I am getting ready to change out the doorbell transformer. It is in the garage. Is there something like a "standard" circuit that is likely on to I can turn it off? How do I make sure I have it turned off before I play with it?
Have someone ring the bell and start flipping circuit breakers until it stops.
The transformer is dead. The bell ain't ringing.
Then get a tester similar to this:
How have you determined the transformer is bad? Used a meter on the primary and secondary windings? If you have no meter, you can identify the voltage on the primary with the 'barefoot wet finger' [1] approach. Then try the breakers until there's no voltage on the primary winding of the transformer.
[1] While standing barefoot, wet a finger and touch a wire. the secondary low voltage will produce a hair-raising shock and perhaps sexual arousal. touching the high voltage primary wiring will blow snot out of your nose, wax out of your ears, and lint from your navel.
Measure the secondary voltage with an ac meter. The secondary usually is terminated at two screws on the side of the transformer. If you measure between 15 and 30 volts ac there the transformer is probably NOT bad and something else is keeping your doorbell from working.
But, if there's voltage there and you still want to kill the 120 volt circuit feeding it, then just flip breakers off until that low voltage goes away.
If you don't have a voltmeter and are not willing to invest less than ten bucks for a usable one, then just forget about the doorbell and put a door knocker on your front door.
Then, sit around and hope you get a call from the Nobel Prize Comittee.
Jeff
I will, but when I just went up on a ladder to see if there were any numbers, it was hot to the touch. I am thinking that alone is a problem. Thanks for the tips on how make sure I don't BBQ myself.
So how about if there is no low voltage. What would plan B be for making sure I have cut off power.
Kurt,
Very good when jmagerl said to shut the main off this will insure you got it dead and take a flash light with you, and just a hint don't just buy the transformer since what I have found is that 8 out of 10 times the problem is that the button got stuck down and burned not just the trans but the chime itself and since Home Depot sells this in a pack that costs like $2 more if that why not change it all out including the button that probably started this in the first place.
-Lucas Lucas Electric, LLC
If I had six hours to chop down a tree, I'd spend the first four hours sharpening the axe. - Abe Lincoln
Kurt,
Very good when jmagerl said to shut the main off this will insure you got it dead and take a flash light with you, and just a hint don't just buy the transformer since what I have found is that 8 out of 10 times the problem is that the button got stuck down and burned not just the trans but the chime itself and since Home Depot sells this in a pack that costs like $2 more if that why not change it all out including the button that probably started this in the first place.
-Lucas Lucas Electric, LLC
If I had six hours to chop down a tree, I'd spend the first four hours sharpening the axe. - Abe Lincoln
Kurt,
Very good when jmagerl said to shut the main off this will insure you got it dead and take a flash light with you, and just a hint don't just buy the transformer since what I have found is that 8 out of 10 times the problem is that the button got stuck down and burned not just the trans but the chime itself and since Home Depot sells this in a pack that costs like $2 more if that why not change it all out including the button that probably started this in the first place.
-Lucas Lucas Electric, LLC
If I had six hours to chop down a tree, I'd spend the first four hours sharpening the axe. - Abe Lincoln
I'll try and give you the safest ways I can think of to avoid your exposing yourself to hazardous voltages.
*****Touch the transformer body and see if it feels like it's at room temperature or if it's slightly warmer that that.
If it's not slightly warmer than room temperature, then likely there's no power getting to it or the primary winding is open; Skip to "A" below
If it's warm, then there's power being supplied to it energizing the primary. If so, hold a piece of thin steel (like a nail file) against it as see if you can feel a slight humming vibration in that metal caused by the ac magnetic field leakage from the transformer. If you can, then start flipping breakers off until the vibration goes away and you will have found the breaker for the circuit feeding the transformer. (To be certain, leave that breaker off, wait a couple of hours, and see if the warmth you felt is no longer there.)
A. There's still two ways to go:
HTH,
Jeff
Kurt,
Very good when jmagerl said to shut the main off this will insure you got it dead and take a flash light with you, and just a hint don't just buy the transformer since what I have found is that 8 out of 10 times the problem is that the button got stuck down and burned not just the trans but the chime itself and since Home Depot sells this in a pack that costs like $2 more if that why not change it all out including the button that probably started this in the first place.
-Lucas Lucas Electric, LLC
If I had six hours to chop down a tree, I'd spend the first four hours sharpening the axe. - Abe Lincoln
ooops
Hold the nail file against what? BTW: It is very warm to the touch. Thanks for the help.
>
Just hold it very lightly gainst the flat rectangular portion of the transformer and see if you can feel a slight "buzzing" vibration caused by the alternating magnetic field. If you can, then you're in good shape to feel it stop when you switch off the correct breaker.
Just make sure it's a steel nail file and not an "emery board".
You might also be able to feel similar vibration if you hold a small magnet right next to the transformer.
HTH,
Jeff
Grab a small magnet and hold it close to the transformer, you should feel it vibrating. If so then have someone hit each breaker until the vibration goes away.
You don't have to have it turned off. Use insulated tools and - if you're scared to death - rubber gloves. Nine times out of ten, you'll be okay.
MP, you and I may be on track to becoming what they used to call Laurel and Hardy....."Two minds without a single thought".
Jeff
LOL
HomeOwnersHub website is not affiliated with any of the manufacturers or service providers discussed here. All logos and trade names are the property of their respective owners.