First some background –
Envirotxt is a plug-in sensor that monitors power outages & temperature. Envirotxt uses a SIM card to send real time text message alerts over the GSM (mobile) network. Envirotxt is simple to install and very easy to use, just plug it in and send it a text message .. it’s as easy as that! Envirotxt will send a text message alert straight to your mobile phone as soon as there is a power cut or when the temperature gets too low/too high.
An external temperature sensor is available and you can set separate ranges of temperatures for both sensors. Its also possible to send alerts if the temperature changes rapidly in a short time (for example fire / draughts).
The problem I had was the process that you use to send updated instructions to the unit were being ignored !! The process is to send texts for example #01# to the unit and it responds with the result of the requested change.
In the end the tip that resolved it was to reset the unit to factory defaults and then set the individual temperature ranges for the internal and external temperatures sensors – then activate them and add the mobile numbers you want to be alerted.
The unit is simple to set up and on a number of occasions has paid for itself when air conditioning has been accidentally turned off. There are a range of uses for the device – you can get more from https://www.openxtra.co.uk/tekview.html
You can order the device or get more info from OpenXtra – link here