The specific requirements that appear in addressable fire detection and alarm systems and the shortcomings of the existing addressing methods were discussed. A new method of addressing of detectors was proposed. The basic principles of addressing and responding of a called element are stated. The sensitivity to electromagnetic disturbances is one of the greatest problems of the proposed addressing method -counting type of addressing. The proposed solutions of this problem were verified

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... tally. The paper also gives the conditions and results of the experiment. The counting addressing method was developed for specific requirements in fire detection and alarm systems, yet its speed and reliability justifies its use in the acquisition of data on slowly variable parameters under industrial conditions. Keywords: Fire detection, intelligent sensor, alarm system, computer communications. quently contradict each other [1]. Before we proceed discussing possible ways of addressing, we will give a list of peculiarities which make addressability in fire detection and alarm systems a challenging task. The obligatory request in fire detection and alarm systems is power supply and communication lines for addressable element (AE) must be realized through the same pair of conductors. Communication in computer systems is realized through special communication lines. This causes an additional problem in AE -extraction of communication signals from a line powered by d.c. voltage, 24 V. At the same time, it is necessary to solve the problem of generating communication signals in the computer which generates counting pulses, polling addressable elements and interprets their responses (usually cold central station, control panel or main console) [2] . Communication requirements in addressable fire detection and alarm systems are quite reduced in comparison with computer communications, and include: -addressing (polling AE), -command ON/OFF (for command AE), -Response of the called AE.