IEC 61868:1998

Specifies a procedure for the determination of the kinematic viscosity of mineral insulating oils, both transparent and opaque, at very low temperatures, after a cold soaking period of at least 20 h, by measuring the time for a volume of liquid to flow under gravity throught a calibrated glass capillary viscometer. Applies at all temperatures to both Newtonian and non-Newtonian liquids having viscosities of up to 20 000 mm2/s.