Issues regarding the laying of power cables and instrument cables for instruments and valves
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The last edit to this post was made by 99℃ on 2026-6-24 at 16:03. I would like to ask whether the 24VDC power cables for pneumatic valves, solenoid valves, and instruments can be run together with the instrument cables, and whether the 220VAC power cables can be run in the same tray as the instrument cables, separated by a metal partition. Paragraph 6.1.1 of the “General Code for Electrical and Intelligent Systems in Buildings” GB55024-2022 states that power cables of different voltage levels shall not share the same conduits and cable trays. Power cables and intelligent cables should not be routed in the same conduit or tray
Seeing you cite GB55024-2022, indeed many people working on site need to think about it. Literally speaking, according to the specifications, it is not recommended to route power cables of different voltage levels (including 24V and 220V) together with signal cables in the same cable tray; this is especially true since signal cables are prone to interference. However, practical alternatives exist: for 24VDC power cables and instrument signal cables, if both are armored shielded cables and the load is pure DC, some projects lay them in the same conduit, but it is better to maintain a distance of ≥30 cm between them; or using a metal partition in between is even more advisable. If the signals are particularly sensitive (e.g., 4-20mA), it’s still recommended to route them through separate channels. 220VAC power cable: After adding a metal barrier, can it share a cable tray with instrument cables? The standards state that it \"should not be done\", but many design firms follow the principle of separating strong and weak electrical circuits; typically, 220VAC cables and signal cables are required to be in separate channels. Using metal partitions is a compromise solution, but its effect in reducing interference is not as good as complete separation. It is recommended to lay the cables in separate slots; if space is truly limited, the partitions must be hermetically grounded throughout, and the cables should preferably be armored and shielded. It is recommended that you take into account the drawing review requirements in the project’s location (some regions have stricter standards than the national ones). It would be advisable to consult an electrical design specialist or the local drawing review center, as the actual safety inspection and acceptance may be carried out in accordance with the strictest provisions. Additionally, note that the cable selection (flame-retardant level, voltage rating) must also be compatible with the on-site explosion-proof zones.