摘要 |
The present invention relates to a flame detector for detection of the presence of a flame or spark in front of the detector comprising a UV sensitive photocathode (12; 21) and an anode (14; 22), respectively, wherein the UV sensitive photocathode is oriented such that UV light from a flame present in front of the detector can strike the photocathode; a voltage supply unit (18; 23) connected to the UV sensitive photocathode and to the anode to force photoelectrons emitted from the UV sensitive photocathode when struck by UV light from a flame present in front of the detector to move towards the anode; and a readout arrangement (15-17; 24) adapted to detect charges induced by electrons moving towards the anode to thereby detect the presence of a flame in front of the detector. The flame detector can be combined with an alarm unit (33) to form an automatic alarm (31). |