Switchgear protections

power

current

voltage wave

all of the above

heavy loads

internal short-circuits

external short-circuits

all of the above

slow making and breaking of load circuit contacts

foreign matter on the contact surface

too low contact pressure

all of the above

mechanical vibration

insulation failure

loose connection

impulse voltage

zero sequence currents only

positive sequence currents only

negative and zero sequence currents

zero, negative and positive sequence currents

current during abnormal condition

voltage during abnormal condition

constantly the electrical quantities which differ during normal and abnormal conditions

none of the above

Oil circuit breakers

Air blast circuit breakers

Minimum oil circuit breakers

All of the above

Inductance

Capacitance

Resistance

Reactance

interception

interception and conduction

interception, conduction and dissipation

interception, conduction, dissipation and reflection E. none of the above

constant for all distances

lower than that of if fault occurs away from the relay

higher than that of if fault occurs away from the relay

none of the above