The audible and visual alarm is a product customized to meet the special requirements of customers for alarm loudness and installation position. Can simultaneously emit sound, light two kinds of alarm signal. Generally used in: iron and steel metallurgy, telecommunications tower, lifting machinery, construction machinery, ports, transportation, wind power generation, ocean vessels and other fields; It is an important accessory in industrial alarm system.
Precautions for the use of the audible and visual alarm:
Once the fixed installation of the audible and visual alarm is installed, its position is not easy to change, the specific application should consider the following points:
(1) Make clear the possible leakage points of the devices to be monitored, analyze their leakage pressure, direction and other factors, and draw the distribution map of the probe position, which can be divided into three grades ⅰ, ⅱ and ⅲ according to the severity of the leakage.
(2) According to specific factors such as airflow direction and wind direction of the site, judge the leakage direction of possible toxic gas when a large amount of leakage occurs.
(3) According to the density of the leaked gas (greater than or less than the air) and the flow trend of the air, the three-dimensional flow trend diagram of the leakage is integrated, and the initial setting scheme is made at the downstream position of the flow.
(4) Study whether the leakage state of the leakage point is micro-leakage or jet. If it is a small leak, the position of the point should be close to the leak point. If it is a jet leak, move slightly away from the leak point. Synthesize each kind of situation, draw up a set point plan. In this way, the number and types of acoustic and visual alarms that need to be purchased can be estimated.
(5) For places with large toxic gas leakage, a detection point should be set up every 10-20m apart according to relevant regulations. For unattended small and discontinuous operation of the pump room, need to pay attention to the possibility of toxic gas leakage, generally should be installed in the vent of a detector.
(6) For places with hydrogen leakage, the detector should be installed on the plane above the leakage point.
(7) For the medium with gas density greater than air, the detector should be installed on the plane below the leakage point, and pay attention to the characteristics of the surrounding environment. Special attention should be paid to the setting of safety monitoring points in places where toxic gases are easy to accumulate.
(8) For the open poisonous gas diffusion escape environment, if the lack of good ventilation conditions, it is easy to make the poisonous gas content in the air in a certain part close to or reach the minimum concentration of the explosion, these are the safety monitoring points that can not be ignored. According to the analysis of field accidents, more than half of them were caused by incorrect installation and calibration. Therefore, it is necessary to introduce the correct installation and verification precautions to reduce faults.