Understand the working principle of medium voltage switchgear and how it safely controls, interrupts, and isolates current.
During normal operation, the medium voltage switchgear is in a closed state, with internal conductors forming a complete loop, and current flows smoothly from the input end to the output end. In terms of design, this stable operating state typically relies on the precise design of the internal circuit breaker and the conductive system, ensuring stable contact pressure and reducing resistance and heat generation.
When it needs to be disconnected or a fault occurs, the protection mechanism triggers immediately, causing the switch contacts to separate quickly and cut off the circuit. This action must be fast enough to reduce damage to the equipment.
An arc will be generated at the moment of disconnection, which is a normal phenomenon. The equipment uses special structures to stretch the arc and guide it into an arc chute, then cools and extinguishes it with insulating materials or media, ensuring the circuit is completely disconnected.
The final step is isolation. After the contacts separate, a physical gap visible to the naked eye is formed, ensuring that current absolutely cannot pass through and that it will not accidentally reconnect.
FAQs
1. In simple terms, how does MV switchgear operate in normal conditions?
It stays closed, so current flows in a stable loop from input to output. Wondon designed this structure for smooth and reliable power delivery.
2. What actually happens when a fault occurs?
The protection system reacts immediately, opens the circuit, and stops the current. Wondon focuses on fast response to protect equipment and reduce downtime.
3. Why is there sometimes an arc when switching off?
It’s a normal effect when the current is interrupted. Wondon designs arc control systems to safely manage and extinguish it.
4. How is the arc safely controlled and removed?
It is stretched, guided into an arc chamber, and cooled until it disappears. Wondon ensures this process is stable and fully controlled.
5. What does “isolation” actually mean in real operation?
It means a physical gap is created so current cannot pass through. Wondon ensures this separation is clear and completely safe for maintenance work.
