The IC200MDL240 brings 16 AC discrete inputs into a single VersaMax module slot — 120 VAC nominal, organized in two isolated groups of 8 channels each with a dedicated common per group. The AC input design means this module connects directly to the 120 VAC control circuits that dominate North American industrial panels: motor starter auxiliary contacts, pushbutton stations, float switches, pressure switches, and limit switches — all devices whose standard control voltage is 120 VAC, derived from a control transformer in the panel. The input impedance of 8.6 kΩ at 60 Hz limits the per-point current to approximately 14 mA at nominal voltage, keeping the total module dissipation low enough that no external cooling is required. The module is backplane-powered (110 mA at 5 VDC) — no separate field power supply needed for the inputs themselves, because the AC voltage on the field terminals is the power source for the input detection circuit.

Group isolation: why two groups of 8 matters

The two groups are galvanically isolated from each other (1500 VAC for 1 minute) — meaning a ground fault on group 1 (wired to a limit switch on a machine frame with a compromised ground bond) does not affect the inputs on group 2 (wired to a pushbutton station on an operator console with a different ground reference). In practice, this allows a single IC200MDL240 to monitor devices on two different machines, two different panels, or two different buildings — each with its own 120 VAC control power source — without ground loops, without common-mode noise coupling, and without the risk of a single ground fault taking down all 16 inputs simultaneously.