First of welcome! You need to make sure that your alarm panel is compatible with Vera. Not every alarm panel will work. You can see a list of alarm panels here that have plugins developed for Vera:
If the alarm panel is not compatible, you will need to make sure that the panel exposes it’s interface via the serial port and that there is api available to communicate with the panel. If this is all true, you will need to create a plugin that can communicate with the panel.
Vera has a USB port on the back of it. If you can get the serial cable from the alarm panel to Vera, that’s sufficient. Failing that, there are other low-power options for getting the signal between Vera and the panel that don’t require an always-on computer.
If you can describe your house wiring layout, including how close your panel is to your LAN, we can offer suggestions.
Then there is the software side of the problem, which Garrett has already described.
Thanks for the reply. I have looked closely through the pages you suggested and think I have found enough to give this a good try!
In particular, dfad1469 seems to have good success with his Honeywell RS232 plugin and he mentions:
" I will say that I have read documentation from Honeywell that states that all security system RS232 interfaces use the same protocol. Therefore, they should all work with my plug-in, but, as you stated, that is untested."
So I will take the chance and order the RS232 lead and USB converter and see what happens!
Will update this page when I start getting it together.
An update for those looking to get more from the Honeywell Galaxy G2 alarms, there is a very well priced Ethernet device made by http://www.sm-alarms.co.uk/ that features a free app to remotely control the alarm keypad.
This might be a compromise to allow remote control of the alarm and a multi-sensor could be used to tell Vera if sensors/alarm have been triggered.