Dongfa Intelligent supplies global high voltage vacuum circuit breaker manufacturers and switchgear builders with factory-direct Circuit Breaker Operating Coils. Operating coils (closing/opening coils) are core execution components for circuit breaker switching operations. They are short-time duty, with energization time typically only tens to hundreds of milliseconds.
Main products include DC220V 131.5Ω, 130Ω, 98Ω, 47Ω; DC110V 33Ω; DC48V 4Ω; AC220V 56Ω, covering plug-in, lead wire, double-ended shaft, and long stroke structures. Selection requires focusing on operating voltage, coil resistance, steady-state current, instantaneous power, push rod stroke, shaft type, reset method, and mounting holes.
Coil resistance and voltage are directly paired — choose the matching voltage level first, then verify current and thermal load.
Operating coils are short-time duty devices. Long-term energization is strictly prohibited — sustained power will cause coil overheating and burnout. Always verify that the auxiliary contact in the control circuit reliably opens after each closing or opening operation.
Dongfa Intelligent was founded in 2012 in Yueqing Economic Development Zone, Wenzhou, Zhejiang. Factory area over 2,000㎡, 17 employees, 4 technical engineers, 2 production lines, 1 set of testing equipment. Monthly capacity 600–700 units, annual capacity 7,000–8,000 units. Products exported to Southeast Asia and parts of Europe.
Operating coils are assembled on dedicated low voltage lines. Each unit undergoes resistance testing and dielectric withstand testing before shipment. Coil resistance is individually verified to ensure ±5% consistency. Simulated short-time energization testing verifies instantaneous action capability.
“We purchased Dongfa Intelligent's DC220V 131.5Ω closing/opening coils for VS1 vacuum circuit breakers. Resistance consistency was excellent, and switching time was stable. Their technical team helped us confirm compatibility with the operating mechanism.” — Procurement Manager, High Voltage Switchgear Manufacturer
