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ajlelectronics
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I'm not sure if it is an EMI issue or safety, but I had an idea that 2" separation was recommended.
daedalusminos
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You can buy EV Ultra cable which has CAT 5e incorporated in the bundle
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ajlelectronics
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Interesting. It clearly isn't an EMI problem then.
MetalMonkey
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Sharing of ducts for data and power (Band I and Band II) is prohibted under BS7671 (528.1).
Several reasons.
Even with twisted pair they are susceptible to induced or capacitive coupled noise. Increasing the separation distance between the cables helps.
The main concern from the point of view of the regulations is about the danger of mains voltages appearing on low voltages cables – i.e due to a damaged cable.
Mains cables are designed to be insulated for mains voltages, whereas data cables aren’t.
I believe the EV cables get around this as they should have a screen around the data cable which acts as both interference suppression and must be capable of carrying any fault current.
Basically its non compliant and generally a bad idea to run them together, not least because it’s a lot easier to have two dedicated ducts to pull cables though and very little extra effort to put in two ducts when you have dug one trench.
If you are desperate to run everything in one duct you could get around it by using fibre with a couple of media converters at each end.
Several reasons.
Even with twisted pair they are susceptible to induced or capacitive coupled noise. Increasing the separation distance between the cables helps.
The main concern from the point of view of the regulations is about the danger of mains voltages appearing on low voltages cables – i.e due to a damaged cable.
Mains cables are designed to be insulated for mains voltages, whereas data cables aren’t.
I believe the EV cables get around this as they should have a screen around the data cable which acts as both interference suppression and must be capable of carrying any fault current.
Basically its non compliant and generally a bad idea to run them together, not least because it’s a lot easier to have two dedicated ducts to pull cables though and very little extra effort to put in two ducts when you have dug one trench.
If you are desperate to run everything in one duct you could get around it by using fibre with a couple of media converters at each end.
This PDF has the relevant info , seems to be a few differences on spacing depending on type of cable and the length of the run.
Thats a double insulated mains cable inside a separate sheath and of a flexible type which they mention as requiring no spacing (might depend on length, check the small print etc.
).SWA is mentioned as being a shielded cable so also makes its installation requirements different.
I didn't actually know the bit about distance from fluorescent lights which I thought was interesting.
Stu
qwakers
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it is a issue of emi, it can cause some weird events if the cat5 is unshielded. my network connected projector resets every time my central heating boiler lights, the cables cross within 1ft of each other and more separation isnt possible. weird issues like that are what happens if they're too close. shielding negates the issue, for the most part.
