What is the difference between rulling span and wind span of of an Over Head Transmission Line?

1632

My question is whether bellow formula is correct to find bus size for 46kA for 0.5 second & what is RT in bellow formula. formula to calculate the size of busbar to withstand the thermal stresses due to currents with duration of 0.2 sec to 5 sec. Sp = RT( I x I x t) / K Where Sp – is the cross sectional area of bus bar in millimeters. I -    is the value of AC fault current. t -    is the operating time of disconnecting device in seconds. K –  is the factor depending on the material of the conductor, insulation and initial and final temperature. Value of ‘k’ for copper is 143.

1285

what is the min and max ohmic resistance for the earthing rod installed for lighting poles for street light network

2726

How can get elongation of 2 k.G aluminium, if elongated aluminium dia is 2.5 mm?

1605

how generator load test is conducted?what are the steps?

965

how to meas-our losses for L.T & H.T

1512

How do we calculate the maximum amount of current in a 300 SQ.MM cable ?

1430

How many devices can be connected in one zone of FACP

1617

Single line diagrams for star to delta and DOL starters.

1624

The slip during plugging operation is given by= A 1-s B 2+s C 1+s D 2-s

2182

How to know the following data of synchronous generator 1. D-Axis Unsaturated Reactance 2. D-Axis Unsaturated Transient Reactance 3. D-Axis Unsaturated Sub - Transient Reactance

1304

How much inductance or resistance require as a starter in series with induction motor of specific capacity(e.g. 5 hp) ? What is formula for it ?

1317

what is the current density of copper & alluminium.

1339

What is the universal motor?

479

explain the process of commutation in a dc machine. Explain what are inter-poles and why they are required in a dc machine.

486