Polarization Index is ratio of Insulation Resistance after 10 minutes (When Insulation Resistance value becomes stable) and Insulation Resistance Value Measured after 1 Minute.
Polarization Index Indicates Dryness of Insulation of Any electrical equipment.
So. Polarization Index= (10 Min. I.R. Value)/(1 Min. I.R. Value).
Polarization Index must be more than 1.25. If, P.I. is less than 1.25 than it shows poor Condition of Insulation.
One, another way to check insulation Condition is Tan-Delta test.
Width of maximum right of way permitted as per forest conservation act ‘1980 and its subsequent amendment dated 25 th October, 1992, are as per Table 1. Researches are being carried out for further optimizing the Right of Way. Guidelines of forest environmental rules shall be followed to avoid excessive tree cutting i.e. all the trees should be cut from root level in the 3 m corridor below each line conductor / earth wires. In the balance corridor, trees branches are only to be lopped to attain the specified clearance as per Table 1. Table 1 – Guidelines for Right of Way as per forest conservations act 1980 and subsequent amendment dated 25 th October, 1992 Line voltage (kV) 66 110 132 220 400 500 HVDC 765 Row width (Meter) 18 22 27 35 52 52 85 Electrical clearance: Electrical clearance while power lines crossing each other. In case of power line crossings, minimum clearance between lowest conductor of line and ground wire / top conductor of ...