Flame detector, e.g. for monitoring an oil or gas flame to check that the flame does not go out, is used in conjunction with an ionization sensor with both devices having a common power supply

摘要

Flame detector (2), especially for connection to an ionization sensor output (4) of a flame monitoring circuit (5). The detector comprises: a radiation sensitive component (18) that generates an electrical signal that indicates whether it is exposed to radiation representative of a flame; a conversion circuit (17) for conversion of the signal from the radiation sensitive component into a switching signal, a channel (14) that is switched by the switching signal; and a voltage supply for the voltage conversion circuit that is connected to the switchable channel. The inventive detector is two-polar, i.e. the switchable channel can be switched between two states, the first signaling the presence of a flame, the second its absence.