What is the purpose of 15 amp breakers (excluding motor loads)

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Adamjamma

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Jamaica and london
what about a person who only wants 15 amp outlets in an area, and yet wants 12 wire on it due to the distance from the panel, such as 80 feet from panel in a rancher? Or bedrooms on third floor yet 60 feet away as well, straight line... in both cases the 12 is acceptable, and the 15 amps is acceptable as well.
Or is it a requirement to only use 20 amp circuit breakers on outlets now? I mean, I know 15 or 20 amp outlets can be used on a 20 amp circuit...
 
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Adamjamma

Senior Member
Location
Jamaica and london
ok.. never thought about that... sorry. Gues that is why UK uses 2.5 mm for outlets and 1.5 for lighting... which is like 12 or 13 gauge and 15 or 16 gauge..lol

I dont think sometimes but just do what I was taught... just so used to it...
 
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Craigv

Senior Member
Location
Boyertown, PA, USA
LarryFine said:
True, but since the load must be served, the usual result is a larger conductor, not a smaller OCPD.



I'm just saying . . .
Click to expand...

Yes, and in the examples of ambient temperature or bundled conductors, when the load served is at or below the 15 amp minimum available OCPD, the only option is larger conductor.

Potahto, potato...
 
mbrooke

mbrooke

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Adamjamma said:
ok.. never thought about that... sorry. Gues that is why UK uses 2.5 mm for outlets and 1.5 for lighting... which is like 12 or 13 gauge and 15 or 16 gauge..lol

I dont think sometimes but just do what I was taught... just so used to it...
Click to expand...


2.5mm2 is smaller than #12 which is 3.31mm2. 1.5mm2 is smaller than #14 which comes to 2.08mm2. Basically a wire that is about one gauge smaller and allowed to carry the same current if in contact with insulation- like the US.
 
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Adamjamma

Senior Member
Location
Jamaica and london
Well, the difference gets wierd when all your tables are for USA wire sizes and all you have is metric wire available. Then you are questioning is it ok.. because only crossover tables for a long number of years were some tables by subwoofer guys and stereo companies, which did not help a whole lot.

But, the 2017 tables actually have metric fill amounts in them, which lets me use my cable numbers from the BS 7671 as well...

there are are some interesting values for amps etc, when doing the work. At least when I get wires marked with USA markings I am not lost about are they ok..lol
i just look it up in the right tables and make sure.
 
mbrooke

mbrooke

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Location
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Adamjamma said:
Well, the difference gets wierd when all your tables are for USA wire sizes and all you have is metric wire available. Then you are questioning is it ok.. because only crossover tables for a long number of years were some tables by subwoofer guys and stereo companies, which did not help a whole lot.

But, the 2017 tables actually have metric fill amounts in them, which lets me use my cable numbers from the BS 7671 as well...

there are are some interesting values for amps etc, when doing the work. At least when I get wires marked with USA markings I am not lost about are they ok..lol
i just look it up in the right tables and make sure.
Click to expand...

Here is table that may help you in the future :)
 

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mbrooke

mbrooke

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jumper said:
Just glancing at the I don’t see any of the smaller equivalent wires as a problem given that the NEC is very conservative with ampacity. I could use that chart for metric sizing and not have a problem.

Who wrote/published/made it? Just for veracity, where did you get it?
Click to expand...



Yup- I agree. As per usual, the internet:

https://www.cablejoints.co.uk/uploa...qmm-Millimeters-Squared--Conversion-Table.pdf


Though to be honest I don't remember where I found the exact chart I uploaded, I think someone made it. However I've checked the numbers and they do align with those published by companies like General Cable.
 
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Adamjamma

Senior Member
Location
Jamaica and london
thanks. Pretty much on with one of my charts... I need to copy it back into the computer so I can share it as I listed the amps on mine as well.

Mine actually lists the type id for amps.. THHN/THHW etc, to the british wires using Southwire pages and Prymian pages for the numbers. Took a while to write up when I did it.. around fifteen years ago...because I had to request the booklets/brochures at the time since they were not online.

Now I just open my various code books up to the tables depending on the wire markings.
 
mbrooke

mbrooke

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Location
United States
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Technician
Adamjamma said:
thanks. Pretty much on with one of my charts... I need to copy it back into the computer so I can share it as I listed the amps on mine as well.

Mine actually lists the type id for amps.. THHN/THHW etc, to the british wires using Southwire pages and Prymian pages for the numbers. Took a while to write up when I did it.. around fifteen years ago...because I had to request the booklets/brochures at the time since they were not online.

Now I just open my various code books up to the tables depending on the wire markings.
Click to expand...



Welcome. If you make or have anything, don't hesitate to share it ;)
 
Jraef

Jraef

Moderator, OTD
Staff member
Location
San Francisco Bay Area, CA, USA
Occupation
Electrical Engineer
Back in the day when a 15A receptacle was only rated for 15A, you needed the breaker for that reason too. It’s a relatively recent development that 15A devices can be used on a 20A circuit.
 
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Adamjamma

Senior Member
Location
Jamaica and london
just as a difference to stuff.. maybe it is because all the plugs here have fuses in them, not sure, but... in the class books they say that the 13 amp outlets here have to be rated for actual 32 amps at least due to the fault that occurs if the ring main separates. Also see 45 amp outlet switches here for the cookers that have the 13 amp outlet in same unit.. and from what I have seen, only the 45 amp cables go to it. So it is a 13 amp tap, in one assembly. But most outlets here are switched, usually with a double pole switch.

One difference between UK and USA.
 
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