TCS Interview Questions and Answers

The cost of one km of new OHE supply and installation varies depending on several factors.

• The cost can vary based on the location and terrain of the installation site.

• The type and quality of materials used can also impact the cost.

• Labor costs, including skilled technicians and engineers, need to be considered.

• Additional costs may include equipment rental, transportation, and permits.

• Examples of factors affecting cost: distance from the power source, ground conditions, accessi...read more

The rating of LA used at 25kv side in switching station and Traction sub station depends on the specific requirements and design of the stations.

• The rating of LA (Lightning Arrester) at the 25kv side in switching station and Traction sub station is determined based on the voltage level and the expected lightning surge levels.

• The LA rating is typically specified in terms of voltage withstand capability and energy absorption capacity.

• The rating of LA may vary depending on the s...read more

Relay testing by primary and secondary injection involves injecting current into the relay to test its functionality.

• Primary injection testing involves injecting a high current directly into the relay to simulate a fault condition.

• Secondary injection testing involves injecting a low current through the relay's input terminals to test its response.

• Primary injection testing is more accurate but requires specialized equipment, while secondary injection testing is simpler and mor...read more

Impedance is the opposition to the flow of alternating current in a transformer, while efficiency is the ratio of output power to input power.

• Impedance is the total opposition to the flow of alternating current in a transformer, including resistance and reactance.

• Efficiency of a transformer is the ratio of output power to input power, expressed as a percentage.

• Higher impedance in a transformer can lead to voltage drops and inefficiencies.

• Efficiency can be improved by using hi...read more

Contact and catenary configuration involves the arrangement of overhead wires and supports for electric trains.

• Contact wire is typically made of copper or aluminum and carries the electric current for the train

• Catenary wire is used to support the contact wire and is usually made of steel

• The contact wire is suspended from the catenary wire using droppers or hangers

• The catenary wire is supported by overhead line equipment such as masts, brackets, and cantilevers

• Proper tensionin...read more

Using 2*25 over 1*25 OHE provides redundancy and reliability in case of failures.

• 2*25 OHE provides redundancy in case of a single line failure

• 2*25 OHE allows for maintenance on one line while the other remains operational

• 2*25 OHE increases reliability and reduces downtime compared to 1*25 OHE