The ADAM-4051 is a 16-ch. Digital Input Module, built with 2500 VDC optical isolation, suitable for critical applications. Different from other modules, the ADAM-4051 accepts 10~50V input voltage to fit various digital signals, such as 12 VDC, 24 VDC, 48 VDC. Moreover, users can read the current status from the LED indications on the front panel.