The KNC-PLC-K623 Discrete Input and Output Expansion Modules are offered in Transistor or Relay outputs and sinking or sourcing inputs. These units come with 4 inputs and 4 outputs or 8 inputs and 8 outputs. These units are ideal to expand beyond the onboard inputs and outputs of the KNC-PLC-K6 CPUs, which can handle up to 264 I/O points with a maximum of 14 expansion modules. The inputs are rated for 3.5 mA and can be configured for either sourcing or sinking. The transistor outputs are rated for 500 mA @ 24 VDC and come only in a sourcing configuration. The relay outputs are rated for 2 A @ 30 VDC or 250 VAC, and are great for switching on and off high load devices AC or DC devices, particularly AC or DC motors. The transistor output modules are opto-isolated for unit protection.