Cooking with less than 15 amps.

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Eli

Super Moderator | Elite Member
Oct 9, 1999
50,419
8
81
NL5 said:
Most small kitchen appliances are not 20 amps, hence, most kitchen plugs are not 20 amps. The circuit is 20 amps, so the breaker doesn't blow if two heavier drawing appliances are used at the same time.

edit - that 20 amp recep actually is a dual 15/20 amp (it will accept either plug)
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Yeah, I guess that's the problem. I'm well aware that my microwave and fridge aren't drawing anywhere near 2400W, lol. I guess I just never thought about it, because like I've said - even though I've seen the receptacles with the T shaped slot, I've never actually seen a male cord with a T shaped prong. Got any examples handy? Would be interesting..
 
NL5

NL5

Diamond Member
Apr 28, 2003
3,286
12
81
Eli said:
Yeah, I guess that's the problem. I'm well aware that my microwave and fridge aren't drawing anywhere near 2400W, lol. I guess I just never thought about it, because like I've said - even though I've seen the receptacles with the T shaped slot, I've never actually seen a male cord with a T shaped prong. Got any examples handy? Would be interesting..
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I've got power tools that have 20 amp plugs. A quick google search yields -


http://www.blendtec.com/productDetails.aspx?id=1340#

http://www.acetoolonline.com/Milwaukee-4096-Diamond-Coring-Clutch-Motor-p/mil-4096.htm

http://www.csunitec.com/masonry-too...hp?PHPSESSID=1a47368e81266850ae9a0f8e69297899
 
Rubycon

Rubycon

Madame President
Aug 10, 2005
17,768
485
126
TridenT said:
It gave both the VA and the W. It was like 1500VA and 900W or something.
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Right - the 1500VA UPS is often mistaken for 1500W. Plug a 1500W heater into it and see what happens. ;)

Even at 900W (full load) its batteries - in perfect condition - are only going to hold out for six to eight minutes before shut off. Some folks try adding ampacity by purchasing a pair of trolling batteries and boxes and yes this will increase runtime BUT! The inverter's heatsinks are WAY too small for continuous, full load operation and the unit will fail.

This is why UPS' with the extended run time option are much larger and often use forced air cooling. (they will have a noisy fan that runs whenever the inverter is in use)

RE: Kitchen wiring...

Many kitchens are wired with several 20A circuits (12AWG wiring, 20A CB) however have standard 15A receptacles. This allows for more than one appliance to run on the same circuit at the same time. You're not supposed to draw more than 15A out of that socket. Appliances that do will have a 20A plug, for example.
 
0roo0roo

0roo0roo

No Lifer
Sep 21, 2002
64,795
84
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camping-stove-300x300.jpg
 
S

ShawnD1

Lifer
May 24, 2003
15,987
2
81
NL5 said:
You're still wrong.

The time/current curve for a 15 amp breaker doesn't even START until 15 amps. Unless it is malfunctioning 13 amps will NEVER cause it to trip.

Also, you fail at reading code. Sorry. :)

You might wanna look at page 32 -

http://www3.sea.siemens.com/step/pdfs/mccb_2.pdf
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I think you read page 32 wrong. Look at the top of the graph on the left side. The trip curve on page 32 starts at 1x multiple of continuous rating. The NEC defines continuous as being 80% of the non-continuous rating on the mccb. 15 is the non-instantaneous rating. The continuous rating would be 80% of that, or 12A. The breaker begins the trip time at 12A and it trips faster as more load is added.
 
NL5

NL5

Diamond Member
Apr 28, 2003
3,286
12
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ShawnD1 said:
I think you read page 32 wrong. Look at the top of the graph on the left side. The trip curve on page 32 starts at 1x multiple of continuous rating. The NEC defines continuous as being 80% of the non-continuous rating on the mccb. 15 is the non-instantaneous rating. The continuous rating would be 80% of that, or 12A. The breaker begins the trip time at 12A and it trips faster as more load is added.
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Dude. Your combining two TOTALLY unrelated things. Seriously. You are wrong. The time current curve starts at 1x the rating for the BREAKER. A 15 amp breaker is rated for - wait for it - 15 amps. Crazy, I know.

edit - just to clarify a bit further. The NEC breaker sizing guidelines have to do with the circuit's capacity. If you have a 15 amp continuous load (as defined by the NEC) you cannot put a 15 amp breaker on that circuit. Which then means you cannot use a 14 AWG wire in that circuit either. None of this has anything to do with when a breaker will trip. The time/current curve is what determines when it will trip. As you can clearly see by the breaker curve for the breaker I posted the link to, t/c curves start at the breakers rated limit. Not before. BTW - an oven is not a continous load. Again, crazy, I know.
 
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Squisher

Squisher

Lifer
Aug 17, 2000
21,204
66
91
Someone was using the toaster oven this morning when I put some bacon bread into the toaster that was plugged into the same outlet as the toaster oven. It was unbelievable! Moments later I had some delicious toast to go with my scrambled eggs. I believe the items in the toaster oven were also unaffected by my electrical faux pas.
 
