The Omron K3MA-JA2-24VAC/DC is a process meter — a panel-mounted digital indicator that displays a scaled reading from a 4-20 mA, 0-10 V, or other analog process signal. It takes a live loop or voltage input from a transmitter (pressure, flow, temperature) and shows the engineering unit value on its display, with scaling and offset configurable via front-panel buttons. The 24 VAC/DC supply means it runs off the same control transformer or DC bus common in most industrial panels, no separate power supply module needed.
Panel-mount form factor, cutout per the K3MA series standard. Wiring is screw-terminal, accepting the loop or voltage input plus the 24 VAC/DC supply. The display is readable from a few meters away, which matters when the meter is mounted on a cabinet door and the operator is at the machine. No special isolation required for the signal input, but keep the loop wiring away from VFD output cables to avoid coupled noise.