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  #1  
Old 10-07-2004, 09:32 AM
js_africanus js_africanus is offline
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Why can't I plug my microwave into the same outlet as my refridgerator?

Hi.

I'm in a new place in an old building. My kitchen only has one outlet. The microwave instructions are clear that I don't plug it into the same outlet as the fridge or the stove. The stove is gas, but the fridge is electric. Why can't I use the same outlet? What happens if I do?
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  #2  
Old 10-07-2004, 09:44 AM
Grey Grey is offline
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You'll blow the fuse or circuit breaker since the combined current draw of the two appliances is greater than most homes are wired for.
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  #3  
Old 10-07-2004, 10:46 AM
The Great Sun Jester The Great Sun Jester is offline
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2 kinds of wire typically used in homes. 14 gauge for 15 amp circuits, and 12 gauge for 20 amp circuits & 220v outlets (Real Men don't bother with 14 gauge, they just run 4 strand 12 gauge throughout the house ). If you pump more amps through the wire than it's supposed to carry, the wire will overheat and destroy the insulation over time. They also get pretty brittle making it a pain in the butt to work with when it's time to change an outlet. To prevent this damage, the circuit breaker will trip (blow a fuse, if you prefer the ancient verse) when more than the designated amount of juice gets pulled into the wire.

So anyway, refrigerators can pull up 20 amps (normally only during start up). Put one on a 15 amp circuit and it will be tripping that breaker fairly regularly so the "right" way to wire the fridge is to give it its own dedicated 20 amp circuit. Nothing else gets plugged in on the same circuit as Mr. Fridge.

The microwave likewise pulls quite a bit of juice, and depending on your breeding, you may have it on its own 15 amp circuit as well, or maybe plugged into a 20 amp circuit with something weak like a blender or coffee pot. Long and short is, do the math (which I foprget how to do) and determine the maximum amount of amps that can be pulled bu any appliances plugged into the circuit, and wire/breaker it accordingly.

Fridge & Microwave together on a circuit will result in many jaunts to the breaker box at best, damaged wiring and fires at worst.
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  #4  
Old 10-07-2004, 10:56 AM
Balthisar Balthisar is offline
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Quote:
Originally Posted by js_africanus
Hi.
I have a similar problem in my new (old) house. I ripped out the nasty, original stove hood (which was hard-wired for some reason that seems normal but strange to me), and installed a built-in microwave. I also replaced the original icky gas stove with an upper-mid-range, gas, slide-in. The problem is it's on the same circuit as my micro. The oven, it turns out, has an electric "helper" element that's in use to aid in browning. I thought my microwave was going bad when the breaker tripped as I tried using them simultaneously.
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  #5  
Old 10-07-2004, 10:57 AM
David Simmons David Simmons is offline
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Check you breaker or fuse panel to the the capacity of the kitchen outlet plug. If it is 15 Amps you might have a problem. My microwave is a 1000 watt unit and so takes at least 8 Amps. at 120 volts. I don't want to bother looking at the nameplate so I don't know the exact number but a WAG would be between 9 and 10. On a 15 Amp. circuit breaker this only leaves 5 to 6 for any other appliance.

And incidently, our kitchen outlets are wired for 20 Amps. The refrigerator and microwave have been connected to the same breaker for several years with no problems.

Actually if the combined current of the two appliances exceeds the circuit breaker or fuze capacity you can't even plug them into any outlet on the same circuit. If you had more than one outlet in the kitchen then chances are that they would be connected to the same circuit breaker so a different outlet wouldn't do any good.

