This research paper discusses issues regarding the impact of temperature on the tripping thresholds of intrusion detection system detection circuits. The objective of conducted studies was the verification of a hypothesis assuming that the variability of an intrusion detection system’s (considered as a whole) operating environment temperature can impact the electrical parameters of its detection circuits significantly enough so that it enables a change in the interpretation of the state observed within a given circuit fragment from the state of “no circuit violation” to “circuit violation”. The research covered an intrusion detection system placed in a climatic chamber with adjusted temperature (−25.1 ÷ +60.0 [°C]). The analysis of the obtained results enabled determining the relationships that allow selecting detection circuit resistor values. It is important since it increases the safety level of protected facilities through proper resistor selection, thus, correct interpretation of a detection circuit state.

The article reviews issues associated with the operation of stationary and non-stationary electronic fire alarm systems (FASs). These systems are employed for the fire protection of selected buildings (stationary) or to monitor vast areas, e.g., forests, airports, logistics hubs, etc. (non-stationary). An FAS is operated under various environmental conditions, indoor and outdoor, favourable or unfavourable to the operation process. Therefore, an FAS has to exhibit a reliable structure in terms of power supply and operation. To this end, the paper discusses a representative FAS monitoring a facility and presents basic tactical and technical assumptions for a non-stationary system. The authors reviewed fire detection methods in terms of fire characteristic values (FCVs) impacting detector sensors. Another part of the article focuses on false alarm causes. Assumptions behind the use of unmanned aerial vehicles (UAVs) with visible-range cameras (e.g., Aviotec) and thermal imaging were presented for non-stationary FASs. The FAS operation process model was defined and a computer simulation related to its operation was conducted. Analysing the FAS operation process in the form of models and graphs, and the conducted computer simulation enabled conclusions to be drawn. They may be applied for the design, ongoing maintenance and operation of an FAS. As part of the paper, the authors conducted a reliability analysis of a selected FAS based on the original performance tests of an actual system in operation. They formulated basic technical and tactical requirements applicable to stationary and mobile FASs detecting the so-called vast fires.

The safety of public utility facilities is a function not only of effectiveness of the electronic safety systems, used for protection of property and persons, but it also depends on the proper functioning of their power supply systems. The authors of the research paper analysed the power supply systems, which are used in buildings for the access control system that is integrated with the closed-circuit TV. The Access Control System is a set of electronic, electromechanical and electrical devices and the computer software controlling the operation of the above-mentioned elements, which is aimed at identification of people, vehicles allowed to cross the boundary of the reserved area, to prevent from crossing the reserved area and to generate the alarm signal informing about the attempt of crossing by an unauthorised entity. The industrial electricity with appropriate technical parameters is a basis of proper functioning of safety systems. Only the electricity supply to the systems is not equivalent to the operation continuity provision. In practice, redundant power supply systems are used. In the carried out reliability analysis of the power supply system, various power circuits of the system were taken into account. The reliability and operation requirements for this type of system were also included.

Miniature fuses as an anti-damage subsystem perform the important function of protecting electronic devices and systems against permanent damage that may result in electric shocks, fire risks, etc. Their role becomes particularly important when they are installed in such special systems as electronic security systems (ESS). For this reason, there is a need for practical verification of their protective properties. The article presents the results of destructive tests of the circuit-breaking time of miniature fuse-links considered in terms of their usefulness in the ESS with the use of a passive experimental add-on, developed at the Military University of Technology in Warsaw. The characteristics of the measuring attachment circuit and the measurement methodology used were presented. Based on the obtained measurement points of the obtained time–current characteristics, an attempt was made to develop their mathematical model using numerical methods in the field of non-linear regression, using the least squares optimization method (Levenberg–Marquardt algorithm). An exemplary classification of miniature fuse-links has been proposed due to their protective properties of circuits in the context of their use in electronic security systems. The considerations were summarized with an economic analysis of the tested fuse links. The conclusions include proposals for changes to the provisions of the European standard PN-EN 50131-1:2009 “Alarm systems: Intrusion and hold-up systems Part 1: System requirements” and Polish Defence Standard NO-04-A004-8 2016 “Military facilities. Alarm systems. Part 8: Operation”.

The objective of this article was to determine, in practice, whether the break time t_w of safety fuses can impact the security level provided by electronic security systems (ESSs) that utilize the aforementioned elements as their components. This was the purpose of the conducted destructive testing aimed at estimating the break times for a certain random number of glass tube, miniature 5 × 20 (mm) fuse links with rapid operating characteristics, without a quenching medium and with a rated overcurrent intensity of 0.5 (A) by the selected manufacturers. For this purpose, a dedicated measuring attachment that enables forcing the flow of overcurrents with selected intensities in the range of 1.5 ÷ 11.5 (A) through the studied fuse links has been developed. The obtained results showed that the ratio of the break times between the best and the worst products in the entire tested range of overcurrents ranges from 5.41 (for 3.5 (A)) to 7.80 (at an overcurrent of 9.5 (A)). Statistical analysis of the measurement uncertainties proved that the obtained results of the break time do not depend on the applied research methodology or measuring equipment but are almost exclusively the result of the manufacturing spread of the tested components. Interestingly, the economic analysis did not bring clear conclusions. In this case, the products with the worst break time t_w turned out to be almost three times cheaper than the best fuse-links. What is more, the collective packaging of the product that turned out to be the best was cheaper than the next one in the list by almost USD 2.00.

This paper presents an analysis of the impact of conducted and radiated electromagnetic interference affecting the electrical circuits of electronic security systems (ESS) operating over wide areas. The Earth’s electromagnetic environment is heavily distorted by intended and unintended (stationary or non-stationary) sources of radiation. The occurrence of electromagnetic interference in a given environment where an ESS is in use is the cause of damage or malfunction of the entire system or its individual components, e.g., detectors, modules, control panels, etc. In this article, the authors conducted an assessment of the electromagnetic environment where ESS are operated and conducted studies of selected sources of interference. For selected ESS structures, they developed models of the impact of conducted and radiated interference on the process of using these systems in a given environment. For selected technical structures of ESS, the authors of this article developed models of the operation process. They also carried out a computer simulation to determine the impact of natural and artificial electromagnetic interference occurring on the process of using these systems in a given environment over a wide area. The considerations carried out in this article are summarized in the conclusions chapter about the process of using ESS in a distorted electromagnetic environment.