How to connect Schlage Door Sensor to Doorbell?

I really like the Schlage door sensor because of their external switch connector on their board. How would I go about connecting this to my existing powered doorbell?
Based on this guide I assume I can’t just connect the existing wiring from my house because it has a load and the external switch connector on the Schlage needs to be at 0V correct? What exactly do I need to connect so that I can continue to use my existing wired/powered doorbell the way it is but also have it be connected to the Schlage? Thanks so much!

As @cw-kid explains in his blog, you probably need to add a relay wired across the door-bell coil to give you a volt-free contact for your Schlage. That may not be too difficult provided you can get to the door-bell’s internal wiring. You would need to find the coil connections and determine the voltage across them when the button is pressed.

If you need help locating the connections, post some clear photos of the internals.

Thank You for posting so quickly Rex. My electronic days are a bit rusty so let me take some pictures and post them tonight. So before I test the voltage on the doorbell I assume its between 8-24 volts coming to the coils? Will the relay switch on and off based on that voltage and then on one of the pins of the relay this will give me the 0v that I will connect to the Schlage? If you can help explain it better that would be most helpful.

A relay is a switch that is operated by the magnetic field from a small coil. The switch is electrically isolated from the coil so provides the volt-free (aka 0v or dry) contact on a pair of terminals that can be connected to your sensor.

Relays come in many sizes. You will want a miniature or sub-miniature, low-power type with a coil operating voltage to suit your door-bell. Common ones are 6V, 12V or 24V (dc). Relays for ac are also available if necessary. The relays work over a range of voltages so it is usually a matter of picking one that is the same or slightly higher than your door-bell coil.

Seems like I recall someone having an issue with the schlage sensor and the doorbell. I think it was related to instances when a user pressed the doorbell quickly and it didn’t register. You might want look through the forum for additional info.