle as the main refrigerator unit, or on it's own individual branch circuit, provided a suitable transfer switching means to the main refrigerators circuit is also provided._

Exception: _The homeowner will not be required to maintain an emergency supply of dry snack foods if the homeowner's property is located within 3 feet of a 24 hour convenience store or the like.
_


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## BigJimmy (Jun 30, 2006)

SD515 said:


> Big Jim...
> 
> Consider adding this line after the SDS requirement...
> 
> ...


I agree but the snack food thing was a FPN, not an exception!


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## SD515 (Aug 17, 2008)

Ok...make it a FPN....Lol !! 

I'm still LMAO from your original suggestion :drink:


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