The OMRON GRT1-PD8 is a Power Feed Unit for the GRT1 Series Smart Slice I/O System. It is used in conjunction with a GRT1 Series communication unit (such as the GRT1-CRT for DeviceNet). Its primary purpose is to supply external 24 VDC power to the I/O circuits (field power) of subsequent I/O slices (e.g., digital outputs, analog outputs) in the same station, while also passing the internal communications power to the rest of the slices.