What is the effect of induced voltages on telecom facilities and how does it occur?
Induced voltages on telecom wire-lines result in a voltage between conductor and ground. If very large, these voltages may break down the insulation of the conductor and circuit equipment. Induced voltage is primarily the effect of the electro-magnetic fields coupled to telecom facilities paralleling power lines. When the power line is faulted-to-ground, large short circuit currents may induce large conductor-to-ground voltage on the telecom conductors. This voltage may combine with GPR to produce serious stress to the insulation on telecom lines entering into the power station environment. 4. At what GPR and induced voltage level at a power station site should special protection of telecom circuits be applied? IEEE Standard #487 recommends this be the form of protection whenever 1000 Volts peak is met or exceeded during a power fault. 5. In what form do special protection devices come in? Originally these protection devices were magnetic devices with some auxiliary surge arrester equi
