Indoor high-voltage switch vacuum circuit breakerDetailed product description：

The ZN21-12 indoor high-voltage vacuum circuit breaker is a product with international advanced level manufactured by introducing advanced foreign technology. This product not only has high mechanical reliability, long electrical life, and strong breaking ability, but also has a small size and light weight, making it a high-performance non maintenance circuit breaker that can replace imported ones.

The product structure is simple and compact, with complete operating functions. Its operating mechanism is a spring energy storage type, which can be operated by AC or DC or manually. It also has anti bounce protection and can be installed with voltage loss and overcurrent release devices. Compared with previous switches, it is smaller in size and lighter in weight. The operating mechanism and electrical components are integrated into a single structure, which not only makes the structure of the switch more compact, but also makes the switch work more reliably. This circuit breaker can be installed on a fixed frame to become a fixed switch, or installed in the frame to become a handcart switch. Regardless of the installation method, it does not affect the mechanical and electrical performance of the circuit breaker.  

The ZN21-12 indoor high-voltage switch vacuum circuit breaker is particularly suitable for use with a mid mounted switchgear to replace imported circuit breakers due to its small size. It can also be installed in a double-layer mid mounted switchgear, making it smaller in size and occupying less space. The primary part of the circuit breaker is installed on a three-phase integrated insulation frame, and the vacuum arc extinguishing chambers of each phase are fixed in U-shaped slots. It not only has high mechanical strength and can overcome the electric force generated by short-circuit current, but also improves the composite insulation strength between phases. The insulation frame made of new high-strength, high flame retardant, unsaturated polyester SMC can effectively prevent the expansion of an accident and avoid the impact of an accident on the operating mechanism and secondary parts. Due to the adoption of reliability design, the mechanical and electrical reliability of the product has been improved, and it does not require maintenance for 20 years under normal usage conditions. In special circumstances, when the short-circuit current of the circuit breaker reaches the specified number of times, it only needs to replace the vacuum arc extinguishing chamber to be reused, and its performance is restored to its original state. There are multiple product specifications and a wide range of varieties, from small currents with large quantities and wide coverage to high currents with special requirements, fully meeting the various needs of users. This product is a 12KV three-phase AC 50Hz high-voltage switchgear, suitable for control or protection of power transmission and distribution systems such as power plants and substations, especially for important loads and frequent operations in chemical, metallurgical, mining and other places.  

The ZN21-12 indoor high-voltage vacuum circuit breaker complies with the requirements of GB 1984 "AC High Voltage Circuit Breakers", JB 3855 "3.6-40.5KV Indoor High Voltage Vacuum Circuit Breakers", DL/T 402 "Technical Conditions for Ordering AC High Voltage Circuit Breakers", and relevant requirements of IEC 56.