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Can you run a shielded DMX cable in the same duct as SWA power cables. Cable Ladder Size
The run is probably around 100m.
I know in the regs it states:
1. Every cable or conductor is insulated for the highest voltage present. 2. Each conductor of a multicore cable is insulated for the highest voltage present in the cable. 3. The cables are insulated for the system voltage and installed in a separate compartment of the cable ducting or cable trunking system.
For me, as usually DMX is not explicitly powering anything, and that you can also classify it as SELV, I'd say that this rule does not apply.
This classification would also be correct for fixtures that use PoE (Power-over-Ethernet) or other LED systems that send +24VDC through one (or more) pairs and DMX through another on the same cable.
We need to link 2 feeder pillars up to run led lighting control's in the city centre otherwise it will have to be done over WiFi.
There is no direct route to each pillar unless we jump from the data duct into the power duct.
BS 7671 does allow a series of exceptions to segregation of Band 1/2 cables.
As you say, if the cable is rated at the highest voltage present, no issue. Also, if SELV then no issue.
If you can classify the DMX as SELV, then you have designed away the need to be concerned with the potential issue of interference.
I wouldn't personally be able to say it can/can't be done but I would check with the cable supplier just to be sure.
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