Risk Of Overtravel During High-voltage Disconnection Switch Operation

The mechanism of High Voltage Disconnect Switch connects or disconnects via mechanical contacts, with an insulating air gap between the contacts providing a clear indication of disconnection. During the closing action, the moving and stationary contacts must accurately engage to the specified positions to maintain the contact resistance within the set range; otherwise, poor contact, mechanical wear, or even localized overheating may occur.

If the disconnecting switch's closing action exceeds the predetermined stroke, it will increase the possibility of mechanical stress and abnormal distribution of the insulation electric field, affecting the switch's lifespan and electrical safety. High-voltage disconnecting switches lack additional arc-extinguishing devices; their contacts can only connect when the current is close to zero. Otherwise, an electric arc will occur, leading to mechanical damage or system failure.