Calling on electricians!

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BigJ273

Minister of Fire
Feb 15, 2015
713
Maryland
Does anyone know what this little box is/does? It’s connected to a switch box in my attic, which I believe also houses the wires for my doorbells, and outdoor lights.

41C872FA-4B9E-4ACC-9070-4048551C479C.jpeg
 
Looks like a doorbell transformer. Supplies low voltage to power the doorbell.
 
Indeed likely 24 V transformer. But then there should be a second set of wires attached (a 110 V set and a 24 V set).
 
I see 4 wires in the pic. The larger black and white wires are 120vac and really ought to be in a conduit.
 
You are right; missed them.
 
Got it. Second question…these wires run into a junction box, where the bigger white and black wires (120) are connected with wire nuts. Also in the same box are all of the doorbell wires, also connected together with wire nuts (red and white). Can these low voltage wires be in the same box as the 120? I’ve seen mixed info
 
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Just superfluous, pls switch off the breaker first, and check (measure) that the wires are safe to handle before you do something.
 
Just superfluous, pls switch off the breaker first, and check (measure) that the wires are safe to handle before you do something.
I turned the entire panel off. Doorbells can be tricky to locate sine they usually are not on their own breaker. Apparently.
 
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I like to use wiring strips with shorting bars to common all the screws, for doorbells and thermostats. It allows you to hang identification tags off each cable, once you've identified where they go, for easier debug later.

Mount a pair of these next to the transformer, outside the breaker box, for the low-voltage wiring. If the wires are too long, don't cut them back, you may need the extra length later. Instead, use the pencil corkscrew trick.

Amazon product ASIN B07CLY91HZ
 
mount the transformer to a metal 4 inch square. then attach the feed wires from the 120 volt feed to the wires that come out of the hole that has the bigger blue and white. use the nut that is already on the threads. the screws on the outside of that transformer is where the wiring for the doorbell itself is wired and the doorbell is 16 volts not 24. if you hookup a 24 volt transformer to a doorbell it's only a matter of time before the doorbell gets blown. and wires for the 120 volt system should not be in the same box as the 16 volt wires
 
also buy a 4 inch blank cover for the 4 inch metal box that the transformer is mounted to
 
Hm, I've always had 24 V door bells. I see 16 V also exists..so it can be both.
 
Thanks for all the replies. At the end of the day, I realized we never cared about the doorbell anyway, so I completely disconnected it. Problem solved!
 
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Thanks for all the replies. At the end of the day, I realized we never cared about the doorbell anyway, so I completely disconnected it. Problem solved!
Well, maybe not.
How did you disconnect it? If you left the two 24v wires not connected just dangling? You should at a minimum terminate them in a covered box with wirenuts on each. Wires that appear benign just bare and exposed, but far from anything can suddenly get pushed into something by a rodent causing arcing/sparks and possibly a fire.
Also as someone pointed out, you should remove the door bell wires from the high voltage box. They should never be combined. It would be easy for a DIY to make a mistake and wire two together from the same box.
 
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Hm, I've always had 24 V door bells. I see 16 V also exists..so it can be both.
should say right on the inside of the doorbell i've been doing electrical since the mid 80's and have never seen one 24 volt. i've have seen 1.5 volt dc systems that ran on a battery but they were very very old and were the original electrified doorbell system
 
Well, maybe not.
How did you disconnect it? If you left the two 24v wires not connected just dangling? You should at a minimum terminate them in a covered box with wirenuts on each. Wires that appear benign just bare and exposed, but far from anything can suddenly get pushed into something by a rodent causing arcing/sparks and possibly a fire.
Also as someone pointed out, you should remove the door bell wires from the high voltage box. They should never be combined. It would be easy for a DIY to make a mistake and wire two together from the same box.
The high voltage, and low voltage wires were each capped, taped, and placed into separate boxes
 
should say right on the inside of the doorbell i've been doing electrical since the mid 80's and have never seen one 24 volt. i've have seen 1.5 volt dc systems that ran on a battery but they were very very old and were the original electrified doorbell system
Yes. 4 homes, two in the US, two in Europe. Each 24 V.

Doesn't matter tho; neither 16 nor 24 belongs in a line voltage box.
 
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Hm, I've always had 24 V door bells. I see 16 V also exists..so it can be both.
My house built in the 1950s is 16 VAC. I use a bridge rectifier to power other home made circuits with DC and hold lights for my phone system since it's always on. The doorbell is the original plunger type.
 
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I don't know what the issue is. I always had 24 V bells, so that's what I noted. I never said 16 V bells is not possible.
24 V may be rare - but I have never had something else.

It's not the point of this thread.
 
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