National Instruments NI-9421 C Series Digital Module

The NI 9421 (Part Numbers: 779002-01, 779136-01, 779136-02, 783734-01, 779136-02) belongs to the C Series and is a Digital Module, which works with mechanical logic levels to connect specifically to a big cluster of modern switches, transducers, and gadgets. In addition, the NI-9421 has 8 digital input channels and Sinking Inputs. Each channel is compatible with 12V, 24 V digital I/O logic levels. To show the condition of the channel, there is a LED. This module offers separation between the input channels and earth ground.

There are four variations of the NI-9421 module. The NI 9421 with screw terminals, part number 779002-01, has 250 Vrms Ch-Earth Ground Isolation. The NI 9421 with D-Sub connectors, part numbers 779136-01 and 779136-02, has 60 VDC Ch-Earth Ground Isolation. Lastly, part number 783734-01 has Spring Terminal front connectors and 250 Vrms Ch-Earth Ground Isolation. In addition, part number 779136-02 is the only variation that is conformal coated. The NI 9421 has a power consumption value of up to 240 mW when active, and 7 mW maximum when in sleep mode.

The DI provide a route to COM to the energy or voltage. The NI 9421 possess sinking inputs, which sends a message that the external gadget is driving current or applies voltage to the DI terminal or stick. The current signals associated with DI are limited by the NI 9421. If an application utilizing the NI 9421 with screw terminals is liable to high vibration, National Instruments suggests that the user utilize ferrules to end wires to the separable screw-terminal connector or utilize a backshell connector for added protection. This module additionally has a low-power rest mode. Support for rest mode at the framework level relies upon the chassis that the module is connected to.

The NI device weighs 5.1 oz. It has recommended operating and storage temperature ranges of -40 °C to 70 °C and -40 °C to 85 °C, non-condensing operating and storage humidity ranges of 10% RH to 90% RH and 5% RH to 95% RH, random and sinusoidal operating vibrations of 5 grms and 5 g respectively–all at a frequency range of 10 to 500 Hz.