Trying to replace my doorbell transformer

l69norm wrote: ↑no photo

pfc456 wrote: ↑ Sorry thought I included it. Attached here.

l69norm wrote: ↑ Green goes to the grounding bar on the far left were all the bare ground wires are connected to

The metal case of the transformer is mechanically tied to the breaker panel case/ ground

thriftshopper wrote: ↑ Get a continuity tester just to be sure if you want but the bar on the left should be thd ground bar. If the incoming wires with ground have their ground wires attached there (appears to), then it is where to ground to.

pfc456 wrote: ↑ Thanks. I'm sharing another photo below - it looks like I have two grounding bars (one on the left and one on the right). Is that normal?

Out of curiosity, what's the most dangerous thing that can happen if I install the grounding wire incorrectly (i.e. if that bar is actually a neutral bar, or if the bar on the far left isn't actually a grounding bar)?

Is turning off the breaker for the live wire connected to my doorbell sufficient or do I need to turn off the power for my entire house (might be a stupid question but just want to make sure).

pfc456 wrote: ↑ Thanks. I'm sharing another photo below - it looks like I have two grounding bars (one on the left and one on the right). Is that normal?

Out of curiosity, what's the most dangerous thing that can happen if I install the grounding wire incorrectly (i.e. if that bar is actually a neutral bar, or if the bar on the far left isn't actually a grounding bar)?

Is turning off the breaker for the live wire connected to my doorbell sufficient or do I need to turn off the power for my entire house (might be a stupid question but just want to make sure).

TomLafinsky wrote: ↑ Yes you have two ground bars, one for each leg (side). If you have never worked in an electric panel I would strongly suggest you turn off the main (house) breaker. Your safety is what matters the most. Make sure to have a flashlight before turning off the main, it's dark out there without power

CNeufeld wrote: ↑ Jebus, dude! Unless you know what the heck you're doing, you should NEVER muck around in the panel without the power turned off! One slipped screwdriver and you're in for a world of hurt. If you're lucky.

C

pfc456 wrote: ↑ Thank you all for the feedback. I will definitely turn off the main power for the breaker! I'll validate that all wires that I can touch are off with a voltmeter before attempting anything.

For this one particular switch, it looks like it's powering my doorbell + something else in my house (hence the two black wires connected to the same screw). Is there any concern switching to a more powerful transformer may be too much load for this switch? I presume that the breaker would trigger in that scenario.

pfc456 wrote: ↑ Thank you all for the feedback. I will definitely turn off the main power for the breaker! I'll validate that all wires that I can touch are off with a voltmeter before attempting anything.

For this one particular switch, it looks like it's powering my doorbell + something else in my house (hence the two black wires connected to the same screw). Is there any concern switching to a more powerful transformer may be too much load for this switch? I presume that the breaker would trigger in that scenario.

CNeufeld wrote: ↑ .
Do you have two wires coming off the transformer, going to two different locations? Do you have a front and back doorbell? Or are you talking about the two wires coming off the one breaker? Maybe one of the electricians in this forum can comment on whether that's acceptable from a code perspective.
.

CNeufeld wrote: ↑ Anything is possible, but not likely with just a transformer change. And yes, the breaker would trip in that case.

Do you have two wires coming off the transformer, going to two different locations? Do you have a front and back doorbell? Or are you talking about the two wires coming off the one breaker? Maybe one of the electricians in this forum can comment on whether that's acceptable from a code perspective.

C

l69norm wrote: ↑ Technically, no - you are not allowed to double tap from 1 breaker unless the breaker was designed to accommodate this

it's a lot harder to get the right pressure on the connection so that it won't come loose

pfc456 wrote: ↑ I'm swapping a really old 5VAC transformer in exchange for a 16VAC-10VA transformer so I can use my Ring Video Doorbell Pro. I've also seen silver-coloured wires connected to the ground bar. Out of curiosity what kind of wires are these? Since my house was built in the 70s, could it be aluminum wiring?

l69norm wrote: ↑ Technically, no - you are not allowed to double tap from 1 breaker unless the breaker was designed to accommodate this



it's a lot harder to get the right pressure on the connection in a double tap so that it won't come loose

pfc456 wrote: ↑ Gotcha, so whoever previously did the work may have done it incorrectly. If I move forward with replacing the transformer can I tighten the screw and pull on both black wires to verify they can't easily come loose?

TomLafinsky wrote: ↑ Yes after switching off the main breaker you can 'play' with the wires. If the two wires are next to each other in the same hole it is a somewhat better fit than one on top of the other. Anyway screw hard enough and nothing will move.

pfc456 wrote: ↑ Thank you so much! So I'll go through these order of steps this weekend:

1) Turn off main power
2) Verify no power in any of the black wires in my breaker box with my voltmeter
3) Unscrew the screws holding onto the black/white wire for the old transformer, remove old transformer
4) Connect white/black wire of my new doorbell transformer to the same connections as the old transformer, tighten screws. Tug on each wire to make sure they're secure
5) Connect the green wire to the ground bar on the top left (any of the unused holes should do?). Tighten screw to secure the wire. Tug on the green wire to ensure it's secure.
6) Turn the main power switch to the breaker back on. Verify everything works as expected and existing doorbell still works
7) Replace old doorbell with my Ring Video Doorbell Pro