Device driving method, and a device driving apparatus, a signal switching apparatus

摘要

A signal switching apparatus comprising multiple relays, multiple photocouplers, wherein an output from the photocouplers is connected to the coils of the multiple relays, and a control device that controls the photocouplers. The coils of the above-mentioned multiple relays are connected so that they are distributed between a positive electrical source and a negative electrical source so that the current flowing to the ground is small.