A distributed control system is provided having a plurality of control modules operative to control one or more output devices. A control module includes a first enclosure that houses a plurality of control terminals and a second enclosure that houses a controller for controlling an output device. A maximum voltage of the first enclosure is less than a threshold voltage level, and a maximum voltage of the second enclosure is greater than the threshold voltage level. A safety circuit of the control system includes a plurality of circuit segments connected in a series configuration to the control modules.