For 220V control circuits, unshielded cables can be of any length without causing interference that would affect the operation of the system
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It is a 220V control circuit; unshielded cables can be used without issue, as they do not cause any interference with the system’s operation. Due to poor communication between the design agency, the equipment manufacturers, and the client, these control cables were ordered as unshielded ones. It is an ABB control system with a 220V input, and the distance between the cables is not too great. Is there anyone with experience in this area?
220V digital switch? It is generally used for coils, so there’s no major issue. The interference mainly comes from a large number of analog signals, while for digital signals it is primarily an issue with induced voltage.
Thank you for your reply. The issue lies in the induced voltage; the length of the cable affects the induced voltage, which in turn impacts operation.
As long as the grounding in the MCC room is properly handled, there’s no major problem; I’ve seen systems continue to operate even with an induced voltage of 100V.
Although unshielded cables are used for digital signals, shielded cables are always used for analog signal transmission, right? If possible, it is best to run this section of cable through conduit or use a separate tray for its installation; we have encountered situations where interference caused the train to stop suddenly. Additionally, any spare cables that are not in use should also be properly grounded.
Computer shielded cable for analog signals. The digital signals are not shielded; the cable trays have partitions, and the distances range from several dozen meters to no more than 140 meters.