If you have to run an extension cord from an outlet on another circuit I would put the oven on the extension. You are around when using the oven and can watch for any problems with the extension. That's not the case with the refrigerator. Use an extension cord with enough capacity. The current requirement for the oven should be on the nameplate on the back of the unit.
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  #6  
Old 10-07-2004, 11:13 AM
js_africanus js_africanus is offline
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Quote:
Originally Posted by Inigo Montoya
If you pump more amps through the wire than it's supposed to carry, the wire will overheat and destroy the insulation over time....damaged wiring and fires at worst.
Fire was/is my big concern. I was wondering if too much energy through the outlet might cause a fire; but, the wiring is close enough for me. The alternative of shutting the whole house down everytime I want to warm a frozen burrito didn't sound too appealing either. (Of course, I don't know if that would happen—maybe it'd just be me or my kitchen.) The landlord happened to call me this morning, so I asked him about it. He said that he'd consult an electrician.

I was wondering about an extension cord. I nice fat one. I have two outlets in the living room, neither are doing any work. Since, as pointed out, I'll be w/ the microwave when it's in use, I can make the extension cord a nice, workable option for the time being.

Cool. Thanks.
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  #7  
Old 10-07-2004, 12:50 PM
enipla enipla is offline
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Quote:
Originally Posted by David Simmons
If you have to run an extension cord from an outlet on another circuit I would put the oven on the extension. You are around when using the oven and can watch for any problems with the extension. That's not the case with the refrigerator. Use an extension cord with enough capacity. The current requirement for the oven should be on the nameplate on the back of the unit.
The oven is most certainly 220. So an extension from a regular outlet is out.

Those directions sound hokey. Aint' no way your going to plug the microwave into the same outlet as the stove anyway. And they should be talking circuts, not outlets.
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  #8  
Old 10-07-2004, 12:56 PM
Q.E.D. Q.E.D. is offline
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Quote:
Originally Posted by enipla
The oven is most certainly 220. So an extension from a regular outlet is out.
I've never seen a 220 V microwave oven in my life. I assume they must exist in Europe, but here?
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  #9  
Old 10-07-2004, 01:56 PM
The Great Sun Jester The Great Sun Jester is offline
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Quote:
Originally Posted by Q.E.D.
I've never seen a 220 V microwave oven in my life. I assume they must exist in Europe, but here?
You big old crazy! Not the friggin microwave oven, the other one that makes cookies and pizzas!
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  #10  
Old 10-07-2004, 02:03 PM
Q.E.D. Q.E.D. is offline
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Quote:
Originally Posted by Inigo Montoya
You big old crazy! Not the friggin microwave oven, the other one that makes cookies and pizzas!
Well, yes. But David Simmons was referring to the microwave, unless I'm mistaken.
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  #11  
Old 10-07-2004, 02:07 PM
js_africanus js_africanus is offline
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Whoa....the microwave is cool for an extension cord; but, the regular oven with the stove top and all, if it were electric instead of gas, would be a no-no for the extension cord. Am I following this correctly?
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  #12  
Old 10-07-2004, 02:14 PM
Q.E.D. Q.E.D. is offline
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Quote:
Originally Posted by js_africanus
Whoa....the microwave is cool for an extension cord; but, the regular oven with the stove top and all, if it were electric instead of gas, would be a no-no for the extension cord. Am I following this correctly?
Yes. That would be bad, even if you could do it. Which you can't because the plugs are different, and because most electric ranges use 240 V rather than 120 V.
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  #13  
Old 10-07-2004, 02:14 PM
The Great Sun Jester The Great Sun Jester is offline
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Quote:
Originally Posted by js_africanus
Whoa....the microwave is cool for an extension cord; but, the regular oven with the stove top and all, if it were electric instead of gas, would be a no-no for the extension cord. Am I following this correctly?
If said oven/stove has a 220v plug (and I'd bet your reputation that it does) the plu would be about the size of your fist and have 3 or 4 mammoth prongs pointing in all sorts of crazy directions. I've never seen an extension cord for a 220 plug. i suspect this is because there are none...commercially available that is. i'm sure I have relatives in Byhalia, MS. that have put something together.
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  #14  
Old 10-07-2004, 03:15 PM
David Simmons David Simmons is offline
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Quote:
Originally Posted by js_africanus
Whoa....the microwave is cool for an extension cord; but, the regular oven with the stove top and all, if it were electric instead of gas, would be a no-no for the extension cord. Am I following this correctly?
The question was about microwave ovens. Let's stick to one subject at a time and avoid confusion. There was no reason for anyone to even broach the subject of any other kind of oven.
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  #15  
Old 10-07-2004, 05:56 PM
Balthisar Balthisar is offline
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Quote:
Originally Posted by David Simmons
The question was about microwave ovens. Let's stick to one subject at a time and avoid confusion. There was no reason for anyone to even broach the subject of any other kind of oven.
For your reference, here's the OP (emphasis mine):

