Cat 5 screened data cable

[fredrico]

Afternoon. The cat 5 data screened cable, or some people call it shielded cable. I am not being stupid here, this cable still has to be run seperate from 230/415v cable runs doesnt it? Just because its screened does not mean it can be run with other cable bands. Also If installing the cat 5 cable on cable tray, with 230/415v cable runs, what sort of distances do you have to keep it from the higher voltage cable, or just run it on its own cable tray. Not done much data cable before. Cheers.

 

[mayfair]

Dont think you should have problems as long as your using a good quality cable. When you say long runs ..How Long?

 

[Spoon]

On our presses we don't bunch comms cables with power cables, especially if they are long runs. If running the two on cable tray we usually call up 50x50 trunking and put the comms in that. But as mayfair says, your shouldn't have a problem with short distances, but still try and keep them as separated as much as possible.

 

[fredrico]

Not sure yet, 20 metres , maybe.

 

[Spoon]

20 meters, i would keep them separated.

 

[fredrico]

thanks for your replies, spoon and mayfair. i will run them seperately then.

 

[fredrico]

PS, out of interest, what does the screening do differently to the non screened cable?

 

[Spoon]

Just had a work with one of the guys who suggests you look at ANSI-TIA-EIA 568B Standard. This says 100mm distance if run in parallel.

 

[johnboy6083]

PS, out of interest, what does the screening do differently to the non screened cable?

it will absorb the magnetism from the power cable, and drain it to earth. this will prevent "noise" on the data cable.

bear in mind that if cables are run together, all of them must have insulation, rated to the highest voltage present.
if not, then they must be seperated either by using different containment, or the use of a divider made from earthed metal.

 

[mayfair]

Other things to remember:-
Cat 5 cables can be bent at a radius approximately 4 times the diameter of the cable.
The specifications for networking specify a max 100 metre length between active devices.[SUP]http://en.wikipedia.org/wiki/Category_5_cable#cite_note-8[/SUP] This allows for 90 metres of fixed cabling, two connectors and two patch leads of 5 metres, one at each end.
The Voltage rating on most standard Cat5e cable is 300v

 

[aptsys]

it will absorb the magnetism from the power cable, and drain it to earth. this will prevent "noise" on the data cable.

bear in mind that if cables are run together, all of them must have insulation, rated to the highest voltage present.
if not, then they must be seperated either by using different containment, or the use of a divider made from earthed metal.

There is no cable shield that will 'absorb' magnetic radiation - this is only possible through distance and high magnetic permeability metal alloys. You can only reduce RF, electrostatic radiation and capacitive coupling effects with traditional shielded cables.

 

[Jimmy Boy]

Hi chaps no long see been busy.

As a leccy I have just completed a C&G a 367-1-101 and a 3667-02 Unit 4 and passed with flying colours.

I loved the Physics of the coms course, learning about cross talk, far end and near, attenuation, ACR, delay skew and ACR ( Attenuation to cross talk ), and NVP as well, the whole testing procedure was amazing, to see what happened if you didn't keep the twists tight in the IDC cons,and as for TDM..Time Domain reflectometer..Thats just such a cool name

 

[supasparxs]

Afternoon. The cat 5 data screened cable, or some people call it shielded cable. I am not being stupid here, this cable still has to be run seperate from 230/415v cable runs doesnt it? Just because its screened does not mean it can be run with other cable bands. Also If installing the cat 5 cable on cable tray, with 230/415v cable runs, what sort of distances do you have to keep it from the higher voltage cable, or just run it on its own cable tray. Not done much data cable before. Cheers.

If you are using screened Cat5e make sure you earth the screen, if you don't the un-earth screen acts as an aerial and attracts interferance

 

[telectrix]

spam alert

 

[grantr37]

on own 50mm cable tray away from power cables, you can clip 50mm basket onto the same screwed rod with the 55mm L bracket type clips (think they are made by Caddy Clip company or similar) they have a 6mm hole for fixing tray onto them with roofers and have a spring clip......will find them on ebay I imagine...

 

[dragon-av]

Very true, commonly there is UTP Unshielded, FTP, STP Shielded FTP overall screen, STP is a shield on each pair as well, but without using IDC or pulgs with the earth connector (rare) they are worse than UTP. 2" minimum separation and try not to have long parallel runs with power and cross at 90 degrees.

Cat6 is even stricter on bend, twist and crosstalk....

 

[billyb76]

If you using FTP cable it 50 mm away, but as said above the Drain wire needs to be earth at the cab end, or the drain wire acts as an aerail.
If using UTP cable it needs to be 200 mm away from power.

This is of the net:-
Current standards clearly define the separation between power and data cables. For instance, the minimum separation distance between unscreened power and unscreened UTP cable is 200 mm. This is reduced to 50 mm for screened data cable and to just 30 mm if the power cable is screened. Electro-magnetic interference from power cables can reduce the performance of data cables, particularly speed of data transmission.
Using a steel divider in a metal cable tray significantly reduces the separation required between power and data cables. If these are unscreened, separation can be as low as 50 mm, assuming the divider is both physically and electrically continuous.