Standardized electrostatic charging tendency measurements in terms of temperature

To avoid the electrostatic hazards inside the large power oil-immersed transformers, it is necessary to have at one´s disposal reliable tools for checking and servicing. The Electrostatic Charging Tendency (ECT) Minitester is amongst the most commonly used. An enhanced device is proposed and put to the test. More, another protocol and set-up improvement is perfected in order to measure the oil Electrostatic Charging Tendency in terms of the temperature and to provide additional information about the electrostatic hazards when the large transformer runs under standard conditions.