Intercom/Door opener w/ FreePBX

First time caller but long time listener… I was able to get some great help here over the past few months.

I’m providing service to a customer using a virtually-, remotely-hosted FreePBX So far all is working well - I’m using Cisco SPA-303s.

I now need to install an intercom with a door opener. My guess is that I need a some kind of a door phone, for which I’ll run ethernet connectivity to the company’s main switch, and configure it to connect to the remote PBX after I assign a specific extension for it.

Then, after researching here, I understand that I need a DTMF-enabled intercom which, once the correct sequence is hit on the phone, will open a relay which will open the door.

Can anyone assist in suggesting popular models, as well as some basic configuration on the PBX and intercom appliance side? I guess I need to connect the relay to something called “door strikers”? Also how do I configure the PBX to send out the DTMF sequence to open the relay using a pre-defined code?

Thanks in advance for all the help!


You dial the DTMF sequence to open the door when the Intercom calls you.

The Cyberdata stuff is the gold standard, fully certified for FreePBX and supported by the C-EPM.

Cyberdata is great but if you want a video phone have a look at 2N. They work very well with Asterisk and although not supported by End Point Manager are certified with the Grandstream video phone as well. They are not cheap though!

Thanks for the help, guys! I came across both 2N and Cyberdata. Honestly can’t understand why this stuff is SO expensive ($500 and up…).

Think I’ll stick with a standard intercom as the phones I’m using doesn’t have video capabilities.

Could you please explain the way this should all be connected physically at the door (how do i connect it to the lock, how to wire everything, etc…), as well as how should I configure my FreePBX to work so that I can accept intercom calls and open them?

The intercom is simply a SIP extension. You program the number you want it to dial (usually a ring group) when the button is pressed.

As far as he lock, the Intercom has standard form C closures. This provides both normally opened and normally closed circuits to support any type of device.

You will need to run a CAT 5 to the door/gate. If the run is over 300ft pickup a pair of inexpensive fiber transceivers and run multimode fiber.

You can pragmatically use standard twisted-pair telephone wiring if you limit the network devices to 10mb/s, it is quite within the specs.