National Instruments NI-9481 C Series Relay Output Module

The NI 9481 National Instruments has four channels, single-pole single throw (SPST) relays, and is designed for any NI CompactDAQ or CompactRIO Chassis. Each of the four channels on this module offers access to an electromechanical relay for switching signals to 30 VDC (2 A), 60 VDC (1 A), and 250 VAC (2 A) maximum. This SPST Electromechanical Relay Module allows the user to link straight to a variety of industrial instruments, including DC instruments, actuators, and motors.

Every relay channel has two interchangeable terminals, CHa and CHb. Every channel also has an LED that shows the status of the channel. When a channel LED is lit up, it means the channel is on. When the LED is dark, then it indicates the channel is not on. The LEDs are deactivated when the chassis is in sleep mode. When linking a load to the NI-9481, the user can join the positive lead of the load to the CHa or CHb terminal, and the ground of the load to a single load of the power supply. Then, the user can link the last CHa or CHb terminal to the other lead of the power supply.

Users should note that 2-wire ferrules should be utilized to generate a secure link when joining more than a single wire to one terminal on the NI-9481 C Series Relay Output Module. If an application is prone to extreme vibration, then National Instruments suggests that the user should utilize ferrules to terminate wires to the detachable screw-terminal connector. The other option is to utilize the NI-9932 backshell kit to safeguard the links.