Tulip Contact, Fixed Contact, Contact Arm—Important Vacuum Circuit Breaker Contacts Components

What is a vacuum circuit breaker contacts assembly?

Now let us start to learn the important primary conductive components of the vacuum circuit breaker: tulip contacts, fixed contacts, contact arms.

Tulip contact is the main contact used to break or turn on the circuit, while fixed contact is used to support and fix the plummer contact, and also can play a certain role in breaking the electricity. The contact arm is the part that connects the plum contact and the static contact, and plays the role of transmitting current. The synergy of these three components enables the circuit breaker to effectively protect circuits and equipment from faults and accidents caused by excessive current.

Tulip contact is a common contact form, its shape is similar to a plum blossom. It has the characteristics of large contact area, reliable contact, and wear resistance, and can effectively conduct current and maintain stable contact. Tulip contacts are used for primary conduction in high-voltage vacuum circuit breakers, central cabinets, handcarts, etc.

The GC series primary movable contacts are independently developed and developed on the basis of digesting and absorbing ABB product technology, replacing all domestically produced products of similar imported products. Widely used in handcart type circuit breakers such as ZN63 (VS1, VB1). Its performance complies with the requirements of GB3906-1991<3~35KV AC metal-enclosed switchgear.

Tulip contact structures: contact, support frame, spring, support frame is annular, a number of contacts are assembled on the support frame to form an annular body.

Structural features of tulip contacts

1. Non-magnetic stainless steel bracket is electrolytically polished;
2. Non-magnetic stainless steel ring-shaped tension spring binding;
3. The contact piece is fine-blanked from T2 copper plate, and the surface is plated with thick silver. It will not discolor for a long time after anti-tarnish treatment and has a beautiful appearance.

Fixed contacts are contacts whose position basically remains unchanged during operation. It is usually made of copper, which has good electrical conductivity and corrosion resistance. Fixed contacts do not require frequent movements, so they have a longer life. It is mainly used in high-voltage switch cabinets, but not in low-voltage switch cabinets.

The contact arm is the component that connects the tulip contact and the fixed contact and is used to transmit current. The contact arm is also a contact whose position basically remains unchanged during operation. It is used as an auxiliary part in KYN type armored metal-enclosed switchgear and JYN-type spaced metal-enclosed switchgear. It can also be used in other handcart-type switch equipment and has the characteristics of reliable contact, excellent electrical performance, and easy use. The contact arm is usually made of copper, which has good electrical conductivity and mechanical strength. The design of the contact arm should take into account factors such as current load, contact pressure and contact area to ensure a stable electrical connection.

Product parameters

Maintenance points for contacts

1. Regularly check the wear of the contacts and contact arms. If there is any wear, replace them in time to ensure good contact performance.
2. Clean the surfaces of the contacts and contact arms to remove dust and oxides to reduce contact resistance and avoid spark discharge.
3. Check the tightness of the contacts and contact arms to ensure that they are installed firmly and reliably.
4. Conduct regular insulation tests to ensure that the insulation performance of the switch cabinet or vacuum circuit breaker meets the requirements to prevent electrical accidents and failures.