Life and maintenance of vacuum circuit breakers
The life and maintenance of vacuum circuit breakers need to comprehensively consider mechanical, electrical and environmental factors, as follows:
I. Life classification
A Vacuum life
The vacuum degree of the vacuum interrupter is used as an indicator, and the vacuum pressure is judged by testing whether it is lower than the allowable value. 1. The decrease in vacuum degree will cause the arc to reignite or break, and the interrupter needs to be replaced in time.
B Mechanical life
It is mainly determined by the mechanical parts of the operating mechanism (such as springs and electromagnetic mechanisms), which can usually reach more than 10,000 times. The bellows is a key component and is easily damaged by factors such as chemical corrosion, high temperature, excessive travel or friction.
C Electrical life
It is limited to contact wear or the number of interruptions, and is generally judged by the contact thickness or the number of interrupted currents. For example, the life of the spring operating mechanism is about 20,000 times at currents below 31.5kA, and it is shortened to 10,000 times above 40kA.
2. Maintenance cycle and maintenance
A Regular inspection
Daily maintenance: Check the operating mechanism (such as connecting rod stroke, opening and closing speed, bounce value) once a year, clean the conductive part and measure the contact resistance (≤80μΩ).
Operation number threshold: Temporary maintenance is required after the operation number reaches 1/5 of the mechanical life (such as 2000 times) or the short-circuit fault current reaches 20 times.
B Environment and abnormal handling
Shorten the cycle when the operating environment is harsh (such as humidity, corrosion); if poor insulation, discharge, component damage or abnormal sound is found, it should be stopped for maintenance immediately.
C Overhaul and replacement
When the mechanical life ends (such as bellows rupture) or the electrical life is exhausted, it needs to be replaced as a whole; the vacuum interrupter cannot be repaired on site, only replaced.
3. Precautions
Avoid reignition: The contact bounce time of new circuit breakers such as ZN12 is short (≤1ms), reducing load operation and manual opening and closing, and reducing vacuum loss.
Lubrication and tightening: Regularly lubricate the moving parts of the operating mechanism, check and tighten the fixing bolts to prevent increased wear.
Through scientific monitoring and maintenance, the life of the vacuum circuit breaker can be effectively extended and the safety of the power system can be guaranteed.
VTZ-12GD-MT vacuum circuit breaker combination electrical appliance produced by Shaanxi West Power Tongzhong Electrical Co., Ltd. is a special vacuum circuit breaker for underground mining with rated voltage of 12kV and AC 50/60Hz. It adopts permanent magnet mechanism and has mechanical manual closing and opening functions. It is suitable for various places with explosion-proof requirements for power facilities. The trolley unit is used in conjunction with PJG9-10 switch cabinet.
VTZ-12GD-MT vacuum circuit breaker combination electrical appliance has many advantages :
1.Safe and reliable: It adopts a combination of permanent magnet mechanism + spring mechanism, and the permanent magnet mechanism is used for normal operation; when the permanent magnet mechanism fails, the manual closing and opening operations are safe and reliable. The circuit breaker and the cabinet can achieve reliable mechanical interlocking to ensure the safety of the operator.
2. High conductivity: Reasonable conductive circuit design meets the temperature rise level of 1.1 times the rated current;
3. Highly integrated and intelligent configuration:
a. Wireless temperature intelligent monitoring solution can be added for self-power design, which is safe and maintenance-free;
b. The combined electrical appliance is equipped with an electrically operated isolating switch and grounding switch, which does not require external equipment and supports one-button sequential control
operation;
c.Manual cart, instead of fixed installation, is easy to maintain.
Should you have any requirements in these fields, please feel free to contact us as per following information:
Email: xdtz04@westpowerelectric.com
Website: https://www.xdtzelectrical.com/
Tel:+86 917 3661109
Mobilephone(whatsapp ): +86 18091765882
