Metal Box and Doorbell Trans. Question
#1
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Metal Box and Doorbell Trans. Question
Hi-
I mounted a new doorbell transformer today. Its a Heath Zenith brand. It has a plastic screw/locknut that mounts to a 1/2" knockout. I mounted it to a blank 4" cover with the knockout hole in center.
However, I have all metal conduit which serves as my ground. Was this the wrong transformer (ie plastic mount) for this application? I fear its against code to have this plastic locknut business inside a metal box.
The old transformer didnt have a ground wire, new one did which I made a connection with the box.
But I wonder, if instead I had just capped the green, would I still have been grounded?
If a portion of the metal of the transformer was in contact with the cover its mounted on then I should be grounded? Unless of course I bought the wrong tranny, perhaps for a plastic box or something?
Heath Zenith Wired Door Chime Transformer-121AC-A at The Home Depot
How can I test this for ground without having to take the box apart?
I mounted a new doorbell transformer today. Its a Heath Zenith brand. It has a plastic screw/locknut that mounts to a 1/2" knockout. I mounted it to a blank 4" cover with the knockout hole in center.
However, I have all metal conduit which serves as my ground. Was this the wrong transformer (ie plastic mount) for this application? I fear its against code to have this plastic locknut business inside a metal box.
The old transformer didnt have a ground wire, new one did which I made a connection with the box.
But I wonder, if instead I had just capped the green, would I still have been grounded?
If a portion of the metal of the transformer was in contact with the cover its mounted on then I should be grounded? Unless of course I bought the wrong tranny, perhaps for a plastic box or something?
Heath Zenith Wired Door Chime Transformer-121AC-A at The Home Depot
How can I test this for ground without having to take the box apart?
#2
Welcome to the forums.
That's all you need to do. It doesn't matter that the transformer had a plastic connection.... it is grounded thru the green wire. So a ground screw in the back of the metal junction box is ideal.
The old transformer didn't have a ground wire, new one did which I made a connection with the box.
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Hi thanks for your reply.
Are you sure the transformer isnt for a plastic box since it has a plastic lock nut and a ground wire?
I just want to make sure its code compliant to have plastic inside a metal box.
Is it OK to have the transformer on the load side of a gfci?
Are you sure the transformer isnt for a plastic box since it has a plastic lock nut and a ground wire?
I just want to make sure its code compliant to have plastic inside a metal box.
Is it OK to have the transformer on the load side of a gfci?
Last edited by ardmi; 12-02-13 at 03:42 AM.
#4
It is fine on a metal box. I'd put it on the line side so a tripped GFCI wouldn't interfere with operation but if only GFCI protected circuit available that is fine. No code question either way.