Alarm signal transmission over central heating pipes - has transformers for signal transmission using piping as primary and secondary coils in coupled system

摘要

An alarm system for building security installations uses the pipes of a central heating system as a method of signal transmission. Sensors (6) are coupled to the primary coil (9, 10, 11) of transformers using sections of the central heating system as the secondary coils. Signals are transmitted at frequencies of 10 kHz. The alarm station receives signal over the secondary coil of a transformer with the primary coil provided by a section of the piping. The spacing between the primary and secondary coil winding is less than 3 cm.