cable news: several factors affecting cable performance
from：guichao author：admin click： 382 addtime：2017-04-14 12:31:26
ultraviolet (uv): do not use uv protection cable in direct sunlight environment.
heat: the temperature of the cable in the metal pipe or wire slot is very high,
many polymeric materials at this temperature will reduce the service life.
water: in the lan twisted pair cable moisture will increase the capacitance of the cable,
thus, the impedance is reduced and the near end crosstalk is caused.
mechanical damage (repair costs): cable repair is very expensive,
at least two terminations are required at each discontinuity.
if the shield of the cable is grounded,
must comply with the relevant standards.
the total length of the route (not only refers to the floor): the building between the use of outdoor lan cable,
its total length should be limited to 90 meters. for 100mps or 1000mbps networks,
the laying distance should not exceed this limit. such as the laying of the distance between 100 meters to 300 meters,
should choose cable.