2.This paper covers such important problems as earth connection,ups,super shielded transformer,earth free of power system and computer room, and methods to deal with them are also put forward.
3.and 45# transformer oils were produced from the distillate of highly paraffinic Shenbei crude by isopropanol/urea dewaxing. Dewaxing was operated at room temperature and atmospheric pressure, freezing points lower than -25 ℃ and -45 ℃ dewaxed oils and the wax contained more than 90% normal paraffins were obtained. The flash point, viscosity, acid number and electric property of the dewaxed oils after treating met the national standards of 25# and 45# transformer oils.