CT40 Spring operated mechanism (dual auxiliary switch)

The CT-40 spring operated mechanism is suitable for operating LW35-40.5 self charging SF6 circuit breakers and switch cabinets with equivalent power to circuit breakers. It can drive the circuit breaker body to perform opening and closing operations, achieving various operations. Using spring energy storage as the power source, coupled with dual auxiliary switches to achieve precise control and status feedback, it is widely used in 10kV-40.5kV medium voltage distribution systems, industrial substations, and distribution networks, providing stable and efficient power support for the opening and closing operations of switchgear and ensuring the safe operation of power systems.
1、 Core working principle: Collaborative control of spring energy storage and dual auxiliary switch
1. Spring energy storage mechanism
The CT40 mechanism uses cylindrical spiral springs as the core energy storage component, and the energy storage process is achieved through manual or electric methods:
Electric energy storage: The motor drives the reduction gear set, which drives the energy storage shaft to rotate and compresses the closing spring through the cam mechanism; When the spring is compressed to the rated stroke, the energy storage pawl and ratchet lock, and the stroke switch triggers the motor to stop, completing the energy storage (energy storage time ≤ 15s). At this time, the mechanism is in a state of waiting to be closed.
Manual energy storage: When the motor fails or there is no power supply, rotate the energy storage shaft manually by shaking the handle, repeat the compression spring and locking process described above, and ensure that the energy storage operation can still be completed in emergency situations.
2. Logic of opening and closing actions
Closing operation: When receiving the closing signal, the closing electromagnet will act, releasing the energy storage pawl, and the closing spring will quickly release energy, pushing the switch device's moving contact to close through the connecting rod transmission mechanism; After the closing is completed, the opening spring is synchronously stretched to store energy, preparing for the opening operation.
Opening operation: When receiving the opening signal, the opening electromagnet (or manual opening handle) will act, the opening lock will release, the opening spring will release energy, and the transmission mechanism will be driven to quickly pull the moving contact to disconnect, cutting off the circuit (opening time ≤ 25ms, ensuring quick disconnection of fault current).
3. The core function of dual auxiliary switches
Different from the single auxiliary switch model, the CT40's dual auxiliary switch design achieves "functional separation and redundancy guarantee", with specific functions including:
State feedback switch: Real time monitoring of the "energy storage status" (stored/not stored) and "closing status" (fully closed/fully opened) of the mechanism, transmitting status signals to the distribution automation system (such as SCADA) for remote monitoring of equipment operation status.
Control interlock switch: Implement logical interlocking of "energy storage closing" and "opening closing", for example: the closing circuit is only connected when the mechanism completes energy storage (triggered by the status feedback switch); When the opening is not in place, the closing operation is locked to prevent equipment damage caused by misoperation and improve operational safety.