ian.cant Posted October 13, 2004 Posted October 13, 2004 csa = cross sectional area (the size of the core) GPO = general post office (the company that ran the telephone network back in the 70/80,s.) Telephone cable is still refered to by some suppliers as GPO cable.
Guest Posted October 13, 2004 Posted October 13, 2004 also alarm cable has a CSA of 0.2mm compared with 0.5mm of twisted pair.The twisting of the cables then adds additional CSA to the whole cable and alarm cable is more flexible and has a smaller bend radius 27184[/snapback] here we have to remeber that UK type alarm cable is 0,22 mm2 but twisted pair core diameter is 0,5mm which makes it 0,19634954mm2 (approximately) also patch cable is not tinned.. twisting doesn't add additional CSA to the cable but makes a core a bit longer than a cable run. this though is something like 0,1% (maximum) and depends of the pair number because separate pairs have different twisting cycle.
Guest Posted October 13, 2004 Posted October 13, 2004 ok.. i have sent an inquiry about CAT5 cable that achieves UK standards and regulations for an alarm cable. (They have already promised that my greetings to all UK security installers can be written to the surface of the cable just next where it says "UK type alarm cable")
Brian c Posted October 13, 2004 Posted October 13, 2004 Georg, it is not because of regulations. It is the manufacturers that recommend using flexible multi-strand cable for thier equipment.It is also due to preference. Solid core twisted-pair cable is liable to snapping. 27181[/snapback] Dear Brian, CAT5 patch cable is not solid core. It is multi strand. 27208[/snapback] I stand corrected. It is also available as multi-strand If you don't know......ask.
Brian c Posted October 13, 2004 Posted October 13, 2004 also alarm cable has a CSA of 0.2mm compared with 0.5mm of twisted pair.The twisting of the cables then adds additional CSA to the whole cable and alarm cable is more flexible and has a smaller bend radius 27184[/snapback] ehh.. CSA?? (i don't understand) you have to remeber that cat5 bending radius is given so that 100Mb/s can still go through.. 27209[/snapback] you have to remember we're talking about using this cable for alarm installations. Why would you need such a transfer rate? If you don't know......ask.
Brian c Posted October 13, 2004 Posted October 13, 2004 also alarm cable has a CSA of 0.2mm compared with 0.5mm of twisted pair.The twisting of the cables then adds additional CSA to the whole cable and alarm cable is more flexible and has a smaller bend radius 27184[/snapback] here we have to remeber that UK type alarm cable is 0,22 mm2 but twisted pair core diameter is 0,5mm which makes it 0,19634954mm2 (approximately) 27217[/snapback] ??????????????? ???????? 1 cable has a CSA of 0.2mm The other has a CSA of 0.5mm twisting doesn't add additional CSA to the cable but makes a core a bit longer than a cable run. this though is something like 0,1% (maximum) and depends of the pair number because separate pairs have different twisting cycle. 27217[/snapback] It doesn't add CSA to the core being twisted, but it does to the overall cable. Not very much, admittedly! If you don't know......ask.
Guest Posted October 13, 2004 Posted October 13, 2004 no we don't need 100Mb/s in alarms but cable bending radius is announced so that you can still use such high transfer rate. So in alarm installations you can practically use 2cm bending radius. Maybe even tighter.
Guest Posted October 13, 2004 Posted October 13, 2004 UK type alarm cable has diameter of 0,53mm and its surface area is 0,22 square milli metres. CAT5 patch cable diameter of 0,5mm and its surface area is 0,196 square milli metres.
Brian c Posted October 13, 2004 Posted October 13, 2004 The cross sectional area is the area of a circle relative to it's radius. UK alarm cable has a CSA of 0.2mm(2) CAT 5 cable has a CSA of 0.5mm(2) So CAT 5 cable has a bigger radius/diameter than alarm cable and is, therefore, thicker. I don't think I can explain myself any more clearly than that If you don't know......ask.
Guest Posted October 13, 2004 Posted October 13, 2004 The cross sectional area is the area of a circle relative to it's radius.UK alarm cable has a CSA of 0.2mm(2) CAT 5 cable has a CSA of 0.5mm(2) So CAT 5 cable has a bigger radius/diameter than alarm cable and is, therefore, thicker. I don't think I can explain myself any more clearly than that 27232[/snapback] Cat5 seems to be 0,14 square milli metres.. --> diameter is approx 0,42 mm.. http://www.ethernetrail.com/Datasheets/Flex_cable.pdf Time to go to buy new glasses for me.. I always thought it was 0,5mm thick and it was 0,42..
Recommended Posts
Archived
This topic is now archived and is closed to further replies.