hey!just opened up an eletrical box to replace the switch and found a 15 amp switch.i looked at the wire and it is 12 gauge.went back to the main panel and found out it was a 20 amp circuit.i thought on a 20 amp circuit you use a 20 amp switch.where did i go wrong on my thinking?jvl
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No.
Siwtches need to be matched to the load. So unless you are switch a LOT of BIG LIGHTS you don't need a 20 amp siwtch.
However, all of the wiring on a 20 amp circuit needs to be at least #12.
My guess the reason for the difference is if you every change the lighting that it would be easy to change the switch. But not near as easy to change the wiring.
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A-holes. Hey every group has to have one. And I have been elected to be the one. I should make that my tagline.
If it was a 20 amp switch in on a 15 amp circuit then you might have some cause for concern :)
Handyman, painter, wood floor refinisher, property maintenance in Tulsa, OK
Why?
'Cause you'd know the switch wasn't installed by a pro--I've never met an electrician who would spend extra $$$ on a 20 amp switch if it wasn't necessary.
Like everyone else has said - don't worry about it. Switches need to be sized for the load.
It is an oddity in the NEC which permits the use of 15A or 20A switches or duplex outlets on a 20A circuit. Your installation would pass electrical inspection, including a new construction / installation inspection.
So far as I know the only common place which absolutely requires a 20A device on a 20A circuit is a dedicated 20A circuit which only serves 1 outlet - meaning a single plug - like a dedicated line for a window air conditioner.
If you were to run a 20A line for the air conditioner and then install a duplex outlet at the one location - you could use a 15A duplex since that counts as 2 outlets. Legal but perhaps not the best in this situation.
About the only place I use 20A switches is the heater switch for a larger heater in a bathroom - set a lot of those heat / light units up with a 20A switch for the heater and a sliding dimmer for the light.
If you are really curious - check the duplex outlets over your kitchen counters - I'll bet you find #12 wire, 20A breakers, 15A duplexes or GFCIs. Same section of the code applies.
Before you get worried because the GFCIs are fed through (one GFCI protects 2 or 3 outlets "downstream") - all of the 15A GFCIs I have seen recently are rated for 20A feed through.
Jim
It will also be clearly marked on higher quality recepticles that they are rated for 15A load and 20A pass through....that's not a mistake, it's rustic
All 15 amp duplexes are rated for 20 amp pass through or total current.But I have only see the 20 amp pass through markings on GFCI's..
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A-holes. Hey every group has to have one. And I have been elected to be the one. I should make that my tagline.