Beiträge von herkkop

Yep, watching the web UI / app / mqqt messages...

Unfortunately, I don't have an oscilloscope.

How do you feel about powering the Uni with DC from a bridge rectifier?

Hi,

could this work if I make a bridge rectifier and power the Uni from that?

With a large enough capacitor it should keep the voltage stable for the duration of the button push..?

But can I measure AC if powering with DC?

Hi,

I measured uni power when pressing the button. Voltage drops from 13.5 -> ~12V with a short press and when pressing long it drops to 9 volts.

The light on the Uni is not blinking so I don't think it reboots.

Transformer cables come to the doorbell and there I take the power to Uni.

Then I disconnected doorbell 1 from the transformer and connected that to the button wire.

Hi,

in the mean time I rewired the doorbell. But without luck.

Näyttökuva 2021-9-16 kello 16.06.14.png

So it's wired now like in the left image.

Now I have 0V when the button is not pressed. And it goes to 4-5V when pressed.

But still nothing in Uni. I'm wondering maybe there are some issues with it since input 1 is high even now when there is 0V to input 1...

By the way, did I already thanked you for this great help?

THANKS!

Hi,

when pushing the button it reads about 0.3 ohms... and infinite when not pushing.

And I'm still getting a reading of 13,5V between OF and T3

Hi,

the measured voltage is around 13.5V AC between terminals 1 and T3, but also between OF and T3...

And with a short, normal press of the button, it goes to about 4-5V between OF and T3. If I press the button for a longer time voltage goes to near zero.

Anyway, the Uni does not react to these voltage changes...

Hi,

here is the drawing.

The button is not illuminated.

uni doorbell.diode.png

Hi,

thanks for your suggestions thgoebel.

Unfortunately, neither of them worked. Since the voltage (measured ~13,5V AC) is constant in OF of doorbell and push-button pulls this down to 4-6V diode had no effect. When inserting the diode constant voltage to Uni's pin 7 lowered to about 10V and ringing the bell to about 3-4V.

Changing the inputs of Uni had no effect.

I have set up the button as "Detached switch" (tried also "Momentary") and "Reverse inputs" is selected as otherwise button shows always on.

Correct if I'm wrong but Uni should detect the voltage change from 13V AC -> 5V ?

Thanks again!

Hi,

I need some help trying to make my old doorbell smarter.

My goal is to leave the doorbell working as it is now and not use Uni's outputs, but detect the doorbell button push and send MQTT message when that happens.

The doorbell is Friedland type 4, and it's powered by a 12V AC transformer.

The transformer is wired so that the doorbell always has 12V AC power. Also, the button connection (OF) has a constant 12V. When the doorbell button is pushed, that 12V goes down to about 3-4V and this change is what I'm trying to detect.

The Uni is wired to ACC to T3 and N to 1. Uni's 7 is wired to OF.

Uni is powered and working ok, but it's not detecting the button being pushed.

Uni's manual says that AC below 12V is (0) low.

uni doorbell.drawio(1).png

Here is an image of the wiring.

I would really appreciate any help or ideas!

Thanks!