Switchgear Protections Set 3

In phase with the arc current ✘ None of the above ✔

current carrying contacts called electrodes ✘ circuits to break the system ✘ transformers to isolate the two systems ✘ any of the above ✔

transposing transmission as well as communication lines ✘ increasing the height of the trans-mission line tower ✘ increasing the distance between the two lines ✘ all of the above ✔

Inrush protection ✘ Distance protection ✘ Time graded and current graded over current protection ✘ Both (B) and (C) ✔

Isolator ✘ Oil circuit breaker ✘ Air break circuit breaker ✘ Rewireable fuse ✔

merz price percentage differential protection ✘ mho and ohm relays ✘ horn gaps and temperature relays ✘ earth fault and positive sequence relays ✔

mechanical vibration ✘ insulation failure ✘ loose connection ✘ impulse voltage ✔

steam turbine generators ✘ gas turbine generators ✘ hydro-electric generators ✘ all of the above ✔

distribution transformer ✘ generator transformer of the power plant ✘ auto-transformer of the power plant ✘ station transformer of the power plant ✔

single bus ✘ double bus, double breaker ✘ main and transfer bus ✘ all of the above ✔