Quote:
Originally Posted by js_africanus
...The microwave instructions are clear that I don't plug it into the same outlet as the fridge or the stove.
Because they're often on the same circuit, some of the stove responses are perfectly adequate.
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  #16  
Old 10-07-2004, 08:18 PM
beltbuckle beltbuckle is offline
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Quote:
Originally Posted by Q.E.D.
Yes. That would be bad, even if you could do it. Which you can't because the plugs are different, and because most electric ranges use 240 V rather than 120 V.
You could safely create an extension cord for a 220v oven though. There are plenty of charts that say what gauge of wire to use to run how much power what distance. It would be some hefty wire though. I know you knew this, but others may not.

Though, I have never seen a house where it would be needed... almost every house has a properly wired circuit for just the oven.
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  #17  
Old 10-07-2004, 09:15 PM
Una Persson Una Persson is offline
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Quote:
Originally Posted by Inigo Montoya
If said oven/stove has a 220v plug (and I'd bet your reputation that it does) the plu would be about the size of your fist and have 3 or 4 mammoth prongs pointing in all sorts of crazy directions. I've never seen an extension cord for a 220 plug. i suspect this is because there are none...commercially available that is.
I not only have seen 220V extension cords, I have seen 440V extension cords. We personally own numerous 220V ones, including 220V power strips, trouble lights, and so forth. Of course, most of them are from England, but some not.
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  #18  
Old 10-07-2004, 10:38 PM
David Simmons David Simmons is offline
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Quote:
Originally Posted by Una Persson
I not only have seen 220V extension cords, I have seen 440V extension cords. We personally own numerous 220V ones, including 220V power strips, trouble lights, and so forth. Of course, most of them are from England, but some not.
Of course there can be 220 (or more accurately 240) V extension cords. All that is needed are plugs that fit the standard 240 V. outlets of which there are two varieties. Scroll down a little way.
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  #19  
Old 10-07-2004, 10:52 PM
Telemark Telemark is offline
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Is anyone reminded of "Green Acres"?

A three and a two and a two and a ...
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  #20  
Old 10-08-2004, 08:56 AM
js_africanus js_africanus is offline
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Quote:
Originally Posted by Telemark
Is anyone reminded of "Green Acres"?
"Green Acres" is where I'm moving from. My first week there I went to buy stamps and the woman at the counter gave me a $20 bill and asked me to go across the street for change. People actually got offended if they went to my folks' house when they weren't there and found the door locked.

Thanks to a genuine small-town atmosphere, being the county seat (hence sheriff's head office), and an alleged drug scandal involving a local airport just large enough for private planes from South America to land there, that town has more cops than your average village of 1,500 people.

