The flame detectors are used for the supervision of gas flames, yellow- or blue-burning oil flames and for ignition spark proving. High sensitivity.

• With this type of flame supervision, the UV radiation emitted by gas or oil flames is used to generate the flame signal.

• The radiation detector consists of a UV-sensitive cell with 2 electrodes, which ignite when illuminated with radiation in the 190...270 nm range of the spectrum, thereby triggering a current in the flame detector circuit.

• The UV cell does not respond to glowing firebrick in the combustion chamber, daylight or light from the boiler room illumination.

The die-cast alloy flame detector head is sealed with a quartz-glass lens. In addition to the plug-in UV cell, the head contains a rotating shutter which – for the purpose of continuous testing of the UV cell’s striking and extinction voltage performance – interrupts the UV radiation at the rate of 3 times per second. The shutter is driven by a synchronous motor which is suited for continuous operation.

The flame detector is attached to the viewing tube by means of a flanged mounting coupling which has a 1 in. internal thread. A 3/8 in. tapping on the side of the coupling enables a cooling air conduit to be connected, provided that dry, dust- and oil-free compressed air is available.