From the mobile phone,
command can be send via SMS to the Controller, which
in turn interprets the command and then activates the
required ‘switch’ to control the electrical item. As long
as there is GSM mobile phone signal coverage, it is
possible to control all electrical items from anywhere in
the world. The system is easy to operate, and is secure in
that only pre-determined mobile numbers can operate
the GSM Controller. The installation of the GSM
Controller is relatively simple and can be adapted for
any existing home system. Control of lights and geyser
are done via the electrical distribution board (circuit
breakers).The block diagram of system is as follows: