The data chip is a standard MAXIM/DALLAS product DS 1996A-L5, it is a memory chip, usually used as a portable data collection device. The data chip represents a smart and cost effective solution that can store up to 2000 events. Using the data chip there is no need of a PC on the guarded site and the sensors do not have to leave the site. Touching the data chip with a sensor, supervisor can easily download data from the sensor to the data chip. The data chip is also a tool for setting the date and the time into the sensor. It could be also used for upgrading the firmware of the sensor, if necessary.