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question about installation of 20 amp wall plug

I bought a replacement wall plug that is rated 20 amps. I installed it from a 15 amp circuit breaker, in the add it said it was ok to use in 15 or 20 amp. I pluged in a cheap intergraded amp to it and it and my speakers started popping and the amp started to smoke, I unplugged it right away. Was I wrong to assume that it would be ok coming from a 15 amp circuit, can anyone tell me what I did wrong, thanks
kedoades
xti16
1,525 posts
 
My guess is you miswired it. Sounds like maybe you had Hot and Ground reversed. Putting a 20amp wall plug on a 15 amp line shouldn't be a problem (you are limited to the 15 amp breaker).
krell_man
827 posts
 
You either miswired it or you have the wires touching each other. Pull the outlet back out and check it. The green wire goes to the ground screw. The white wire normally goes to the outlets on the same side as the ground wire. The black wire normally goes on the other side. Are all of the screws tightened down?
gbart
290 posts
 
You should not use a 20A receptacle on a 15A circuit, regardless of what the audio retailers say. This is not allowed by the NEC. There is the potential for longterm overloading of the 15A circuit.

A typical household circuit breaker will trip in the presence of either a bolted fault (i.e., dead short) or large overcurrent, depending on amount of that overcurrent.

The maximum continuous/longterm current draw allowed on a 15A circuit is 12A or 80%. When you install a 20A receptacle, there is the increased potential for longterm current draw to be as much as 100% to 110%, depending on the trip curve of the breaker, yet not have it trip. That is the reason for the prohibition ny the NEC.

Please see the receptacle ratings table in NEC Article 210.

http://img.villagephotos.com/p/2003-5/191557/Receptacle_Ratings_Table.jpg

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jea48
4,471 posts
 
Kedoades,

As for the 20 receptacle it did not cause your problem.

If you have a volt meter I suggest you check the voltage and polarity at the recept.

Small straight slot contact is the Hot.
"T" shaped slot is the neutral.
"U" shape hole contact the safety equipment ground.

*Hot to neutral you should read 120V nominal.
*Hot to safety equipment ground 120V nominal. (This will tell you the polarity is correct.) Reversed polarity would not have caused your problem.....
*Neutral to safety equipment ground zero.

Could be the cheap intergraded amp shot crap all on its own.....

As for NEC code though.... a 20 amp receptacle can only be installed on a 20 amp branch circuit. Two or more 15 amp rated receptacles can be installed on a 20 amp branch circuit.
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