1 dielectric: also known as insulating materials, referred to as insulation, is one of the most widely used materials in electrical engineering.

2 insulation resistance: plus DC voltage in the dielectric, after a certain time of polarization process, the leakage current through the dielectric corresponding to the resistance of the insulation resistance.

3 absorption ratio: in the same test, the insulation resistance value of 60s is compared with that of the insulation resistance value of 15s.

4 polarization index: in the same test, the insulation resistance value of 10min is compared with that of the insulation resistance value of 1min.

5 dielectric loss: in the applied voltage, a part of the dielectric can be converted into heat energy, which is called the dielectric loss.

6 resistive current: the loss of the medium can be used with an ideal capacitor and an effective resistance of the parallel circuit, said the current resistance through the resistance of the current resistance.

7 capacitive current: the loss of the medium can be used with an ideal capacitor and an effective resistance of the parallel circuit, said capacitive current through the capacitor.

8 full current: a lossy dielectric can be expressed in parallel with an ideal capacitor and an effective resistance, the capacitance of the capacitive current and the resistance of the resistance of the current phase of the amount and said the full current.

9 dielectric loss angle: the angle between the total current and the capacitive current in the dielectric (usually expressed), which is called the dielectric loss angle.

10 on line measurement: on the operating voltage of the equipment, the use of special equipment, by the personnel involved in the measurement.

11 on line monitoring: in the operation of the equipment does not affect the condition, the equipment status of continuous or regular monitoring, usually carried out automatically.

12 state maintenance: from the United States Ge Corp proposed to take time as the basis for the development of maintenance to the equipment operating conditions as the basis of the maintenance mode.

13 preventive test: in order to discover the hidden danger of equipment operation, prevent the occurrence of accident or equipment damage, the equipment inspection, testing or monitoring, also including the oil sample or gas sample test.

14. The ratio: high voltage side of the transformer winding and the low-voltage side winding turns ratio, said ratio, approximate available high pressure and low pressure sides rated voltage ratio.

15 volt ampere characteristics: the voltage at both ends of the electrical equipment or components and the relationship between the current through the current characteristics called the volt ampere characteristics.