Like many other I didn't want to install my Vera 3 (or upcoming Control4 HC-300) or computer in the same area as my alarm panel nor did I want to run a long USB or serial cable. So, I developed this small controller based on the Raspberry Pi board and the AD2PI kit. The RPi board is convenient to use for this purpose because it is inexpensive ($40) and has an OS with drivers for ethernet, WiFi, serial and USB interfaces built-in (Raspi Linux). I modified Ser2Sock so I could easily run two instances at the same time and added WiFi, ftp, watchdog timer, and web server support and the capability to configure it via the web. The RPi is way overkill for this purpose but it's cheap and makes a nice package.
The power supply is a tiny unit sold for use in minature drones and as such is very reliable. It accepts from 7 to 42 volts as input and outputs 5.2 volts at up to 20 amps. Again, overkill as far as current requirements but the size, reliability, and flexibility make it very attractive. It has the capability to power other devices that operate from 5v if needed as long as you don't exceed the capability of the panel it's attached to. To use it like I'm using it though the available current is fairly low since the panel is only spec'd to provide a max of 750ma at 13 volts. With the efficiency of this switching supply that means I can draw a maximum of about 1.5 amps at 5v. More than enough for the RPi but one must allow for panel keypads and such. On the safe side I'd limit it to about 0.5 amps given measurements I've taken on my panel
Features:
- Standalone and turn-key
- WiFi and ethernet interfaces
- Uses the AD2RPI interface
- Also provides a RS-232 interface to the serial port of my alarm panel (Vista 128BPT)
- Web interface for configuring WiFi and ethernet
- Watchdog time which automatically reboots the device if it locks up for any reason
- Once configured, automatically connects to WiFi or hard-wired network
- Can be accessed by any device compatible with Ser2Sock including Vera, the alarm decoder keypad, and other HA software
- Powered via a small switching power supply directly from the alarm panel which has enough current to also power another device limited by the current available from the alarm panel.
- Continues to run as long as the alarm panel battery lasts in the event of a power failure.
Here's a photo: