UTP is unshielded, and would be susceptible to electromagnetic interference. STP would do better. But you should never lay any kind of network cable next to power lines. Try to avoid it whenever possible.
is electric cables(high voltage)has an effect on the speed of connection if these cables is close to the CAT5 UTP cables which run from the switch to pcs?
what types of cables is affected?and is there types not affected

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