Using Existing Door Sensors of Alarm

I currently have a DSC alarm system that has wired door sensors.
I have some z-wave door sensors that allow for an external input.
I would like to be able to get notifications of my doors and windows being opened via Smart Things.
I wanted to see if there is a way to use my z-wave door sensors along with my existing DSC alarm setup.

You posted the same/similar question back in January, and @geko sent along a link to a real good solution. Have you tried searching the Community:

Here’s one that may beold, but it’s still relatively active:

I did do a search before posting.
Unfortunately, the approaches that I see being presented are to add a another device (e.g., DSC IT-100, Envisalink EVL-3, etc). Others totally remove the DSC alarm from the picture.
I want to use the existing alarm, but I want to hook up my sensors so they can piggy back off of the current DSC system.
I am trying to see if I can get away without doing this given I have a number of sensors that allow for an external input.
I did a serach for geko’s posts again and could not find the one you might be referring to that might solve my problem the way I am trying to. I did find the following: “Do not connect your sensor to the panel’s output. The sensor’s auxiliary input is meant only for non-energized contacts, like reed switches. Panel’s output is typically 12V and will likely damage your sensor. You need to galvanically isolate the sensor from the panel using either relay or optocoupler.”

However, there was an ask of how to use the optocoupler, but no reply back. I am hoping someone can shed some more light on the topic.

Search for Alarm Decoder. It’s basically a device that acts as another keypad on your alarm panel. There are several projects on the community that leverage them including the envisalink.

There’re multiple ways to connect a wired alarm panel to SmartThings, but all of them involve “another device” of some sort. You can’t just connect (or “piggyback” Z-Wave sensors to the alarm panel (not safely, anyway).

The simplest way I’m aware of is what this guy did:

hello i have a multi sensor it pops up and tells me that the door is open how to a make my phone sound an alarm