Dahua DB-11 Power / Wiring question (AC vs DC)

[24c]

Hi all,

I have just purchased a DB-11 which is unfortunately not compatible with my existing door bell (which has a 8V AC transformer in it, which I should have checked before hand). Anyway, I see in the DB-11 specs (and on the sticker on the back) it supports 16-24VAC and 12V or 24V DC power. My question is, how do you wire it up for DC operation? I cant see any polarity information on the terminals (with respect to the DC input) so am not keen to just give it a go given I also cant seem to find any other information about using DC to power it.

Is anyone able to point me in the direction of more info on using a DC power source for this doorbell?

Cheers,

 

[TonyR]

I don't have this unit, but the specs here say that the Power Supply can be 16 VAC to 24 VAC, 0.04 A or 16 VDC to 24 VDC, 0.04 A.

The reason why it can state that either AC or DC will work is because it likely has a linear, full wave bridge rectifier circuit on the input. That means it takes AC, converts it to DC (a pair of diodes for the positive cycle and a pair for the negative cycle), smooths and filters with capacitors and probably feeds it to a regulator IC ir IC's for the internal voltage(s) needed for the camera.

The good news is that you can feed DC to such an input as describe above with no regard to polarity because the DC will be routed properly just the AC would, but there would be a slight voltage drop that will be accommodated, by design, by the wide-input range of its voltage regulator circuit.

 

[24c]

The good news is that you can feed DC to such an input as describe above with no regard to polarity because the DC will be routed properly just the AC would, but there would be a slight voltage drop that will be accommodated, by design, by the wide-input range of its voltage regulator circuit.

Hey thanks for that - makes sense and gives me the confidence to give it a go - so I will

Cheers,