TRANSFORMER OILS
Detail Description
HP TRANSFORMER OIL I is inhibited type transformer oil meeting IS:12463. Inhibited transformer oils can extend the service life of transformer oil.
It also meets IS:335-2018 TYPE II INHIBITED.
Physico-chemical properties
| Test Method | Typical | |
| Appearance | A representative sample of the oil shall be examined in a 100 mm thick layer at 27ºC | Clear and transparent and free from suspended matter or sediments |
| Density at 29.5ºC, g/cc | IS 1448 [P : 16] : 1990 | 0.8279 |
| Kinematic viscosity, | IS 1448 [P : 25] : 1976 | |
| at 27ºC | 16.46 | |
| at 40ºC | 11.76 | |
| Interfacial tension at 27ºC, | IS 6104 : 1971 | 0.044 |
| Flash point Pensky-Marten (closed), ºC | IS 1448 [P : 21] : 1992 | 148 |
| Pour point, ºC | IS 1448 [P : 10] : 1970 | -18 |
| Neutralization value | ||
| a) Total acidity, | IS 1448 [P : 2] : 1967 | Nil |
| b) Inorganic acidity/alkalinity | Nil | |
| Corrosive sulphur | Annex B of IS 335 – 1993 | Non Corrosive |
| Electric strength | 72 | |
| (breakdown voltage) | IS 6792 : 1992 | |
| a) New unfiltered oil, | ||
| b) After filtration, min | Note 2 | |
| Dielectric dissipation factor (tan δ) at 90ºC, | IS 6262 : 1971 | 0.00025/2.05 DC |
| Specific resistance (resistivity) | IS 6103 : 1971 | |
| a) At 90ºC, | 750 × 1012 ohm-cm | |
| b) At 27ºC, | 7650 × 1012 ohm-cm | |
| Oxidation stability | IS 12422 – 1988 | |
| a) Neutralization value after oxidation, | Nil | |
| b) Total sludge, after oxidation, | Nil | |
| Oxidation stability (Rotating Bomb test), minutes | IS 12958 – 1990 | 210 |
| Oxidation inhibitor, percent by, wt | IS 13631 – 1993 | 0.26 |
| Water content, ppm | IS 13567 – 1992 | 9 |