Do instrument wires need to be run in tubes or through cable trays?
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Question: Do instrument wires (in non-explosion-proof areas) need to be run in tubes or through cable trays? Plain wire will do; are there any regulatory requirements?
In non-explosion-proof areas, it is generally recommended to run instrument cables in tubes or use cable trays; this provides better protection for the cables, prevents mechanical damage and electromagnetic interference, and ensures the stability and reliability of the signals. Although it is technically feasible to lay exposed wires in non-explosion-proof areas, it is not recommended due to the risk of wire damage and safety hazards resulting from the lack of protection. The specific wiring method should be determined in accordance with the local electrical installation codes and standards. .
Instrument wiring, in a general sense. In most cases, it is necessary to install cable trays or use conduit; however, the setup also depends on factors such as the actual layout required on site, the layout needs of wires and optical fibers, the special protection requirements for instrument cables, and the impact of the environment on these cables. This information is provided for reference only.
The routing of instruments through pipes or in cable trays has nothing to do with whether they are explosion-proof or not; all cables, taking into account their mechanical strength and susceptibility to mechanical damage (as well as environmental damage such as corrosion and ultraviolet radiation), should be routed through pipes or cable trays. Except in cable trenches (where the spacing between supports is close and external damage is virtually impossible).
Priority should be given to using overhead wires; buried wires should be avoided as much as possible. If they must be used, they need to be placed in separate conduits and cannot share the same conduit as power cables. For indoor buried wires, armored cables should be used. When running them through conduits, they should not share the same conduit as power cables to avoid interference (I have encountered soft faults before, which were really troublesome). Finally, the problem was resolved after threading it separately). Standard: DL/T 5182-2021 Code for Installation of Local Instrumentation and Control Equipment, Pipeline, and Cable Design in Thermal Power Plants
The wiring for instrument signals must be supported reliably; depending on the site conditions, it is preferable to use cable trays, or cable trenches can also be used. When laying instrument signal wires, interference resistance must be taken into account; for example, they should be laid separately from high-voltage cables, avoided from running parallel to such cables, and kept away from strong electromagnetic devices. Instrument signal wires cannot be handled carelessly like ropes used for hanging clothes! !
Walk along the cable tray. Protection or no protection – it’s not mandatory.