A switch disconnector consists of two or more metal contact blades or poles that are either connected or separated by an operating handle. When the handle is turned to the ON position, the contacts close and current flows; when switched OFF, the contacts open, creating an air gap that guarantees isolation. Many GRL isolator switches use spring-assisted mechanisms: a double-spring energy storage unit stores kinetic energy so that when you operate the handle, the contacts snap open or closed rapidly. This spring release makes switching fast and reduces arcing, even if the handle is moved slowly.
Auxiliary features further enhance the safety and functionality of isolator switches. For instance, GRL’s designs often include a rotary multi-break contact structure that increases the isolation distance for better safety. They also provide auxiliary contacts or position indicators that give remote signals of the switch status.
Many models have a visible ON/OFF window so maintenance personnel can see at a glance whether the switch is open.
In the OFF (“O”) position, the handle can usually be locked or sealed, preventing accidental or unauthorized closing.
In summary, the operating principle is simple: mechanically separate the circuit conductors under no-load conditions, with robust mechanisms and indicators to ensure a safe, visible isolation of power.
