1. Calibration cover for verification: It is stipulated in the verification regulations that the diffusion-type instrument should have a special calibration cover, and each manufacturer has its own special calibration cover, but in the actual verification, the verifier will replace it with a self-sealing bag and a self-made calibration cover. The editor thinks that it is better to use the original special equipment as much as possible, because the inner air and air intake method (bottom air intake and side air intake) of the calibration cover still have a certain influence on the response time and indication error of the instrument. of. Of course, no matter what kind of calibration cover is used when calibrating the combustible gas alarm, one principle must be adhered to. It is also strictly forbidden to be too loose, which will cause the outside gas to enter, so that the actual value of the standard gas is too small, which affects the verification result.
Second, there is no interference to the measured component: in the process of calibrating the combustible gas alarm, attention should be paid to preventing electromagnetic interference. The influence factors of the electromagnetic environment on the combustible gas alarm mainly include the following three aspects: static electricity of the human body, narrow pulse groups on the power supply and other input and output lines, and electromagnetic wave interference in the air.
3. Good ventilation is required: for the diffusion and escape of open flammable gases, if there is a lack of good ventilation conditions, it is easy to make the flammable gas content in the air of a certain part approach or reach the lower limit of explosion concentration, resulting in inaccurate test results.
Fourth, the main controller does not match the indication value of the on-site detector during the verification: in general, the combustible gas alarm is connected by the main controller and the detector in a split-line mode. The detectors are distributed in multiple outlets, and the main controller is connected to many Each monitoring network is centrally controlled, and the gas concentration of each detector is displayed independently. When the concentration of the detector gas in the environment reaches or exceeds the preset alarm value, the main controller will issue an alarm to remind the on-duty personnel to take safety measures to ensure the safety of the enterprise. Safe Production.
