Introduction to BSB
BSB Electric, headquartered in Lishui, Zhejiang, China, has become a leader in the high-voltage DC contactor market since the launch of its first product series in 2015. With a manufacturing facility spanning over 46,000 square meters, BSB integrates semi-automated and fully automated production lines, including injection molding, stamping, mold manufacturing, CNC processing, and dust-free assembly.
Sealing Forms of BSB High Voltage DC Contactor Relays
BSB high voltage DC contactors utilize advanced sealing technologies to ensure optimal performance under extreme conditions. These sealing forms protect the internal components from environmental damage and help maintain consistent operation in both industrial and commercial applications.
They are categorized by sealing type into: epoxy resin-sealed contactors, ceramic brazed-sealed contactors, and non-hermetic sealed contactors.
Contact Forms of BSB High Voltage DC Contactor Relays
The contact forms include normally open (NO), normally closed (NC), and changeover (CO).
For sealed high-voltage DC contactors, the main contacts are usually available in one set of normally open or normally closed forms, while the auxiliary contacts typically include one set of normally open, one set of normally closed, and one set of changeover contacts (BSBC7 epoxy resin sealed series).
Function of auxiliary contacts (low voltage): They are primarily used to monitor the state (on or off) of the main contacts (high voltage) and provide feedback to the control system.
Internal structure of BSB High Voltage DC Contactor Relays
Process Flow in the Manufacturing of BSB High Voltage DC Contactors
Basic Parameters of BSB High Voltage DC Contactor Relays
The basic parameters of the contactor consist of five main electrical parameters and insulation withstand voltage.
Characteristics and Requirements of BSB High Voltage DC Contactor Relays
- Electrical durability
- Switching life (making the circuit)
- Breaking life (breaking the circuit)
- Switching and breaking life (making and breaking the circuit)
- Current-carrying temperature rise
- Temperature rise definition: The temperature increase of each component in electrical equipment above the ambient temperature (in units of K)
- Contact temperature rise: According to the GB/T 14048.1 standard, bare copper contacts ≤ 60K, copper-plated silver contacts ≤ 65K
- Coil temperature rise: Typically based on the rated operating temperature of the enamelled wire. For epoxy products, the enamelled wire is F-grade with a continuous operating temperature ≤ 155°C; for ceramic products, the enamelled wire is H-grade with a continuous operating temperature ≤ 180°C
- Measures to reduce temperature rise: Reduce heat generation (current passing through resistance leads to = I² * R * t, which is independent of voltage), improve heat dissipation
- Note: Materials in contact with heat-generating components should also be considered to ensure they meet the required temperature rise tolerance
- Short-circuit resistance
- Mechanical durability
- Mechanical life
- Impact and vibration
- Environmental reliability
- Temperature, humidity, salt spray, altitude pressure, electromagnetic interference, and other combined tests
Safety and Environmental Certifications for BSB High Voltage DC Contactor Relays
- RoHS and REACH requirements
- Flammability requirements for plastic materials
- Certification requirements for CQC, UL, TUV, CE, etc.
- Air gap and creepage distance (to be measured during certification)
Plastic Flammability Requirements of BSB High Voltage DC Contactor Relays
Plastic flammability: 5VA > 5VB > V0 > V1 > V2 > HB
For high-voltage DC contactors, the plastic flammability must meet the V-0 grade
Creepage distance and air gap for BSB High Voltage DC Contactor Relays
Creepage distance: The shortest path measured along the insulating surface between two conductive components or between a conductive component and the protective interface of the device
Electrical clearance: The shortest spatial distance measured between two conductive components or between a conductive component and the protective interface of the device
Selection Requirements of BSB High Voltage DC Contactor Relays
The design service life of the product should comprehensively consider the following factors:
- Meet the electrical life requirements during the service life.
- Meet the environmental factors that affect the life of the device.
- For sealed contactors, consider ensuring seal integrity throughout the service life.
- Meet the current-carrying temperature rise requirements during the service life.
- Ensure safety performance requirements are met during the service life.
Applications
