The main problems in the operation of zinc oxide arrester tester

1. The main problems in the operation of zinc oxide arresters

1. The zinc oxide arrester has long-term system voltage and current flow due to the cancellation of the series gap. The active component of the current generates heat on the valve plate, which induces changes in the volt-ampere characteristics. The result of long-term action will cause the valve plate to age and even thermal breakdown.

2. When the zinc oxide arrester is used by impulse voltage, the valve plate will also age under the action of impulse voltage energy.

3. Moisture inside the zinc oxide arrester or poor insulation performance will increase the power frequency current, increase the power consumption, and cause internal discharge in severe cases.

4. The zinc oxide arrester is polluted by rain, snow, condensation or dust. Due to the difference of internal and external electricity release, there is a relatively potential difference between the internal valve plate and the external porcelain sleeve, resulting in radial discharge.

Two, zinc oxide arrester characteristic tester The task to be completed by this instrument

To judge whether the valve of the zinc oxide arrester is aging or damp, usually observe the change of the leakage current that flows through the zinc oxide valve during normal operation, that is, observe whether the resistance increases as the judgment basis.

Three, zinc oxide arrester characteristics tester This tester is mainly for the following aspects

1. Thermal breakdown of zinc oxide arrester

The reason for the thermal breakdown of the zinc oxide arrester generator caused by the zinc oxide arrester characteristic tester is that its heating power is greater than the heat dissipation power. The heating power of the zinc oxide valve plate depends on the current and voltage (current is the active component of the current flowing through the valve plate).

2. Moisture inside the zinc oxide arrester

If the seal is not tight, it will cause moisture inside the arrester or moisture ingress during installation, which will increase the total current of the arrester under voltage. When the zinc oxide arrester characteristic tester is damp to a certain extent, discharge will occur along the surface of the zinc oxide valve plate or the inner wall of the porcelain sleeve, causing the arrester to explode.

The increase in the total current caused by the damp of the zinc oxide lightning arrester is caused by the increase in the resistive leakage current. The zinc oxide arrester characteristic tester can infer whether it is damp or not by detecting the change of the viewing angle.