Doorbell and chime wiring

[jeromedawg]

Hey guys,

So I am in the process of testing out a Ring Pro doorbell over the existing Ring doorbell we have installed. The installation is a lot more involved this time around. Anyway, the chime unit from the preexisting legacy doorbell installation has the terminals "1", "2" and "T" on it. I'm assuming "T" is for Transformer and "1" and "2" would probably map to "Front" and "Rear" - does it really matter what the wiring is hooked up to if I just have one doorbell? Currently, the wiring is white on "2" and red on "T"

The other concern is that I don't know what voltage the transformer is (nor exactly where it's located). They recommend 16v-24v but people with 16v have reported issues. I don't want to deal with the hassle of replacing one of those if I don't have to - there are a couple transformers in the jacket closet near the front door but I have no idea why there are two (maybe one for the doorbell and one for a PIR motion sensor on the opposing side of the wall?) - regardless, I can't even tell which one would be for what...

[sokoloff]

I would start by looking at your electric service (circuit breaker) panel. Doorbell transformers are commonly hooked up there.

If not there, it's easy enough to unhook one of the transformers [one wire disconnect is enough] and test the doorbell. If it still works, it's not that transformer... :) Once you find the transformer, put a meter on it (set to "AC volts") to measure the voltage.

Doorbell chimes with three terminals typically have a different chime pattern for front and rear door. Front door is usually the double chime and rear a single chime. That's the only thing that matters between 1 and 2. You can try it both ways and see which you prefer.

[paddedhat]

I would recommend disconnecting any transformers that are no longer being used. They draw power as phantom loads, and they are a possible, if slight risk as a source of an electrical fire. At this point you should have two tools in your tool box. A multi-meter that you can use to read the output of your transformers, and a non-contact tester. This is a pen like device that you can use on the outside jacket of a wire to see if it is carrying voltage. Your wiring guess is correct, 1 and 2 are for front and back doors, and the "T" is the hot output of the transformer. Transformers are typically labeled, or stamped, with their output voltage. It may take a flashlight and a dust rag, but you should be able to read it. As for the hassle of changing one, once you have the power turned off, it takes five minutes to change one, and it's an easy job. Good luck.

[sokoloff]

Your other transformers might be for HVAC systems, so make sure to check that before simply removing them. I agree no reason to run a useless transformer, but there's also no reason to install a useless transformer, so it was probably useful at some point in the house's past.

[jeromedawg]

So I took a pic of what I think might be the transformers for the doorbell and inside PIR motion detector. Will have to try checking the voltage and determining which, if either, are connected to the doorbell. From what it sounds like though, I absolutely need to have a transformer in between the doorbell and chime unit?

The pictures show two terminals, one (white) with "5VA" printed and the other (red) with "10VA" printed

Other printing (on the metal) at least for one seems to read "CLASS 2 LR54224"

Actually, I just found it here... I'm pretty sure this is the same transformer (2 of which) that are in the jacket closet: http://www.ebay.com/itm/TRANSFORMER-NUTONE-SCOVILL-5-10-VOLT-TRANSFORMER-58-M1-/281056421797?_ul=EC&nma=true&si=Nu%252BbpwiDtnmpE5X26pnxhYvM5Mw%253D&orig_cvip=true&rt=nc&_trksid=p2047675.l2557

[jeromedawg]

BTW: sorry for the pic - it's rotated sideways. So the transformer on the left should be the one on top and the one on the right should be the one on the bottom.

Weird, so I'm trying to use process of elimination by flipping the breaker and unhooking the wires on each transformer. I unhooked the top (left) transformer first and I couldn't figure out *what* that's actually powering - the PIR motion sensor on the other side of the wall facing the living room is still working despite having done that! After unhooking the bottom (right) transformer though, the power to the chime definitely cut out. So I can say with certainty that the bottom (right) transformer is at least powering the chime. Any ideas what the top (left) one would be for? Since someone mention HVAC, I tried turning on the house fan and also ran cooling and heating but it all works still.

[Spork]

Do you by chance have access to a toner?  (If you know anyone that works in IT... they might just have one.  Also called Fox & hound.)  If you can power off the unknown transformer and hook the tone generator to it, you might be able to follow it inside the wall with a toner.  This is my goto method of tracking wires in walls.

[jeromedawg]

Do you by chance have access to a toner?  (If you know anyone that works in IT... they might just have one.  Also called Fox & hound.)  If you can power off the unknown transformer and hook the tone generator to it, you might be able to follow it inside the wall with a toner.  This is my goto method of tracking wires in walls.

Hmm, never heard of that tool, so I think it's safe to assume I don't lol. I'll look into it though.

[jeromedawg]

I've determined the left-hand/top transformer is controlling a fixture outside on our porch that lights up our unit number! Uh, shouldn't the HOA be responsible for powering that?! Grrr.... I wonder what the power draw is of that - I'm almost tempted to unhook the wiring and cap it all off LOL

[Spork]

Do you by chance have access to a toner?  (If you know anyone that works in IT... they might just have one.  Also called Fox & hound.)  If you can power off the unknown transformer and hook the tone generator to it, you might be able to follow it inside the wall with a toner.  This is my goto method of tracking wires in walls.

Hmm, never heard of that tool, so I think it's safe to assume I don't lol. I'll look into it though.

It looks like you've solved it... but just for explanation, it's this:
https://www.amazon.com/Cable-Tracer-Tester-Generator-Signal/dp/B001MB759U

I'm not endorsing that particular brand... I randomly found it on amazon for an example.  If you have a wire bundle of 48 ethernet cables, it makes it possible to find the ONE you are looking for.  But it also is a fine tool for finding wires in walls/ceilings/etc.

[jeromedawg]

Do you by chance have access to a toner?  (If you know anyone that works in IT... they might just have one.  Also called Fox & hound.)  If you can power off the unknown transformer and hook the tone generator to it, you might be able to follow it inside the wall with a toner.  This is my goto method of tracking wires in walls.

Hmm, never heard of that tool, so I think it's safe to assume I don't lol. I'll look into it though.

It looks like you've solved it... but just for explanation, it's this:
https://www.amazon.com/Cable-Tracer-Tester-Generator-Signal/dp/B001MB759U

I'm not endorsing that particular brand... I randomly found it on amazon for an example.  If you have a wire bundle of 48 ethernet cables, it makes it possible to find the ONE you are looking for.  But it also is a fine tool for finding wires in walls/ceilings/etc.

Now that I see what it is, I probably have seen one of those but it was probably a long time ago. Pretty cool though - maybe some day I'll pick one up. I don't do enough wiring/electrical work as it is to justify it though. Plus, I'm not in a *huge* place with tons of wiring to run currently.