Analysis Of The Reason Why The Length Of The Crank Handle For Setting The High-voltage Disconnect Switch Is 0.9m.

The standard length for a high voltage electrical isolator type of jack is typically 0.9m. This length is derived from considerations of the coordination between the equipment installation height and the operator's posture. During the design phase of isolator high voltage, this length will be determined based on the site environment, high-voltage room layout, operating space, and operating safety angle.

The 0.9m length is matched with the height of the high voltage isolator panel, allowing operators to naturally perform the opening and closing operations while standing. The equipment is usually installed in a substation or feeder room, with the panel positioned within the operator's natural line of sight and reach. If the crank handle is too short, hand operation will be too low; if it's too long, it will affect space arrangement or interfere with nearby components.