I’m pretty new to Home Assistant but I’ve managed to get quite a long way in a short time, thanks to the great ideas and support available here.
I’ve recently purchased a Smanos X500 Burglar Alarm. This is a cheap and quite simple solution but seems to be reasonably capable and as I live in a low crime area it didn’t seem worth spending a lot of money.
The X500 uses sms messaging as its main interface and has a feature that allows the user to arm the alarm system by sending a code by sms. I wanted to find a solution to allow the alarm to be armed using Alexa and succeeded by using Home Assistant and Twilio.
Twilio is well documented here already but essentially you need to sign up for Twilio and pay, the free service will not work as the sms messages that are sent, include a short piece of text at the start of the message that would not be recognised by the alarm panel.
I then wrote a very simple script in Home Assistant that sends the appropriate numeric code to the alarm panel using Twilio. I then got Alexa to discover new devices to add the new script ‘burger alarm’ as a smart home device. Thus I can arm the burglar alarm by using the instruction - ‘Alexa turn the burglar alarm on.’
There were a few bumps on the way. The alarm system will only interact with known numbers and Twilio uses the E.164 format for telephone numbers, +447777777777 rather than 07777 777777. It took a few attempts to get the alarm system to recognise the number in this format.
It also seemed sensible to route the response text from the alarm to my mobile phone so that I know that the alarm is set correctly. Although given the cost of sending the confirmation sms through Twilio I will probably disable this once I know the system is reliable. This involved creating a routine in Twilio’s studio facility, again all well documented on the Twilio web site.
The cost of running this service is $0.04 for each text sent from Twilio and $0.0075 to receive. So at the moment each time I arm the system it costs $0.0875. Of course it would be cheaper to use the keypad or keyfob, but seriously, where’s the fun in that?
Anyway, if anyone would like more details I will be pleased to help.