Video Doorbell Wired 24vDC

I’ve a transformer in my mains board supplying 24vDC. After connecting the Video Doorbell Wired, I saw nothing was happening. Hence, thinking that maybe the transformer was not supplying enough current, I went ahead and hooked up my lab bench power supply (DC again) and set it on 24V.

As you can see in the picture, the doorbell gets 24VDC which according to the back of the doorbell (and various sources) is ok and the power supply is set in constant voltage mode (the current limiter was progressively bumped up). But as you can see the doorbell remains quiet and doesn’t consume any current.

I called in and got a replacement as the agent said the unit might be faulty.

So today I got a replacement and it’s the exact same story. The only difference is that this time I heard some kind of a clic when hooking up the power supply.

To eliminate the power supply from the equation I hooked up a voltmeter to confirm the reading. Which it does.

Only explanation I have is that the unit actually doesn’t support 24VDC (which goes in opposition with the safety label on the back).