TridenT

TridenT

Lifer
Sep 4, 2006
16,800
45
91
ultimatebob said:
You worry too damn much about this. Just get a microwave, a hot plate, and a toaster oven and be done with it. As long as you don't try to use them all at the same time, you'll be fine!
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You say worry too much and then maybe I don't worry. Maybe I don't worry at all, and then what? I get into this environment with expectations that things will work just splendidly and what might happen then? Things won't work. Then what? I'm totally fucked as I figure out the problem, realizing to my total demise that I am without a reasonable solution to my problem that will last as long as my lease does or as long as I can manage to keep myself alive as I wait for the old wiring in that room to finally combust and consume me in flames as I try to cook my fuckin' frozen pizzas.
 
Ricemarine

Ricemarine

Lifer
Sep 10, 2004
10,507
0
0
TridenT said:
You say worry too much and then maybe I don't worry. Maybe I don't worry at all, and then what? I get into this environment with expectations that things will work just splendidly and what might happen then? Things won't work. Then what? I'm totally fucked as I figure out the problem, realizing to my total demise that I am without a reasonable solution to my problem that will last as long as my lease does or as long as I can manage to keep myself alive as I wait for the old wiring in that room to finally combust and consume me in flames as I try to cook my fuckin' frozen pizzas.
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Then...
http://www.amazon.com/Black-Decker-T...2833191&sr=1-1
 
B

BladeVenom

Lifer
Jun 2, 2005
13,365
16
0
Rubycon said:
UPS ratings are in Volt-Amperes, not Watts. That 900VA UPS would only handle about 550 watts. See here for more detail - http://test.power-solutions.com/watts-va.php

The outputs are also not a true sine wave which further complicates matters making it impossible to strap their outputs together increasing capacity.

Furthermore at full load that UPS' battery would be exhausted in just a few minutes at best. The charging circuit will take 8 hours (or more) to fully charge a completely discharged battery/batteries.

If you are powering a resistance heater it can run off pure direct current. Ten 12V 105Ah deep cycle batteries in series can run several heating appliances at the same time - waffle irons, toaster ovens, etc. As long as they have electromechanical timers and bi-metal thermostats (nothing digital that's expecting an initial AC input to the power cord) it will work. Of course keep in mind that a battery bank of that size requires proper care (particularly if using non SLA/AGM aka flooded design!) and a decent charger, etc.
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That's a good point, and one I was checking to see if anyone had pointed out yet.

My 1500 VA UPS couldn't even run my toaster without giving me the overload warning. So no heating pop tarts at my computer desk. :(
 
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ebaycj

ebaycj

Diamond Member
Mar 9, 2002
5,418
0
0
TridenT said:
Yikes. 1800W might be too much... I gotta stay under 15A.
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Not to mention, if you don't mind going out of code (a little bit), it is very likely that if you replace your 15A breaker with a 20A breaker, nothing bad will happen. The wires may get a little warm under times of extremely high stress but that is likely all. Don't try anything higher than 20A though.

Worked for us on the rental house in college with multiple window AC units going on the same circuit.
 
ultimatebob

ultimatebob

Lifer
Jul 1, 2001
25,134
2,450
126
TridenT said:
You say worry too much and then maybe I don't worry. Maybe I don't worry at all, and then what? I get into this environment with expectations that things will work just splendidly and what might happen then? Things won't work. Then what? I'm totally fucked as I figure out the problem, realizing to my total demise that I am without a reasonable solution to my problem that will last as long as my lease does or as long as I can manage to keep myself alive as I wait for the old wiring in that room to finally combust and consume me in flames as I try to cook my fuckin' frozen pizzas.
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Geez... just get an electrician to wire another outlet from the circuit breaker if you're so worried about it.

Of course, you're certainly welcome to try cooking something with a charcoal grill with the doors and windows closed as well. That should make for a good ATOT post a few weeks from now :)
 
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TridenT

TridenT

Lifer
Sep 4, 2006
16,800
45
91
ultimatebob said:
Geez... just get an electrician to wire another outlet from the circuit breaker if you're so worried about it.

Of course, you're certainly welcome to try cooking something with a charcoal grill with the doors and windows closed as well. That should make for a good ATOT post a few weeks from now :)
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Because I feel like spending all that money with no return on my investment.
 
NL5

NL5

Diamond Member
Apr 28, 2003
3,286
12
81
It has 15 amp plug, so it will be fine on a 15 amp breaker as long as nothing else is running on that circuit. I'd figure out what else is on that circuit. Most houses have the kitchen plugs on a dedicated circuit - been code for a long time.
 
TridenT

TridenT

Lifer
Sep 4, 2006
16,800
45
91
Capt Caveman said:
Why would you spend that much money for that? I've already given you a link to the same thing for a lot less money.
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It's the #1 toaster oven, that's why. I'll be using this thing as my sole cooking thingy for over 3 years!
 
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