MID/AN/102

1. Overhauling / Servicing with repairs to 2500 KVA Regulating Unit of H.T Automatic Voltage Regulator by the way of drawing of V.C.B from the breaker chamber, isolating all the three isolating units after disconnecting the power cables from the main H.T transformer then disconnecting all cables between the main transformer and regulating unit, auxiliary control circuit, wiring of pilot motor box. Dismantling of top tank cover, taking out of hand wheel after disengaging the motor driver from the regulator, disconnecting the flexible cable from the tank terminal board. Extracting out of coils of all three phases with the help of Crane. Replacing the damaged / worn out components i.e P.C.B Relay – 01 Nos., Carbon Rollers – 48 Nos. which do not rotate smoothly and are damaged /worn-out, Tag and tail assembly with sleeves – 48 Nos. Checking of the complete roller assembly as it run freely on the spindle and carbon brushes on the coils with a minimum play, replacing the rotating plates locking with screw and maintaining the brush lead position. Lifting the complete unit and lowering it in the main tank of the regulating unit with the help of crane/JCB in such a way that no part/component is disturbed/damaged. Refilling of oil after dehydration with providing of additional oil of approx. 65Ltrs. for topping.Making of connections of flexible cables, refitting of tank cover, motor box after replacing the gaskets, insulator with spreads, nuts and bolts, making connections of all the control circuit wiring. Also drawing out of oil from the main H.T transformer of A.V.R unit, disconnecting of all the connections of control circuit, dismantling of explosion unit, conservation tank and top lid of the tank. Cleaning of insulator, examining them carefully for small fractures and replacing them where ever found necessary, refitting top cover, explosion unit and conservation tank, dehydration and filling of oil with topping up with additional oil up to the required level (up to approx 55 ltrs.). Job includes replacement of wiring of the control panel used for raising and lowering the voltage then making all the connections of the control circuit wiring, main input and output power cables, interconnection cables of main transformer and regulating unit. Complete job includes cost of material, additional oil reqd. for topping, hire charges for machinery installed during execution of the job for regulating unit and main H.T transformer. Complete Job.