TTPS ES Circle EM I Capital Maintenance of Transformers Generator Bus duct H2 gas purging and filling works in Unit I during the capital overhauling for the year 2025 2026

Charges for Purging of H2 gas in TG casing,

After completion of overhaul purging out of air by Co2 and Co2 by hydrogen to the required pressure as decide by site engineer.

Charges for maintenance works in HV Condenser Bushings of 84 MVA Three phase Generator Transformer and 216 KV LAS: Disconnection of HV jumper connections in Generator Transformers R,Y and B phases, support insulators, 216 kv lightning arrestors and neutral grounding CT, cleaning of HV condenser bushings, support insulators, neutral bushings, 216 kv LAS, connecting leads for MRT testing, restoring of all jumper connections and tightness checking.

Cleaning of Neutral earth resistance of UAT A & B, UST, SST, Generator neutral grounding reactor and Generator neutral grounding Transformer. Assisting for testing, meggering and measuring resistance value.

Charges for maintenance works in 230 KV strung bus of 84 MVA three phase Generator Transformer: Transportation of ladder from switch yard I, Tightness checking at the joints of jumpers from Generator Transformers, Support insulator and LAS to strung bus, checking the conditions of aluminum clamps and replacing if needed.

Opening the manholes in UAT A & B, disconnection of primary links at both transformers, cleaning the primary terminal bushings. Opening the LV chamber of UAT A & B, Cleaning the LV Bushings and bus bars, Tightness checking of LV side cables, After completion of work closing the LV chamber. Assisting during testing. Restoration after completion of the works.

SST II & UST II: Opening the HV side adopter box cover of the transformer, terminal tightness checking,and cleaning changing of the gasket for top cover and closing. Tightness checking at LV side cables, arrestting of oil leaks if any, assisting for meggering and Buchholz relay testing, external cleaning. Restoration after completion of the works.

Excitation transformer Disconnection of the bus links from HV/LV side, cleaning the transformer, assisting for testing and meggering, LV side cable tightness checking. Restoration of the links after completion of the works.

BUS DUCT PHASE SIDE Opening the manhole in the phase side bus duct and disconnection of the horizontal bus bars in all the three phases. Assisting for testing, meggering. Restoration of the bus bar links after completion of the works and closing the manholes.

BUS DUCT NEUTRAL SIDE Opening the manhole in neutral bus duct and disconnection of the vertical bus bars for all the three phases and cleaning. Assisting for testing, meggering. Restoration of the links and closing of the man holes after completion of the works.

Bus duct man hole opening at all the phases, cleaning of the buses from Generator Phase side to Generator transformer both out side and inside, tightness checking of all the joints, cleaning of the supporting insulators, LAVT Cubicles assisting for testing and meggering. Restoration of covers after completion of the works.

Cleaning and tightness checking of LAVT cubicles, bus bars, dismantling of 3 Nos. 18 KV lightning arrestors from LAVT cubicle Transporting to MRT Lab for testing & restoration after testing.

Generator Transformer cleaning: Cleaning of the Generator Transformer bushings of R, Y & B Phases and other supporting insulators, lightning arrestors and checking of oil leaks, cleaning the top surface of the transformers, tightness checking of the take off jumper joints.

Charges for maintenance works in 84 MVA Single phase Generator Transformer: Opening of LV turret covers in Single phase Generator transformers (3 Nos.) R,Y and B phases, disconnection of flexible links in 24 kv bus duct to GT LV side, cleaning the transformer, meggering, topping up of transformer oil if needed and assisting for testing of bucholz relay, surge relay and PRV, restoration of LV side links after completion of works.

Labour charges for H2 gas Regenerative type drier cleaning both A & B chamber internal cleaning, gasket changing work.

Charges for cleaning of Single phase Generator Transformer and its radiators, UAT A,UAT B and its radiators, UST, SST with sodakaram and water during completion of overhauling works.