Prior to carrying out electrical tests, a visual check of the transformer should be carried out paying particular attention to the following points
• Equipment and cables are undamaged
• Correct execution of the cable gland/sealing end
• Firm cable termination/terminal connection and ferrule
• Check name Plate data for correctness in accordance with approved drawings
• Check all components are installed
• Check for any damages, oil leakage, defectives
• Check all groundings are securely connected "at least two points
• Check that piping for Buchholz relay has proper slope and direction towards the conservator
• Check that the Inlet &Outlet valves of the Buchholz relay are OPEN
• Check that the valves for the Protective relay of OLTC are OPEN
• Check all valves between the main tank and radiator are OPEN
• Check the color and quantity of Silica gel in the breather and oil pot level
• Check labeling of both High & Low Voltage Bushings
• Check labeling of all Aux. Devices and cables in accordance with drawings
• Check proper Installation of all Aux. Devices
• Check Oil level in the conservator and Bushings.
• Check the tightness of all wiring
• Check installation of Gas Monitoring Unit "CALISTO" , sample valves are open
• Check installation of On Load Tap Changer
• Records from the impact recorder shall be checked once the transformer is in position for
any abnormalities caused during transportation, if the recorder is electronic then stored data
shall be sent to the vendor for analysis (this is part of the erection activity)
• Tightness of all bolted connections to be checked and torque according to the manufacture
recommendation (this is part of the erection activity)
• Horizontal and vertical clearance of live parts to adjacent ground parts to shall be checked
and confirm to the standard (this is part of the erection activity)
• Bushing and Neutral CTs shall be checked for damages to connections