Question

Line that connects the distributor conductor at the nearest pole to the consumer's end is

• A. Secondary transmission lines
• B. Service mains
• C. Primary transmission lines
• D. Secondary distribution lines

Hint:

(J) Electrical Power System Stages: Generation $\rightarrow$ Transmission (Primary & Secondary) $\rightarrow$ Distribution (Primary & Secondary) $\rightarrow$ Service Connection.
(K) \textbf{Distributors (Secondary Distribution Lines):} Low-voltage lines in streets/areas from which consumers are supplied.
(L) \textbf{Service Mains (Service Line / Service Drop):} The final overhead or underground line connecting the distributor to the consumer's premises (meter).
(M) Transmission lines operate at much higher voltages for bulk power transfer.

Answer 1

The Correct Option is B

Electrical power distribution systems consist of several stages:
(A) Generation: Power is produced at generating stations.
(B) Transmission: High voltage transmission lines carry bulk power over long distances from generating stations to main substations.
(C) Primary transmission lines: Highest voltages (e.g., 220 kV, 400 kV, 765 kV).
(D) Secondary transmission lines: Lower high voltages (e.g., 66 kV, 110 kV, 132 kV), connecting main substations to area substations.
(E) Distribution: From area substations, power is distributed to consumers at lower voltages.
(F) Primary distribution lines: Medium voltages (e.g., 11 kV, 33 kV), feeding distribution transformers.
(G) Secondary distribution lines (Distributors): Low voltages (e.g., 400V three-phase, 230V single-phase in India), running along streets or areas, from which consumers are supplied. These are the "distributor conductors at the nearest pole" mentioned.
(H) Service Connection:
(I) Service mains (Service line / Service drop): The line that connects the secondary distribution line (distributor) at the nearest pole or underground junction to the consumer's premises (specifically, to the consumer's energy meter or main switch). This is the final link in the power supply chain to the end-user. The question asks for the line connecting the "distributor conductor at the nearest pole to the consumer's end". This accurately describes the Service mains (or service line). Let's evaluate the options:
(a) Secondary transmission lines: These are high voltage lines, part of bulk power transmission, not the final connection to consumer.
(b) Service mains: Correct. This is the line from the local distributor to the consumer's building.
(c) Primary transmission lines: These are very high voltage lines for long-distance bulk power transmission.
(d) Secondary distribution lines (Distributors): These are the local low-voltage lines running in a neighborhood, from which service mains tap off to individual consumers. The question asks for the line *from* the distributor *to* the consumer. Therefore, the correct term is Service mains. \[ \boxed{\text{Service mains}} \]