15/MID/AN

Charges for loading of 2.5 MVA capacity, HT Electric Transformer 33/6.6 kV at site with the help of suitable capacity Hydra Crane and trailer truck suitable to maneuver at site and transport the same through road to firm’s works, unloading, loading at firm’s works after repairs, dispatch and unloading/stacking at required platform at site, making of electric connections on HV Side & LV side by way of cleaning of bus-bars, providing and fitting of new thimbles, nuts, bolts and washers. Making of earth connections after testing of earth resistance value. Field testing of transformer for all connected functional parameters on load as well on no load conditions, checking for noise/humming, temperature rise etc. Complete job including the cost of material, hire charges of machinery/tools & tackles and labour charges.

Repairs to APEX make 2.5 MVA capacity, three phase, 33KV/6.6KV, ONAN cooling, Vector group Dyn 11, no load voltage (HV-33KV & LV-6.6 KV), current on HV side- 43.738 Amperes & 218.7 Amperes on LV side, Maximum temperature rise in oil 50º C, frequency 50 HZ, Impedance Voltage 6.556% installed at electric substation of LIS Ranjan. The job includes opening of top cover, extraction of transformer assembly out of the housing, Complete dismantling of transformer assembly & allied parts and draining out of insulating oil safely into barrels. Providing & making of new coils out of EC grade copper with insulation HT coils (3-legs@228 Kg per leg), reconditioning of LT coils (3-legs@157 kg per leg) in place of damaged coils, assembling & making of connections by new EC grade copper of new pre-heated coils on HV & LV side as well. Assembly of core, core- coil assembly. Providing and in laying in position of tapping connections by way of brazing with silver brazing rods including properly insulated tap leads dressed with insulation paper. Baking of re-wound transformer assembly in heating chamber till Specified/ proper IR value is achieved. Cleaning of transformer tank from out -side & in- side as well to make it free from slag, dirt, and other unwanted deposits/ suspensions. In-side painting of transformer tank with hot oil resistant paint. Boxing up of Transformer with re-wound transformer assembly and complete connected accessories by providing and fitting of new HT bushings assembly (3 No.), LT Bushings assembly (3 No.), LT terminal plate, gaskets, fasteners, and connected sundries. Out-side painting of transformer tank with two coats of red oxide followed by two coats of synthetic enamel after proper surface preparation. Providing & fitting of new breather assembly including silica gel and oil drain valve in place of old unserviceable ones. Filling of new oil in transformer (≈2200 ltrs) with the required BDV value and Di- electric strength upto specified mark inside conservator. Shop testing of transformer for permissible magnitudes of all connected parameters. Complete job including the cost of material and labour charges.

Servicing of oil type OLTC (on load tapping changer) by way of cleaning of contacts and pits if any, oil sludge removal, adjustment of springs, checking of motor drive operation, wiring, insulation rods for its proper mechanical & electrical strength and separation/barrier plates. Change of oil complete by ≈250 ltrs. After cleaning of contacts, the contact resistance to be checked to ensure proper cleaning/contact. All lugs/crimping at OLTC taps to be checked and re-crimped. Replacement of unserviceable moving contacts, oil surge relay and papers of all tapping leads of reputed quality. Complete job including cost of material, labour and testing.

Rebate on copper scrap ( in Rs. per kg)

Rebate on old unserviceable T/oil ( in Rs. Per ltrs)

NATIONAL ELECTRO-MECH COMPANY

PERFECT ELECTRICAL WORKS