DC resistance of cable
DC resistance of cable
(OP)
All manufacturers mention value of DC resistances for their cables. We normally use ac resistance for calculation purpose. What is nescessitiy of mentiong DC resistance then? Is it only for confirmation to limitation of resistances to standard?
Please help me out. In advance, thanks....
Please help me out. In advance, thanks....






RE: DC resistance of cable
Regards
Marmite
RE: DC resistance of cable
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If we learn from our mistakes I'm getting a great education!
RE: DC resistance of cable
Not sure, though, if DC and AC differs much in a signal cable. Don't think so.
Gunnar Englund
www.gke.org
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100 % recycled posting: Electrons, ideas, finger-tips have been used over and over again...
RE: DC resistance of cable
Skin factor depends upon conductor overall diameter and frequency.
As Skogsgurra said for control cables of small diameter conductor cables this factor is close to 1.
For large power cable conductor the difference begins to be significant and for cable heat calculation purpose, where one needs to appreciate accurately the power losses,it is important, as Marmite said.
For three core cable or three single phase cable there is another factor to mention: the proximity factor.
The proximity effect is the phenomenon where the current will flow mainly in the opposite side of the conductor vecinity –as if the proximity of the second conductor press the current in the opposite side.
This factor may be significant also for large conductor and elevated frequency.