Recent questions tagged overhead

Description : Differentiate between overhead transmission and underground transmission.

Last Answer : Points Overhead line  Underground cable Capital cost  Less More Erecting cost  Less More Time require for completion of work Less More Flexibility More ... Space consumed Space consumed  No space consumed Appearance Not good  Very good 

Description : State properties of conductor material used for overhead conductor. 

Last Answer : Following are the properties of conductor material:-   1. High conductivity :- Material should have high conductivity 2. High mechanical strength:- Material should have sufficiently high mechanical strength ... available & less costly. 9. Scrap Value: - Material should have high scrap value. 

Description : Why are overhead transmission lines not insulated?

Last Answer : Insulators are useful to help separate electrical conductors when they come into physical contact. Overhead Transmission Lines Are Not Insulated: The overhead transmission line is carrying extreme high voltage and ... a whole lot of thick insulation to absorb the heat produced by such high voltage.

Description : Why underground service connections are service connections are costly than overhead service connection

Last Answer : Reason: Underground service connection is given by underground cable. This cable is costly than bare conductor. Sometimes cable trench is required for cable laying, which requires additional cost. So underground service connections are costly than overhead service connection.

Description : Define service connection and state types connection and state types of overhead service connection

Last Answer : Service Connection:- It is the input conductor or wire which is carried out from supply company (authorities) pole to consumers' main board or premises. Types of overhead service ...  1. Overhead service connection with Bare conductor 2. Overhead service connection with weather proof cable  

Description : A minimum clearance of 6.3 m to ground is required for overhead lines when operating voltages are :  (A) less than 66 kV (B) lie between 66 kV and 110 kV (C) more than 165 kV (D) lie between 110 kV and 165 kV

Last Answer : A minimum clearance of 6.3 m to ground is required for overhead lines when operating voltages are : lie between 66 kV and 110 kV

Description : lf a travelling-wave travelling along a loss-less overhead line does not result in any reflection after it has reached the far end, then the far end of the line is

Last Answer : lf a travelling-wave travelling along a loss-less overhead line does not result in any reflection after it has reached the far end, then the far end of the line is terminated into a resistance equal to surge impedance of the line

Last Answer : Overhead lines for power supply to tramcars are at a minimum height of 10 m.

Last Answer : Overhead system can be designed for operation up to 400 kV.

Description : Why ACSR conductor is used for overhead lines?

Last Answer : It has high tensile strength