Voltage and Amps rating for Doorbell Transformer

Thread Starter

biferi

Joined Apr 14, 2017
390
I do not know if anybody can help but I wanted to Ask about Doorbell Transformers?
Any Home Built in the 90's and Earlier what was the Voltage and Amps that the Doorbell Transformer put out?
 

DickCappels

Joined Aug 21, 2008
10,152
The doorbell in the house I had build in Arizona in about 1999 was 24VAC did not have a chance to note the current capabilities.

Just to add, the house I had built in S.E. Asia in 2006 has a 240 VAC doorbell.
 

DickCappels

Joined Aug 21, 2008
10,152
Wait - it gets better. When the underground wires to the doorbell button started shorting together (the electrician who worked on the house really poor work-he was angry with the contractor) the new electrician used one of the wires and returned the doorbell button through earth ground. Imagine how the earthworms felt every time somebody rang the bell!
 

Sensacell

Joined Jun 19, 2012
3,432
Haha My doorbell is also 230 VAC 50 Hz. "Thailand land of smiles - and electric shocks"

When it stopped working and I went looking to fix it, I was horrified when I poked my meter on the switch terminals to find MAINS VOLTAGE -- yikes!!!
The buzzer was dead, I wired an old 5V switching wall-wart in and connected a Sonalet beeper to it.

The fringe benefit is that it produces beeps with a fixed minimum duration, the first hit charges the internal caps and it beeps until they discharge.
 

Thread Starter

biferi

Joined Apr 14, 2017
390
I am sorry I should Told everybody I am in the USA.
So if a House is Built in the 1990's and Earlier will the Doorbell Transformer be Rated 9. Volts at 1. Amp or what would it be?
 

MaxHeadRoom

Joined Jul 18, 2013
28,619
If it is the type that uses solenoids of any kind, they are pretty voltage tolerant, also they are only energized momentarily, anything in and around 9v -12v should suffice.
Post the type and construction.
Max.
 

Thread Starter

biferi

Joined Apr 14, 2017
390
I know a Standard Doorbell in the 1990's and Before uses arond 9. Volts 2. Amps.
I wanted to know what the Standard Doorbell Transformer OutPut Voltage and Amps are for the 1990's and Before?

I did not need the Voltage and Amps for the Doorbells.
 

djsfantasi

Joined Apr 11, 2010
9,156
I did not need the Voltage and Amps for the Doorbells.
Why do you think you did not need the doorbell voltage and amp ratings? You have to match the transformer voltage to the doorbell voltage rating. Plus, the transformer amp rating must exceed the doorbell requirement.

So if you have the doorbell ratings, you have the transformer rating.
 

Thread Starter

biferi

Joined Apr 14, 2017
390
I am not Replacing any Doorbells I just wanted to know.

Because most Basic House Circuits are 120 Volts 15 Amps.
Now this would be to High for Say a Ring Doorbell.
Ring Doorbells are Rated 16 Volts 20 Amps.

This is why the Doorbell Circuit has a Transformer to Supply the Right Voltage and Amps to the Doorbell.

But over the Years things change with Power Needs and so on.

So if you did come across a House Built in the 1990's and Before what would the Doorbell Transformer Voltage and Amps Output Be?
And if the House was Built in the 2,000's what would the Doorbell Transformer Voltage and Amps Output Be?
 

MaxHeadRoom

Joined Jul 18, 2013
28,619
Door bells have not really changed much over the years, pretty much use the same principle of one or two solenoid coils, the load on the transformer is usually very momentary so accurate sizing is not really a big concern, within reason.
Max.

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djsfantasi

Joined Apr 11, 2010
9,156
I am not Replacing any Doorbells I just wanted to know.

Because most Basic House Circuits are 120 Volts 15 Amps.
Now this would be to High for Say a Ring Doorbell.
Ring Doorbells are Rated 16 Volts 20 Amps.

This is why the Doorbell Circuit has a Transformer to Supply the Right Voltage and Amps to the Doorbell.

But over the Years things change with Power Needs and so on.

So if you did come across a House Built in the 1990's and Before what would the Doorbell Transformer Voltage and Amps Output Be?
And if the House was Built in the 2,000's what would the Doorbell Transformer Voltage and Amps Output Be?
First, it appears that you are confused about ampere ratings. Amp ratings of a power SOURCE are the maximum amperes that it can supply. A 120VAC 15A does NOT supply 15A to the load. It can supply UP TO 15A, but the LOAD ampere requirement is what determines the amps in a circuit. Approximately, a 40W bulb pulls 330mA; not 15A.
 

killivolt

Joined Jan 10, 2010
835
Here in Utah, we typically have 24vac system for Doorbells, I know this because I have helped people many times when their wiring grounded and blew the Trainee.

Also, most Doorbell Cameras such as Vivint Doorbell Camera Pro which is installed in all of North America, South America, and U.S. requirements are 12-24vac, makes sense if you have a run exceeding X Feet to get proper amperage and voltage e.g. same as a Furnace which I have more experience, I could be wrong about
N-S America they may have other provisions in that application.

kv
 

Thread Starter

biferi

Joined Apr 14, 2017
390
Well I Live in the USA like I Say and I am in a TownHouse.
And Yes I do know that even if I have a 15 Amp. Circuit the Device that is Pluged into the OutLet is not using 15 Amps.

But would I not be Right that the Circuit Supplying Voltage to the Dorbell Transformer is 120 VAC?
 

Thread Starter

biferi

Joined Apr 14, 2017
390
Ok now we are thinking on the same pasth.

So if the Standard Circuit of 120 Volts is going to the Doorbell Transformer what do you think it will be Stepping the Voltage Down to?
 
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