DIY Chatroom Home Improvement Forum

DIY Chatroom Home Improvement Forum (http://www.diychatroom.com/)
-   Electrical (http://www.diychatroom.com/f18/)
-   -   20 amp outlet (http://www.diychatroom.com/f18/20-amp-outlet-173826/)

FrankLa 03-07-2013 11:20 AM

20 amp outlet
 
Can I run a 20 amp. Circuit for both the fridge and the dishwasher? Or do I need 2 - 20 amp. Circuits?

Hardway 03-07-2013 03:01 PM

Quote:

Originally Posted by FrankLa (Post 1131718)
Can I run a 20 amp. Circuit for both the fridge and the dishwasher? Or do I need 2 - 20 amp. Circuits?

By code you need 2 20 am circuits.:thumbsup:
Someone will correct me if I am wrong!

Glennsparky 03-07-2013 03:11 PM

If I remember right, as long as the combined amps are less than 16.5 (80% of 20A). And if one is hard wired, (no plug) it can't draw more than 50% of the circuit's amps. It's ok. However, this leaves no capacity for larger units. So, it's a perfect time to run a MultiWire Branch Circuit(MWBC). Run 12/3 with ground on a double pole breaker. Then at the first box split it into two 20A circuits.

rrolleston 03-07-2013 03:35 PM

Since it's a fridge I would just run two circuits one for each. If something ever happens and your dishwasher trips a breaker when you are not around it would cause your fridge to lose power on a MWBC.

Glennsparky 03-07-2013 03:54 PM

Rrolleston is correct on the technicals. But I would only be concerned if this circuit were AFCI or GFCI. Since this circuit requires neither, the breaker will probably never trip. And people seldom run the dishwasher when they're away on vacation, so most people would notice the fridge was out within a few hours.

Speedy Petey 03-07-2013 04:04 PM

OK, here is the scoop.

The refer can be on the SABC (small appliance circuit), OR it can be on a 15 or 20A INDIVIDUAL circuit. Meaning dedicated.
The DW can be on a 15A circuit, or a 20A circuit which can typically also then be shared with a disposal.

You CANNOT share the refer and DW.

See NEC 210.52(B)

darren 03-07-2013 04:08 PM

Quote:

Originally Posted by Glennsparky (Post 1131873)
If I remember right, as long as the combined amps are less than 16.5 (80% of 20A).

Why can't you load a 20A breaker up to 20A.

Speedy Petey 03-07-2013 04:13 PM

Quote:

Originally Posted by darren (Post 1131916)
Why can't you load a 20A breaker up to 20A.

Because you can. :thumbsup:

dmxtothemax 03-07-2013 04:45 PM

Quote:

Originally Posted by darren (Post 1131916)
Why can't you load a 20A breaker up to 20A.

In real life you can !
But it may or may not work reliably,
chances are you will get nuisance tripping
thats why they say only load breakers to 80%
This is as far as you can push them reliably.

And thats why its been made code.

jbfan 03-07-2013 04:54 PM

Quote:

Originally Posted by dmxtothemax (Post 1131951)
In real life you can !
But it may or may not work reliably,
chances are you will get nuisance tripping
thats why they say only load breakers to 80%
This is as far as you can push them reliably.

And thats why its been made code.

Can you post some facts and studies on this.

I've run 20 amp breakers at 22 amps for hours and never had a trip.
If a breaker is rated for 20, it should run 20 forever.

darren 03-07-2013 05:02 PM

Quote:

Originally Posted by dmxtothemax (Post 1131951)
In real life you can !
But it may or may not work reliably,
chances are you will get nuisance tripping
thats why they say only load breakers to 80%
This is as far as you can push them reliably.

And thats why its been made code.


80% rule has nothing to do with reliability. 80% is for continuous loads and this is done to prevent heat build up on the terminals.

If your breaker is rated at 100% you can run that breaker at full amperage forever with no real concerns.

Speedy Petey 03-07-2013 06:00 PM

Quote:

Originally Posted by dmxtothemax (Post 1131951)
In real life you can !
But it may or may not work reliably,
chances are you will get nuisance tripping
thats why they say only load breakers to 80%
This is as far as you can push them reliably.

And thats why its been made code.

Sorry DMX, this is completely false. Especially the the code part.

Glennsparky 03-07-2013 06:02 PM

Quote:

Originally Posted by Speedy Petey (Post 1131915)
...
You CANNOT share the refer and DW.

See NEC 210.52(B)

Ok, I read it. There is no language restricting fridge and DW on the same 20A circuit. An individual 15A circuit is permitted for the fridge. But the code allows unlimited SABCs (... two or more ... 210.11(C)(1)). So any 20A circuit just becomes another SABC. I stand by my original posts.

Speedy Petey 03-07-2013 06:06 PM

Quote:

Originally Posted by Glennsparky (Post 1131999)
Ok, I read it. There is no language restricting fridge and DW on the same 20A circuit. An individual 15A circuit is permitted for the fridge. But the code allows unlimited SABCs (... two or more ... 210.11(C)(1)). So any 20A circuit just becomes another SABC. I stand by my original posts.

But the DW CANNOT be on a SABC. NOR can it be on with the refer.

k_buz 03-07-2013 06:13 PM

I would read the specs for the dishwasher. They usually tell you exactly what the dishwasher can be powered by and the manufacturer specs trump the NEC.


All times are GMT -5. The time now is 09:20 PM.


Copyright 2003-2014 Escalate Media LP. All Rights Reserved