The control reliability of the exhaust fan
Sometimes there is also a requirement to directly start the hard-wired linkage smoke exhaust fan when the normally closed exhaust port is manually opened. At the same time, the relevant specifications not only put forward various start-up requirements for the exhaust fan, but also mention the stop requirements, including the remote hard-wire control stop requirements for emergency control.
From the simplest manual start-stop control, to automatic control, to single-point or multi-point linkage, interlocking automatic control, the increase of parallel or sequential control levels changes the complexity of the secondary control circuit, which is critical to reliability. There is also a certain impact.
In actual engineering, there have also been some discussions on the requirements of hard-wire control. i.e. how much range should the hardwired control cover? Is more hardwired control more reliable?
The reliable realization of the control function first depends on the control simplification and reliability design of the main process. Secondly, the control method and scope of application should be studied from the perspective of reliability, and the operation characteristics and process objectives of the equipment should be studied, and the selection should be made based on the principles of simplification and optimization.
At the same time, try to use parallel mode between different control modes to avoid mutual influence; try to avoid the design of local cross-series connection.
The range of use of hard-wired controls should be properly controlled. For more complex control systems, more attention should be paid to taking effective measures in the procurement, construction, debugging, and maintenance of automatic control system equipment, components, and networks to ensure the reliability of the automatic control system. Because the reliability of the automatic control system has a global impact, and even cannot be lost.