GAIL (India) Limited

245.3.2 Installation: The transformer shall be installed as per the installation manual provided by thetransformer manufacturer. The installation shall also conform to the relevant IS and IE rules. After thecompletion of the erection of the transformer it shall be ensured that the transformer wheels are suitablylocked to prevent accidental movement of transformer. HT and LT cabling LT bus duct shall be earnedout as detailed in the schedule and working drawing. The transformer neutral and body shall be earthed asdetailed in the drawing. The breather shall be cleaned and filled with oil and silica gel.5.3.3 Testing and commissioning: The following test shall be conducted on the transformer prior iscommissioning:i) Insulating resistance of the winding between phases and between individual phases and earth on both HVand LV sides and also between HV and LV windingsii) Winding resistanceiii) Di-electric strength of transformer oiliv) Voltage ratio test at all tap positionsv) Polarity testAfter commissioning of the transformer, the MV sides voltage shall be measured at different tap positions.The transformer shall be kept on no load for 24 hours, and shall be ascertained that there is no unduetemperature rise before loading the transformer.