A PLC is a device used for automated control in industrial production. It can generally be used directly in industrial environments without requiring special procedures. However, despite its high reliability and strong anti-interference capabilities, as mentioned above, harsh production environments, intense electromagnetic interference, or improper use can lead to program or computational errors, resulting in erroneous inputs and outputs. This can cause equipment malfunctions and misoperations, compromising the normal operation of the PLC. To improve the reliability of a PLC control system, PLC manufacturers need to enhance the anti-interference capabilities of their equipment. Furthermore, it requires close attention during design, installation, and maintenance, with multi-party cooperation to effectively address the problem and strengthen the system's anti-interference function. Therefore, the following issues should be noted during use:
(1) Temperature: PLC requires an ambient temperature of 0 to 55℃. When installing, it should not be placed under components that generate a lot of heat, and the surrounding space for ventilation and heat dissipation should be large enough.
(2) Humidity: In order to ensure the insulation function of PLC, the relative humidity of the air should be less than 85% (no condensation).
(3) Vibration: The PLC should be kept away from sources of intense vibration to prevent frequent or continuous vibration at a frequency of 10-55Hz. When vibration cannot be prevented in the operating environment, vibration reduction measures must be adopted, such as using vibration damping rubber.
(4) Air: Prevent corrosive and flammable gases, such as chemical acids and alkalis. In environments with a lot of dust or corrosive gases in the air, the PLC can be installed in a well-sealed control room or control cabinet. For example, in power plants, dry slag discharge and dry ash removal, enclosed cabins were added in the later stages of infrastructure construction.
(5) Power Supply: PLCs have a certain degree of resistance to interference from power lines. In environments with high reliability requirements or particularly severe power interference, a shielded isolation transformer can be installed to reduce interference between the equipment and ground. Generally, PLCs are supplied with 24V DC output to the input terminals. When an external DC power supply is used at the input terminals, a DC regulated power supply should be selected. Ordinary rectified and filtered power supplies, due to ripple effects, can easily cause the PLC to receive incorrect information.
Disclaimer: This article is a reprint. If it involves copyright issues, please contact us promptly for deletion (QQ: 2737591964). We apologize for any inconvenience.
