Optical MOSFET-based relays such as PhotoMOS have highly linear input and output characteristics that out-perform alternatives such as Triacs or opto-couplers. PhotoMOS relays can control small analog signals without distortion, unlike Triacs and bipolar transistors whose offset voltages distort and clip signals. Solid-state relays may have a higher initial cost than electromechanical relays; however the total cost over the relay’s life-cycle tips the scales back in favor of solid-state technology. Most of the operating cost advantages come from reductions in power consumption and a longer life-cycle (resulting in fewer relay replacements). The savings can be even more compelling when being used for the purpose of motor protection.