RECOMMENDED LIMITS FOR MINERAL INSULATING OILS AFTER INITIAL FILLING OF ELECTRIC EQUIPMENT, BEFORE ENERGIZING- IEC 60422:2005, TABLE 3

Test

Limits

Voltage(HV), kV

<72.5

72.5 to 170

>170

Breakdown Voltage (kV/cm)

>220

>260

>260

Water Content (mg/g)

<20

<10

<10

Neutralisation Number (mgKOH/g)

<0.03

<0.03

<0.03

Interfacial Tension (mN/m)

>35

>35

>35

Dielectric Dissipation Factor - tg δ

<0.015

<0.015

<0.010

Oxidation Stability

Acc. to IEC60296 (for unused oils)

Particles (ISO4406)

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9/6 to 10/7