[Vikemaster12!]

I have an existing 20 amp grounded circuit in my garage. It is wired with 12 gauge as it should be. I tapped into it and ran UF-B buriable cable through the proper conduit out to a lawn light that has merely a 15 amp bulb and to a small gate opener that only draws about 2.5 amps when it runs a few times a day for 30 seconds. They are about 40 ft away. I used 14 gauge wire. Since the the light and opener are not drawing much amperage will this be ok even though technically I should have used 12 gauge?

 

[CodeMatters]

Not sure what you're asking..............
Will it likely work fine forever? Yes.
Is #14 protected properly by a 20A breaker if/when something goes wrong? No
Does it meet code? No

 

[Old Thomas]

A short in the 14 gauge wire or anything downstream can make the 14 gauge wire burn before tripping the 20 amp breaker. The breaker’s primary purpose is to protect the wire. Will it be ok? I don’t know. Do you feel lucky trying to stuff 5 lbs. of sh— in a 3 lb. bag?

 

[Msradell]

To sum it up, "it's a code violation" and shouldn't be done.

 

[jreagan]

A short in the 14 gauge wire or anything downstream can make the 14 gauge wire burn before tripping the 20 amp breaker. The breaker’s primary purpose is to protect the wire. Will it be ok? I don’t know. Do you feel lucky trying to stuff 5 lbs. of sh— in a 3 lb. bag?

Burn? Unlikely. A dead short pulls much more than 20A and the 12 gauge wire doesn't "burn". An extended pull of more than 15A will cause the 14 gauge to heat up such that it could cause nearby material to burn.

 

[huesmann]

Not sure what you're asking..............
Will it likely work fine forever? Yes.
Is #14 protected properly by a 20A breaker if/when something goes wrong? No
Does it meet code? No

But it would if he replaced the 20A breaker with a 15A.

 

[Oso954]

But it would if he replaced the 20A breaker with a 15A.

No, that creates another code violation in the US. The garage receptacle circuits are required to be 20 amp

If he’s on NEC 2017, the tap off the garage receptacle circuit is a code violation. The best thing is to remove the tap. Put it on an outdoor receptacle circuit or a new circuit.

Also, I’m wondering about that 15 amp bulb (1800w) ??

 

[Old Thomas]

Burn? Unlikely. A dead short pulls much more than 20A and the 12 gauge wire doesn't "burn". An extended pull of more than 15A will cause the 14 gauge to heat up such that it could cause nearby material to burn.

So you don’t like the way I phrased it, the place still burns to the ground.
I have seen undersized wires that were shorted but not to the point of tripping the breaker. They smoke and get really black and crispy. If you want to call that something other than burning, go ahead.

 

[huesmann]

No, that creates another code violation in the US. The garage receptacle circuits are required to be 20 amp

If he’s on NEC 2017, the tap off the garage receptacle circuit is a code violation. The best thing is to remove the tap. Put it on an outdoor receptacle circuit or a new circuit.

Also, I’m wondering about that 15 amp bulb (1800w) ??

Missed the part where it was a garage. You're right, of course.

Maybe it's a garden heater? :biggrin2:

 

[SeniorSitizen]

I don't recall ever seeing a 15 amp bulb. I'm betten that's one hellofa light.

 

[surferdude2]

Say watt? :wink2:

SD2