15A (light) switches on 20A circuits?

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olc

Senior Member
Can 15A light switches be used on 20A circuits?
(assume lighting load is less than 15A)
 

Dennis Alwon

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Can 15A light switches be used on 20A circuits?
(assume lighting load is less than 15A)

Can a 15 amp receptacle be on a 20 amp circuit-- YES also, as long as it is not a single receptacle and a separate cir. Look at Table 210.21(B)(3) and art. 210.21(B)
 

olc

Senior Member
Switch as opposed to receptacle.
Can someone point me to the relevant NEC paragraph?
 

Dennis Alwon

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Switch as opposed to receptacle.
Can someone point me to the relevant NEC paragraph?


Sorry I was backing up my statement. The point I was making was that it was compliant for receptacles so why wouldn't it be for switches.
 

olc

Senior Member
404.14 specifies the load that can be connected to the switch, not the rating (current protection) of the branch circuit that the switch is connected to. (unless I am missing something which could be the case.)
This is driving me nuts. It seems normal but I can't find anything to say it is.
Perhaps the 15A switch is listed for 20A circuits by the manufacturer?
 

infinity

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New Jersey
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404.14 specifies the load that can be connected to the switch, not the rating (current protection) of the branch circuit that the switch is connected to. (unless I am missing something which could be the case.)
This is driving me nuts. It seems normal but I can't find anything to say it is.
Perhaps the 15A switch is listed for 20A circuits by the manufacturer?


I can see your frustration but wouldn't that just be a 20 amp switch?
 

iwire

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Location
Massachusetts
404.14 specifies the load that can be connected to the switch, not the rating (current protection) of the branch circuit that the switch is connected to. (unless I am missing something which could be the case.)

I believe 404.14 covers it.
 

Dennis Alwon

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I believe 404.14 covers it.


I agree. It states that the switch shall be used within its rating. Why would it need to be rated 20 amps if you only have a 100 watt load? If the switch turned the entire circuit on that was rated 20 amp then perhaps the switch would need to be rated 20 amps but not for loads rated less than 15 amps
 

olc

Senior Member
To answer the question - Why can't a 15A switch be used if the load connected is less than 15A?:
Why can't #16 wire be used on a 20A circuit if the connected load is less than say 5 amps?
Because the NEC says so.

I think the answer to the 15A switch on a 20A circuit question is that the NEC does not say that the switch can't be used.
I was looking at older threads and that seems to be the consensus.
 

mgookin

Senior Member
Location
Fort Myers, FL
The building wiring is sized by the OCPD.
Switches, receptacles and wiring internal to a load are sized by the load they will carry.

That's why the wire you're connecting when installing a ceiling fan is so small even when on a 15A or 20A circuit.

Think of a table lamp. That may be on a 20A circuit but the cord only needs to carry the load of the lamp. The cord cap only needs to carry that same load. Same with the receptacle.

But with building wiring that has lots of loads connected in parallel, it needs to be sized for the OCPD.
 
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