F200K Ex explosion-protected compact flame scanner

F200K Ex and F200K Ex-II are the Ex versions of the F200K compact flame scanner, designed for potentially explosive atmospheres. The flame sensor and the switching amplifier share one housing, so no separate evaluation unit is needed. The scanner supervises the flame in continuous operation on firing systems with one or more burners and is certified to SIL3 under DIN EN 61508-2. The Ex design opens F200K up to further uses, above all in the chemical and petrochemical industry. F200K Ex is marked for Ex zones 1 and 21, F200K Ex-II for Ex zones 2 and 22.

Both models are available with a UV-2 (210–380 nm) or an IR-1 (1200–2800 nm) sensor. UV-2 is preferred for oil, gas and special gases like refinery gas, blast furnace gas and hydrogen; IR-1 for oil, gas, wood and coal firing with heavy flue gas recirculation, and for yellowish waste gases that emit no UV or whose UV part is screened by water vapour and dust. Sensitivity is set in several stages and the flame frequency is evaluated digitally; the two-channel design monitors itself electronically. The supply is 24 V DC ± 20 %, power consumption is up to 4 W and the analogue output is 0/4…20 mA.

F200K Ex has a nickel-plated, varnished aluminium housing rated IP66; it operates at ambient temperatures of -40…+65 °C with the UV-2 sensor and -40…+60 °C with IR-1, and it mounts only on threaded FV30 or FV40 brackets. F200K Ex-II is rated IP66/67, operates at -40…+75 °C with UV-2 and -40…+60 °C with IR-1, and mounts on threaded FV30/FV40 or plug-in FH30/FH40 brackets. The FS50 cooling air housing can be used with F200K Ex-II, while no cooling air housing is offered for Ex zone 1. On F200K Ex-II, the 3 m connecting cable can be extended by up to 250 m at a 20.5 V supply. A UV-6 FO fibre-optic sensor variant is also available for F200K Ex-II in Ex zone 2.