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Cable Sizing - Derating factor
- Thread starter skm
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I'd apply this method :<br>
Suppose you have one cable only, this gives you a derating factor.<br>
Based on this derating factor, calculate the current carrying capacity of the cable (or theoretical CSA). If this is OK, you have your solution. <br>
Otherwise, use two cables, and get the new derating factor. Calculate the current carrying capacity (or theoretical CSA). If this is OK, you have your solution.<br>
Otherwise, use three cables, ....<br>
It's repetitive, but it works !<br>
Software programs are good at handling this.<br>
<br>
Good luck,<br>
<br>
<br>
Boris
Suppose you have one cable only, this gives you a derating factor.<br>
Based on this derating factor, calculate the current carrying capacity of the cable (or theoretical CSA). If this is OK, you have your solution. <br>
Otherwise, use two cables, and get the new derating factor. Calculate the current carrying capacity (or theoretical CSA). If this is OK, you have your solution.<br>
Otherwise, use three cables, ....<br>
It's repetitive, but it works !<br>
Software programs are good at handling this.<br>
<br>
Good luck,<br>
<br>
<br>
Boris
If u refer to the BS7671:1992 16th Ed., there is a table for u to refer to. it shud be a straight forward calculation. in addition, u also need to take into the surrounding temprature and installation method factors, which incidentally is included in the BS7671:1992 16th Ed. all this is in pg 188. refer to table4. you can always complie this data and do a look up table calculation. alternatively, u can request from the cable supplier for this purpose. [sig][/sig]
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