I am looking to use some 50mm X 50mm trunking around the garage to take mai ns wiring. I would also like to run some Cat5e cables in the trunking but I cannot find any that will take a separator and was wondering if it was acc eptable to install smaller trunking within the larger one and enclose the l ow voltage cables within?
Richard
I could be wrong but had always assumed the requirement was based on the need for separation between power and data to reduce interference/inductive/capacitive coupling.
Putting trunking within trunking might increase the electrical insulation but the mains cable itself should have more than adequate insulation anyway.
If you don't want to use the larger dado trunking, can't see why trunking within trunking wouldn't be acceptable.
Why use 50 x 50?
Bill
Bob Minchin formulated the question :
IEE Regs do not care about that, but it states something about the insulation of the lower voltage cables has to be to mains spec.. Data cables are not rated for mains voltages, so there has to be some sort of physical barrier separating them. I would imagine that the data cable in its own trunking would be OK.
Personally I'd not want to get data cables anywhere near long runs of mains wiring due to inductive effects that might affect their efficiency. Brian
I see no problem with that.
The IET regs IIRC say that you can put ELV (what normal people call low voltage, the IET calls extra low voltage) cables in the same containment as LV (mains) if all the cables' insulation is rated for the highest voltage present.
I'm planning to put telephone extension cable in uPVC trunking carrying 2.5mm cable. So I've bought some plastic angle that is slightly narrower than the space between the lid and the bottom of the trunking.
Plan is put lengths of good quality double sided tape on the angle and insert it into the trunking beside the mains cable.
The telephone cable will then be run in its own compartment.
No. IIRC the whole idea was to put AT LESAST two layers of insulation between mains and datas. Trunking need not carry T & E - it can carry solid core mains in single conductors.
Again the whole idea is to prevent shock from the data wiring should it all chafe through.
That is a beter explantion of what I understand to be the case, than mine.
+1
Can't see anything wrong with that as far as electrical safety is concerned. I'd be a bit more worried about common mode induction from the mains into the Cate5e. What are the Cat5e's going to be used for?
Granted they were not long straight parallel runs, but if the Cat5e is being used for ethernet, you'd have to try hard to break it - I've seen Cat5e piled on high current mains cables (from 32A flex to large SWA) under computer room floors and never a problem at gigabit speeds - the twisted pair balanced approach works very well. And there is magnetic isolation at both ends no common mode rejection is pretty solid.
Just to clarify some points. 50 X 50 trunking is chosen because the plan is to drop cables from the trunking at ceiling level in conduit to sockets an d switches and that size is convenient to work with when it comes to joinin g conduit to trunking.
The Cat5e will mainly be to connect to CCTV cameras using POE and a single computer port.
I am inclined to agree with Tim Watts having seen exactly the same done by profesionals and having previously installed dado rail trunking with both t elecoms wires and Cat5e running in the separated channels, I noted that dis tance wise there was little separation between them and the mains wires and was never aware of any interference in either.
Richard
HomeOwnersHub website is not affiliated with any of the manufacturers or service providers discussed here. All logos and trade names are the property of their respective owners.