How to Connect Wires to a cRIO or cDAQ Module with a Spring Terminal Connector

Updated Nov 18, 2022

Environment

Hardware

  • C Series Voltage Input Module
  • C Series Temperature Input Module
  • C Series Universal Analog Input Module
  • C Series Strain/Bridge Input Module
  • C Series Voltage Output Module
  • C Series Digital Module
  • cRIO Spring Terminal
  • 36-Position Front Mount Spring Terminal Connector
  • C Series Voltage and Current Input Module

I have a new CompactRIO or CompactDAQ module with a spring terminal connector. What is the correct way to connect to the spring terminal connector?

The spring terminal connectors have four columns and come in two types: one that interfaces with a small screwdriver or tool, and one that interfaces with orange tabs. In order to connect to the terminals, you will need individual wires. Wire end ferrules are not recommended. The spring terminal connectors are compatible with 28 - 18 AWG wire (0.5 - 1.0 mm).
Note: This information can also be located in your specific modules Getting Started Guide. To find the Getting Started Guide, search for your specific module on the NI Product Manual Search Page and locate the Connection Guidelines section within the PDF.


Screwdriver Interface

The outside columns are circular and accept stripped wire, and the two inner columns are square and are used to control the spring mechanism.
Complete the following steps to attach a wire to this type of spring terminal connector:
  1. Strip the wire about half an inch (more than 10mm).
  2. Insert a thin, flat screwdriver into the square hole adjacent to the circular hole you wish to use.
  3. Use the tip of the screwdriver to push the small metal piece towards the circular hole, and slide the stripped wire into the circular hole.
    1. Do not force the metal piece down. This action can bend the metal down and make it unusable. Make sure that the tool slides in between the wall of the socket and the small metal piece.
  4. Release the screwdriver from the square hole and the wire will be locked in place. 
Please refer to the image below to see how the piece should move.
 


Orange Tab Interface

The two inner columns are circular and accept stripped wire, and the two outer columns contain orange buttons that can be depressed to open the adjacent wire terminal. Do not remove the orange buttons.
Complete the following steps to attach a wire to this type of spring terminal connector:
  1. Strip the wire about half an inch (more than 10mm).
  2. Press down on the orange button, and insert the stripped end of a wire in the corresponding circular hole.
  3. Release the button to clamp the wire in place.