“[Particle Count] covers the determination of particle concentration and particle size distribution in mineral insulating oil. It is suitable for testing oils having a viscosity of 6 to 20 mm2/s at 40°C.”
(Quote from ASTM D6786-2015)
What method is used to analyze the sample?
ASTM D6786
IEC 60970
How do you interpret the results?
ISO 4406-2021
What do the results indicate?
“Particles in insulating oil can have a detrimental effect on the dielectric properties of the fluid, depending on the size, concentration, and nature of the particles. The source of these particles can be external contaminants, oil degradation by- products, or internal materials such as metals, carbon, or cellulose fibers. Particle counts provide a general degree of contamination level and may be useful in assessing the condition of specific types of electrical equipment. Particle counts can also be used to determine filtering effectiveness when processing oil. If more specific knowledge of the nature of the particles is needed, other tests such as metals analysis or fiber identification and counting must be performed.” (Quote from ASTM D6786-2015)