Maintenance and instructions for transformer accessories -lightning arrester

During daily operation, check the pollution condition of the porcelain bushing surface of the arrester, because when the porcelain bushing surface is seriously polluted, the voltage distribution will be very uneven. In the lightning arrester with shunt shunt resistor, when the voltage distribution of one element increases, the current through its shunt resistor will increase significantly, which may burn the shunt resistor and cause fault. In addition, it may also affect the arc-extinguishing performance of the valve type arrester. Therefore, when the surface of the arrester porcelain bushing is seriously polluted, it must be cleaned in time.

The hidden defects of the lightning arrester are most easily found by checking whether the lead and grounding down lead of the lightning arrester have burn marks and broken strands and whether the discharge recorder has burned through this aspect of inspection; Check whether the upper lead of the lightning arrester is well sealed. Poor sealing of the lightning arrester will lead to water ingress and damp, which may lead to accidents. Therefore, check whether the cement joint at the connection between the porcelain sleeve and the flange is tight, and install a waterproof cover at the upper lead of the 10 kV valve type lightning arrester to prevent rainwater infiltration; Check whether the electrical distance between the lightning arrester and the protected electrical equipment meets the requirements. The lightning arrester should be as close as possible to the protected electrical equipment. The lightning arrester should check the action of the recorder after the thunderstorm; Check the leakage current. When the power frequency discharge voltage is greater than or less than the standard value, repair and test shall be carried out; The discharge recorder shall be overhauled if it operates too many times; Cracks are found at the joint of porcelain bushing and cement; When the flange plate and rubber pad fall off, they should be repaired.

The insulation resistance of lightning arrester shall be checked regularly. The 2500 V insulation megger shall be used during the measurement. The measured value shall be compared with the previous result. If there is no obvious change, it can continue to be put into operation. When the insulation resistance drops significantly, it is generally caused by damp due to poor sealing or spark gap short circuit. When it is lower than the acceptable value, the characteristic test shall be conducted; When the insulation resistance increases significantly, it is generally caused by poor contact or fracture of the internal parallel resistance, spring relaxation and separation of internal components.

In order to find the hidden defects in the valve arrester in time, a preventive test should be carried out before the thunderstorm season every year.

一.safe operation

1. It is forbidden to touch the surface directly

When the lightning arrester is working normally, the surface temperature may rise, and touching the surface directly may cause skin burns. Therefore, when using a lightning arrester, do not touch the surface directly, but use tools to operate it.

2. It is prohibited to operate without supervision

During the use of lightning arresters, the monitoring status of the equipment should be maintained to ensure the safety of operation. It is prohibited to operate the lightning arrester without supervision.

3. Check the appearance before operation

Before operation, the appearance of the lightning arrester should be checked for damage and contamination. If so, it needs to be repaired or cleaned in time.

4. It is forbidden to replace the lightning arrester at will

The selection of lightning protectors needs to be selected according to the voltage level and requirements of the equipment. Different equipment uses different models of lightning protectors. Therefore, when using a lightning arrester, you must use a lightning arrester of corresponding specifications and cannot replace it at will.

5. It is prohibited to operate when there is current

Operating the lightning arrester when there is current may easily lead to electric shock accidents. Therefore, before operating the lightning arrester, be sure to cut off the power supply or ensure that the equipment is in a no-current state.

6. It is prohibited to open the case of the lightning arrester while using it.

The internal structure of the lightning arrester is relatively complex, so users should not open the casing at will. If you do not have professional knowledge and skills, do not repair and adjust the lightning arrester without permission.

7. Impact and impact on the lightning arrester are prohibited

The environment in which the lightning arrester is located is complex and changeable. If the lightning arrester is impacted and hit, it may be damaged, thus affecting its normal use. Therefore, during use, attention should be paid to protecting the lightning arrester to avoid impacts and other unnecessary external interference.

二.Maintenance procedures

1. Regular cleaning

Lightning arresters are easily attracted to dust and dirt. If not cleaned in time, the working effect of the lightning arrester will be affected. Therefore, the lightning arrester needs to be cleaned regularly, and a special lightning arrester cleaning fluid can be selected for cleaning.

2. Regular inspection

During the operation of the lightning arrester, there may be faults such as burnout and damage. Therefore, when using the lightning arrester, it needs to be inspected regularly. If problems are found, they need to be repaired and replaced in time.

3. Avoid exposure to the sun and high temperature environment

Lightning arresters should be stored in a dry, cool environment and avoid direct exposure to the sun and high temperature environments. Long-term exposure to the sun and high temperature environment will cause the packaging material on the lightning protector to crack and age, thus affecting the service life of the lightning protector.

4. Other matters needing attention

The service life of lightning arresters is generally 3-5 years. They need to be replaced after the warranty period: Used lightning arresters must be properly disposed of and cannot be discarded at will: lightning arresters should be kept dry and clean to block foreign matter, etc.

Summarize:

Lightning arrester is a common electrical equipment, but due to the large voltage and current it generates, if you do not pay attention to safe operation during use, it can easily cause electric shock accidents. Therefore, when using lightning arresters, it is necessary to strictly abide by safe operating procedures and perform maintenance and repairs in accordance with regulations to ensure their normal use and extend their service life.