Optical smoke detector with extended spectrum of detected smokes and with isolator
Optical smoke detector with extended spectrum of detected smokes and with isolator is intended for the automatic fire alarm signalling as a smoke detector in the analogueand addressable Fire Detection and Fire Alarm System LITES
Type MHG 262 does not contain isolator.
It responds to both visible and invisible smoke particles (aerosols) on the principle of detection of scattered infrared radiation.
The MHG 262i (MHG 262) detector is intended for co-operation with the analogue Control and Indicating Equipments (C.I.E.) MHU 110, MHU 111, MHU 115, MHU 116, MHU 117 and with the addressable C.I.E. MHU 109. The detector contains a program that evaluates the fire situation pursuant to measuring of the surrounding smoke concentration, namely in agreement with the following adjustable characteristics:
- basic sensitivity of the detector; it monitors the surrounding smoke concentration increase compared to the quiescent state, that compensates the climatic and other influences (environs temperature, pressure etc.) continuously; the basic sensitivity can be adjusted in eight degrees that must be selected with reference to the detector’s combustion gas load that the detector responds to; the basic sensitivity can be inactivated completely, or it can be set only partial.
- reaction time; the verification level of the fire situation is concerned; also adjustable in eight degrees, however they can’t be expressed by a simple time stamp, because the reactiontime depends on the time progression of the fire situation
- dustiness watch; it monitors the rest level of the detector, and upon this it evaluates the dustiness rate of the optical chamber and consequently the reliability of the detector; it canbe adjusted in seven degrees, or inactivated; it’s set in reference to the dust nuisance rate round the detector and to the setting of other parameters
Further the pre-alarm sensitivity can be adjusted, it is always higher then the alarm sensitivity. The detector self regulates its internal working characteristics, if they don’t reply to the allowable tolerance, fault warnings occur.
The adjustable characteristics can be set either into a configuration program and recorded to the detector through the C.I.E. or they can be programmed right by means of the preparation MHY 535.
The detector MHG 262i has a built-in isolator (type MHG 262 does not contain isolator), that in case of a short-circuit separates the shortcut part between detectors with connected isolators on the circle line. The detector is installed into the MHY 734 Base. For installation it is possible to use the Mounting Bar MHY 736.
The detector fulfils the requirements of the standard ČSN EN 54-7 and is certified for use in the Fire Detection and Fire Alarm System according to law No. 22/1997 Sb., in wording law No.71/2000 Sb. in EVPÚ Dubnica nad Váhom NB 1293 and relevant Government regulations.