The mat alarm is used for monitoring the integrity of the heating element during installation and whilst the floor finish has been laid. Whilst the mat alarm is able to pick up large damage it is unable to pick up very small damage so it is important to still test your underfloor heating by testing the resistance and performing a mega test. The mat alarm needs to be switched on at all times whilst the system is being laid and until the floor finish is complete. If the cable is damaged the alarm will sound to let you know the floor heating has been damaged.
This video shows how to correctly wire up a Thermogroup alarm to monitor cable integrity during the installation of the Underfloor Heating.