An inductively powered sensor system includes a primary conductive path 100 capable of being energised to provide an electromagnetic field in a defined space 1. An inductive power pick-up 120 is associated with a sensor 124 and is capable of receiving power from the field to supply the sensor 124. The system includes a first sensing means to sense the power available to the pick-up 120 and control means to increase or decrease the power available to the sensor dependant on the sensed power available. A method of inductively powering a sensor, an inductively powered sensor and an animal enclosure including one or more primary conductive path of an inductive power supply are also disclosed.