For additional accuracy, an oil-specific calculation model can be used in HMP378F for mineral transformer oils. A specific model is always needed for other transformer oil/fluid types. Note that the calculation is only supported for stable dielectric fluids.
For oil-specific coefficients, an oil sample has to be sent to Vaisala for modeling. As a result, the specific coefficients (A and B: see formula in HMP378F calculation model with average oil coefficients) for the oil are determined by Vaisala. Using these coefficients increases measurement accuracy.
You can configure the determined coefficients of the oil into use with Insight PC software, or contact Vaisala about setting the coefficients. For configuration instructions, see Configuring calculation coefficients.