What Is LT Line, HT line, and Transmission Line, Definition, Voltage

Hello Guys, welcome back to my blog, in this article I will discuss the LT line, HT line, and transmission line, what is lt (low tension) line, what is ht (high tension) line, and what is a transmission line.

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LT Line, HT line, and Transmission Line

Transmission lines, Ht lines, and Lt lines are nothing but Conductors used to transmit Electricity from generating station to Consumers. Usually, ACSR conductors are used to transmit Electricity, in ACSR conductors there are different types of conductors ( Rabbit, squirrel, Drake, etc )

Transmission lines, HT lines, and LT lines are used to transmit electricity but they are used at different stages to transmit different voltages (440 V, 11 KV, 33 KV, 110 KV ).

Transmission Line

Transmission lines are nothing but Conductors used to transmit Electricity from generating stations to Sub-stations. In Transmission lines, the conductors are supported by steel Structures. Transmission towers are erected outside the cities because they carry high voltage which will be harmful to both Birds and Human beings. In transmission lines, ground clearance should be more.

Classification of Transmission tower

(01). Single Circuit Transmission tower

(02). Double Circuit Transmission tower

(03). Four Circuit Transmission tower

Transmission line Voltage – 66 KV, 110 KV, 220 KV, 400 KV, 745 KV.

HT(High Tension) Line

The Conductors used to transmit Electricity from Sub-stations to Distribution Transformer ( Double Pole Structure ) are known as HT Lines. HT Lines are erected only on main roads of Cities or villages. In the Sub-station voltage of Transmission, the line is step-down to 11KV, this 11KV voltage is transmitted to Distribution Transformer ( Double Pole Structure ) by HT lines. At Double Pole Structure, the distribution transformer is used which will step down the 11kv voltage to 440 volts. HT line conductors are supported by the RCC pole as shown in the above figure.

In HT lines we can see only three lines nothing but three phases three conductors but the neutral wire is absent because in the sub-station neutral wire coming from Power Transformer is grounded.

LT (Low Tension) Lines

The Conductors used to transmit Electricity from Double Pole Structure ( Distribution Transformer ) to Consumers are known as LT lines. LT lines are drawn in every street and area. The 11 KV voltage is fed to DP Structure by HT lines, in DP Structure distribution transformer is used which will step down the voltage from 11 kV to 440 volts (for 3 Phase) 230 volts (for single Phase), this 440 V is carried by LT lines. In the LT line four wires are used, three conductors for three-phase ( RYB ), and one conductor for Neutral.

At last, the Electricity is supplied to the meter board by using Overhead Service Mains and Underground Service Mains.

I hope this article may help you all a lot. Thank you for reading. If you have any doubts related to this article “LT line, HT line, and Transmission Line”, then comment below in the comment box.

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Chetan Shidling

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