DIN Ring transformer polarity

I’m trying to hardwire my alarm siren to the spare DIN transformer that I got with my Ring Doorbell Pro2. It has terminals 1,2 3 & 4. To provide 24volts I need to use terminals 1 and 4 but which is + and which is - as this seems to matter when wiring a siren. Its not clear from the information printed on the transformer itself.

The DIN transformer power output specifications;

24VDC, 0.42A, 10.0W
Built-in short-circuit protection.

look to be just outside of the Alarm Outdoor Siren hardwiring specs

  • Do not apply DC power above or below 9–28V, 12W
  • Do not apply AC power
  • Do not use wire gauge above or below 0.2-2.5mm2

Check out our Outdoor Siren Help Center article for more tips on installation. When it comes to wiring, we advise consulting with a qualified electrician. :slight_smile:

1 Like

I bet it’ll work fine. The polarity doesn’t matter. It’s only to power the LED light, the siren itself works from those big old Ever Readies :wink: