Issue of laying the 380V voltage and digital signals for the electric valve together

Isn’t 380 used in electricity? Are digital signals related to instruments, or does electrical engineering also have digital signals?

When laying the trough plates, two trough plates need to be used; I’m not sure about laying them underground

As required, the power cables and control cables should be arranged separately. A distance of 100 mm, as you mentioned, should be sufficient. In our equipment, since there are fewer cables, it’s rather troublesome to arrange them separately; therefore, they are often placed in the cable trench. Proper grounding of the power cables is essential, and that part is taken care of properly； However, if the signal wires are not installed in accordance with relevant specifications, problems are likely to arise.

HG/T 20512-2000 specifies detailed requirements: the minimum distance between instrument cables and power cables when they are laid parallel to each other is 200 mm, and this distance increases as the length of the parallel installation increases.

Check the latest HG/T 20512-2014

The standards definitely say it’s not allowed, but we also need to consider different situations; sometimes, due to cost issues, it can be quite troublesome. First, determine whether there is interference; I can tell you with certainty that there is definitely interference! Secondly, it depends on you: for 380V, it depends on the thickness of the cable, the current flow (power consumption), and what type of switches are used. If it’s a control cable for solenoid valves, 220V is sufficient; for low-power devices such as solenoid valves, 380V is used. A length of 100 meters can be combined in one conduit without any major issues. However, it is not recommended to place high-voltage and low-voltage devices in the same slot; interference can occur when both are high-voltage devices, but this will not cause malfunctioning, as the induced current (voltage) will not meet the required levels~

This post was last edited by hfrs on 2016-3-28 23:05. Direct burial is fine. If you’re worried, ground the shielding layer. It’s not that armored cables cannot be buried directly.

380VAC is unlikely to cause much interference with digital signals; even if there is some interference, it will not have an impact. I’m afraid this interference might affect other signals! Because in the end, all the cables will come together again! It’s best not to take risks when it comes to interference issues! Once interference is present, it will be very difficult to eliminate!

Although costs need to be taken into consideration, industry is not civilian use; costs cannot be cut arbitrarily. Meeting regulatory requirements ensures the reliable operation of the equipment and is also a manifestation of responsibility for one’s own design.

Please, those up there! What kind of interference can 380VAC have? Magnetic field interference? Electrostatic interference? Well, if there is any interference, it’s just a little static interference; the cables are buried directly, which means their enclosures are grounded, so what kind of interference could there be?