Test & Measurement
24 V, 8-Channel (Sinking Input), 100 µs C Series Digital Module - The NI‑9421 works with industrial logic levels and signals to connect directly to a wide array of industrial switches, transducers, and devices. Each channel is compatible with 24 V logic levels and has an LED indicating the state of that channel. The NI‑9421 offers isolation between the input channels and earth ground.