In the ordinary work, the power workers often need to test the zero value of the insulator to test the voltage distribution value of the insulator string, so they need to use the insulator zero value tester. In the process of testing, the equipment has certain standards for the test results. This paper will give you a brief introduction of the use standards of the insulator zero value tester.
I. measure the voltage distribution (or spark gap):
1. The voltage value of the tested insulator is less than 50% of the standard value (see Table 1 and table 2 for the standard value of voltage distribution), which is judged as degraded insulator;
2. The measured voltage value is more than 50% of the predetermined standard value of the insulator, which is significantly lower than the two adjacent sides judged as the qualified voltage value of the deteriorated insulator.
3. The insulator does not discharge under the specified spark gap distance and discharge voltage, which belongs to the deteriorated insulator.
II. Measurement of insulation resistance:
1. Voltage class 500 kV: the insulator insulation resistance is less than 500 m Ω, which is determined as the deterioration of the insulator;
2. 500kV voltage level: if the insulation resistance of the insulator is lower than 300m Ω, it is judged as deteriorated insulator.
III. power frequency withstand voltage test
The insulator with mechanical damage load of 60kn-530kn shall bear the dry power frequency withstand voltage of 60kV for one minute, and the insulator with coil diameter and large anti pollution type shall bear the dry power frequency flashover voltage corresponding to the common insulator, and the insulator without deterioration is not allowed.
Four, patrol inspection
The area of the glaze defect does not meet the requirements of gb772, and the porcelain parts are judged to be degraded insulator, such as cracking, breaking, steel foot, cement loosening, etc.
V. mechanical strength test
When judging the mechanical strength of the deteriorated insulator at 85% of the rated load of organic damage
The use standard of insulator zero value tester has certain guiding significance for the use of the equipment. When using the equipment, power workers need to see the test results according to the above test standards.
