Doorbell

[TPro]

Hi all,

I bought a new transformer for my doorbell. After installing it the chime not only rings, but "buzzes" at the same time the button is pushed. The chime itself is new also and made by the same manufacturer. It calls for 16 v. I checked the voltage at the transformer and it's almost 22 volts although its a 16v transformer.

So, my questions would be, is it normal for a 16v transformer to put out 21.90 volts? Would this be the cause of the "Buzzing" noise or is the chime bad too?

Thanks, tom

[ABP]

Please waite for maybe an electrician to give a better answer, but something to think about is most doorbells now work off of electronic circuits which are very sensitive to voltage, I would tend to think if your transformer is registering higher than its rated output that it could well cause this problem.

[HayZee518]

The common step down transformer for doorbell circuits is likely 24 volt or 16 volt. If the input voltage goes up then the output also goes up at the same rate. A chime consists of a plunger within a coil of wire and a return spring. When you press the button current flows through the coil and magnetizes the core pulling it into the coil. AC current typically buzzes because it is changing polarity 120 time a second. Most chimes do not have a "shading coil" which effectively shorts out the coil's laminations so the laminations buzz. A small counter emf is generated in the coil or iron laminations of the coil form. This is called eddy currents.
Open circuit voltages are generally higher than the expected voltage output. If you measure the voltage with the circuit energized you should read close to the nameplate voltage considering the input voltage. It is not unusual to read 130 volts on a 120 volt circuit. Lamp manufacturers are aware of this and actually rate their bulbs up to 140 volts.
Electronic annunciators operate within a voltage range and their currents are in the milli-ampere range, whereas the hard core electrical ones operate in the 1-5 amp range.

[TPro]

Update:

I tried another transformer, also rated at 16v. The output is 17.5.
The chime still had the buzzing noise (in the coil? perhaps. It's behind a sealed plastic panel that would be destroyed to find out) the same time the bell was ringing.

Apparently the 5v difference dosen't matter although I would think that 2 transformers from the same box should not have a 5v output difference.

Went to HD and bought a new chime. It does the same thing.

All parts are the same manufacturer and model as what was in the system when it stopped working.

It's not the cheapest chime, nor the most expensive. I didn't buy it because of the cost, It was the sound that I thought fit the house.

Apparently, it's just cheaply made junk.