FUJI ELECTRIC INDUSTRY CO., LTD.

If the equipment status related to circuits is shown with lamps, on the electric power system panel, the broken wire in any lamp disables this display making it impossible to determine the equipment status. Since the semaphore relay uses no lamp, the open / closed status of the equipment is always displayed accurately. The semaphore relay allows for visually checking whether the circuit is connected or not. The disconnecting switch and circuit-breaker, which shows their statuses with the round and square shapes, are simple and contributes to the improvement of the panel design.