BusWorks XTA-120V-6 optocoupler modules have six individually isolated 120 Vac/dc digital (discrete) inputs to sense on/off levels, and provide 5-32 Vdc logic outputs to a fieldbus input module or controller. XTA-MRNO-6 interposing relay module receives 4-32 Vdc logic-level signals from an output module or controller to switch six mechanical relay outputs. These high-voltage relay interface modules monitor or control inductive and other high-power loads with control system input/output modules that only support low-level dc signals.