Cutting power to doorbell transformer

[shawnc1959]

Just bought a 1950s era home and I want to replace the old doorbell with a new camera one. I found what I believe is the doorbell transformer in the basement utility room (see photo):

Per the specs for the new doorbell, this transformer should be sufficient. But my issue is that I cannot find the circuit in the panel box that will turn off power to it so I can rewire the new doorbell. There's a cable from the box in the photo to which the transformer is attached (I assume this is where the transformer is getting its power) that goes to a light nearby, and when I turn off what I believe is the breaker for that room (the labeling in the panel box is atrocious), all the lights in that room go off, but the doorbell still rings. I've tried several circuits which should be for the basement, but I can never seem to get the one that includes that transformer because the doorbell keeps ringing.

Is it possible it's somehow on the same circuit as the doorbell chime upstairs in the hallway?

 

[Marty]

Why do you need to shut the power.? Thought the output is low voltage. Or, take wire off transformer output side.

 

[shawnc1959]

It is low voltage, but after I finally found the right circuit, it turns out I needed to replace the transformer anyway; so needed the circuit off after all.

 

[Marty]

If you are careful and experienced, you can do it with power on. I replaced mine that way and did not get shocked.

 

[Frank Lavornga]

Just bought a 1950s era home and I want to replace the old doorbell with a new camera one. I found what I believe is the doorbell transformer in the basement utility room (see photo):

View attachment 6307
Per the specs for the new doorbell, this transformer should be sufficient. But my issue is that I cannot find the circuit in the panel box that will turn off power to it so I can rewire the new doorbell. There's a cable from the box in the photo to which the transformer is attached (I assume this is where the transformer is getting its power) that goes to a light nearby, and when I turn off what I believe is the breaker for that room (the labeling in the panel box is atrocious), all the lights in that room go off, but the doorbell still rings. I've tried several circuits which should be for the basement, but I can never seem to get the one that includes that transformer because the doorbell keeps ringing.

Is it possible it's somehow on the same circuit as the doorbell chime upstairs in the hallway?

Yes

 

[shawnc1959]

If you are careful and experienced, you can do it with power on. I replaced mine that way and did not get shocked.

When it comes to doing anything electrical, I lean towards uber cautious. But it was a useful issue because it prodded me to go through every circuit in the panel, and create a detailed spreadsheet of every outlet, switch and appliance on each one. Which revealed some very strange wiring decisions made during the various renovations made on this house over the last nearly 70 years.

 

[Marty]

I too made two lists. One says what each breaker controls. The other is in reverse, what breaker controls this outlet, for example.

 

[shawnc1959]

I too made two lists. One says what each breaker controls. The other is in reverse, what breaker controls this outlet, for example.

Creating a list from both perspectives is a good idea. One main floor bedroom has six outlets with three on one wall; of those three, the two on the ends are on a different breaker along with outlets/lights in the basement that were added during some past renovation. So I'm guessing the two bedroom outlets were added to make the room into an office at the same time as the basement work. In lieu of a 2nd spreadsheet (which I'm now going to do), I wrote the circuit numbers on the back of the outlet covers.

 

[Marty]

Excellent idea.

 

[FAAQ2]

The transformer is only about 10 - 15 volts. Most doorbells are wireless anyway.

 

[Marty]

The transformer is only about 10 - 15 volts. Most doorbells are wireless anyway.

I only install wireless when hardwired system is not working. With wireless, you are bothered with replacing batteries in pushbutton and chime (Unless it is plug-in)