The place I'm moving into now is in a small city...it's incorporated as a city, anyway. But the house was built in the 1800s. The stove/oven looks like it's from the 1940s. I had to ask my mom how to light the oven.
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  #21  
Old 10-08-2004, 12:11 PM
Capt B. Phart Capt B. Phart is offline
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Quote:
Originally Posted by Q.E.D.
I've never seen a 220 V microwave oven in my life. I assume they must exist in Europe, but here?
My "800w" 220-240v micro here in the UK says it's max power use is 3100w on the back panel (I guess when all it's convection/grilling elements are on while micro-ing) - my kettle is 3000w, toaster 1800w, espresso machine a mere 1500W (all within a standard UK 13 amp socket and so two can be plugged into the usual double outlet in the 32A ring-main - hurrah for 240 volt mains! stoves still get a dedicated feed, I'm guessing 20A)
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  #22  
Old 10-08-2004, 09:52 PM
spingears spingears is offline
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Quote:
Originally Posted by js_africanus
Hi. I'm in a new place in an old building. My kitchen only has one outlet. The microwave instructions are clear that I don't plug it into the same outlet as the fridge or the stove. The stove is gas, but the fridge is electric. Why can't I use the same outlet? What happens if I do?
Reason 1. A 15 amp. circuit won't support both units.
Reason 2. Voiding of warrantee.

Quote:
Originally Posted by Inigo Montoya
(Real Men don't bother with 14 gauge, they just run 4 strand 12 gauge throughout the house ).
Why not 2-#12 w/Ground instead of 4 #12's. That is assuming you meant 4-#12's.
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  #23  
Old 10-09-2004, 05:02 AM
EvilGhandi EvilGhandi is offline
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You guys are freaking me out.

There is no city, state or federal code that would allow a 110v fridge to run on the same circuit as a 220v oven. None, nowhere. Granted you could wire a 110v outlet on a 220v curcuit, just not legally. No electrician would ever do so.

A gas range is typically plugged into a 110v outlet for the sparker, dial lights and the little bulb in the oven. No big deal

The only exeption I have ever seen is on A/C circuits. There is often a pigtailed hot in a box wired for 110v. These however, are dedicated circuits with their own breakers.

It has also been a LONG time since I've seen a "range plug". (big ol honkin' outlet similar to a dryer) Though I admit Ive seen 50 amp 220v outlets with stoves plugged into them.

Local codes around here have required that Ranges, water heaters etc.. be on seperate circuits and breakers and all connections be made in boxes (hard wire) since the '60's

Here's an east way to test if the one outlet in your kitchen is on the same run as the fridge. (likely)

Open the door of the fridge and flip breakers until the light inside goes out. Plug something in to your kitchen outlet. If it works hey, different circuit. It's probably wired into the base run. Just dont run the vacuum at the same time.
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  #24  
Old 10-09-2004, 05:43 AM
unclviny unclviny is offline
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Jeez,
Don't you watch Green Acres?, the Fridge HAS to be at least a 12 and the Nuker is probably an 8, even Mrs. Douglas would know better.

Unclviny
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  #25  
Old 10-09-2004, 06:28 AM
t-keela t-keela is offline
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While it is true that the outlet probably wasn't designed for two appliances to run at the same time. The refrigerator doesn't run all of the time anyway. I'm not saying that it is okay to plug them both in but that's a fact. They wouldn't be ON at the same time except for coincidence.
You could however get a plug in surger that has a circuit breaker that kicks off when they do both come on. I've got one on my porch because I like to run a fan and/or stereo etc. also I use it to run Xmas lights off of. I wanted to have several outlets and this "box" plugs into the two outlets and has places for six. The breaker will kick if I'm pulling too many amps and all I have to do is reset it after I unplug or turn something off. There pretty cheap and you can get them at most hardware stores.
disclaimer: read the instructions before trying this.

Also..you may run the microwave on a extension cord but I wouldn't try it with the frig. good luck and be careful
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  #26  
Old 10-09-2004, 06:39 AM
t-keela t-keela is offline
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Hell, I've made extension cords for welders and power tools that were two hundred feet long. Granted I used some heavy romex and wired it into a double 60amp breaker with a heavy duty plug on the end but it can be done safely and legally.
In order to get the 110 off the 220 you just take the main ground and one of the hots and you've got 110. It won't work the other way since 220 requires three cycles and 110 is only two. Adding them together won't work and can be dangerous.
I am NOT advising anyone to try it. I'm just saying is all.

BTW I've never seen a 220V microwave either. Reckon how fast that sucker would melt your food.
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