When installing PLC, avoid the following places: ①The ambient temperature exceeds the range of 0-50 degrees Celsius. ② The relative humidity exceeds 85% or dew condensation (caused by sudden changes in temperature or other factors). ③ Direct sunlight. ④ There are corrosive and flammable gases, such as hydrogen chloride and hydrogen sulfide. ⑤There are a lot of iron filings and dust. ⑥ Frequent or continuous vibration, with a vibration frequency of 10 to 55 Hz and an amplitude of 0.5 mm (peak-peak). ⑦Shocks exceeding 10g (gravitational acceleration) [3].
In order to make the control system work reliably, the programmable Mitsubishi PLC controller is usually installed in a control cabinet with a protective shell to prevent dust, oil, and water splashing. In order to ensure that its temperature remains within the specified ambient temperature range, there should be sufficient ventilation space for the installation of the machine, and the space between the basic unit and the expansion unit should be more than 30 mm. If the surrounding environment exceeds 55 degrees Celsius, electric fans should be installed and forced ventilation.
In order to avoid electrical interference from other peripheral equipment, the programmable Mitsubishi PLC controller should be as far away as possible from high-voltage power lines and high-voltage equipment, and a distance of at least 200 mm should be left between the programmable Mitsubishi PLC controller and high-voltage equipment and power lines.
The PLC power supply is 50 Hz, 220 volts ± 10% alternating current.
If the power fails and the interruption time is less than 10 milliseconds, the PLC operation will not be affected. If the power supply is interrupted for more than 10 milliseconds or the power supply drops more than the allowable value, the PLC stops working and all output points are disconnected at the same time. When the power is restored, if the RUN input is turned on, the operation will automatically proceed [3].
For interference from the power line, PLC itself has sufficient resistance. If the power interference is particularly serious, you can install an isolation transformer with a transformation ratio of 1:1 to reduce the interference between the equipment and the ground.