155. Transmission lines are classified as short, medium and long depending on the
A. length of line
B. charging current or no load current
C. capacitance of line
D. both A and B above
156. A series compensated transmission line has better
A. transient stability
B. steady state stability
C. short circuit capacity
D. reactive capacity
157. Reactive power can be injected into a trans-mission line by using
A. series capacitors
B. shunt capacitors and reactors
C. synchronous capacitors
D. all of these
158. The earthing switch is generally installed on
A. main board
B. isolator frame
C. circuit breaker frame
D. none of the above
159. Surge impedance of a single circuit transmission line is 400L2. The surge impedance of a double circuit line of the same type will be
A. 200 W
B. 400 W
C. 800 W
D. 1200 W
160. Corona is observed on
A. a.c. transmission lines only
B. d.c. transmission lines only
C. both a.c. and d.c. transmission lines
D. none of these
161. An advantage of corona on transmission lines is that
A. it minimizes power loss
B. it reflects electrical surges
C. it works as a surge modifier during overloads
D. none of these
Page 23 of 54