MID/J/58

Disconnecting the 250 KVA electric transformer from the input and output connections, from HT and LT side after ensuring the shutdown from the concern sub division of PDD. Lowering the transformer from the platform and then loading the electric transformer using manual labour & hydra crane in the mechanical transport for shifting it to workshop for repairs. Unloading at workshop and then dismantling the 250 KVA transformer, at workshop by way of extracting out the damaged HT coils & LT coils, LT bushes-03 no., HT bushes-03 no., damaged insulator, rubber gasket, nuts and bolts. Complete rewinding of 3 no. HT leg coil assembly with aluminum wire of appropriate gauge & reconditioning of 3 no. LT leg coils which includes proper insulation. Keeping the coil assembly in the oven to make moisture free so that requisite megger value is achieved. Providing and fitting of LT and HT bush rod sets, new insulator, rubber gasket, new copper nuts and bolts and other necessary items. Cleaning the sump/container of transformer with appropriate chemical agent to remove all carbon deposit. Lowering the assembled coil assembly in the sump of the transformer and then securing it with the body of the transformer. Filling the transformer oil in the sump after giving heat treatment to make it moisture free and topping up with 200 liters fresh transformer oil. Refitting the top cover by providing and fitting requisite gasket, nuts and bolts of appropriate sizes. Testing the continuity of each phase and securing all connections. Shifting the repaired electric transformer back to site i.e. LIS Ismailpur in similar manner, unloading and installing at transformer hoisting channel/platform with the help of hydra crane and skilled manual labour. The job also involves providing and fitting of drop out set (complete) along with allied material after extracting out the old damaged set. Connecting of HT supply by providing and fitting of thimbles along with aluminum wire of appropriate gauge/size. Allowing the transformer to charge at no load and then connecting the LT supply and testing the transformer on full load at site. Supplying, installation, testing, and commissioning of a 400A, 415V, 50Hz, 3-phase standard make main switch unit enclosed in a robust sheet-steel enclosure complete with required HRC fuse links / trip units, handle mechanism, and interlocks; fabrication and erection of an MS channel/angle iron mounting frame (finished with anti-rust primer and enamel paint) firmly anchored to the wall; making incoming and outgoing cable terminations using existing cables along with along with thimbles, nuts, bolts, and washers, Check for continuity, phase alignment, contact resistance check, and full-load trial run at site; the complete job inclusive of all skilled labour, tools, hardware, testing equipment. The complete job includes rebate on old parts, cost of material, labour charges, loading & unloading, to & fro carriage, testing and installation and hire charges of the hydra crane used during the execution of job.

Rebate on Old Parts