Archived:How to Test UMI 7772/7774 for Damage?

Updated Aug 14, 2018

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Reported In


  • Universal Motion Interface

Issue Details

I am not seeing expected behavior and want to check for damage to my Universal Motion Interface (UMI-7772 or UMI-7774). How can I verify that my limit, fault, interlock and inhibit IO is functioning?


Following these steps you should see two LEDs illuminate plus one per axis. Specifically, the V LED should illuminate green, the Interlock LED should illuminate red and each axis should have the Disabled LEDs illuminate red:
  1. Disconnect all inputs and outputs to the UMI.
  2. Verify that the power supply meets the specifications of the UMI.
  3. Verify that the power supply is not connected to any other device.
  4. Switch all of the dip switches to the Active High position.
  5. Connect the power supply to the UMI V and C terminal only.
To test the remaining Axis LEDs, switch the Fault and Limit LED dip switches:
  1. By switching the Fault dip switch to Active Low you should see the Fault LED illuminate red.
  2. By switching the Limit LED dip switch to Active Low you should see the FWD, Home and REV LEDs illuminate yellow.
  3. To test the Viso LED follow steps 2,3 and 5 above without disconnecting V and C. Either use a different power supply for Viso and Ciso or use the same power supply if it meets the specs of both terminals. To use the same power supply, use two wires to bridge the Viso terminal to the V terminal and Ciso terminal to the C terminal. When this is done the Viso LED should illuminate green.

Additional Information

The Inhibit All LED will not illuminate with a simple power test. To test the Inhibit All LED, as well as the Limit LEDs, connect the Viso and Ciso power as instructed. Using a wire, connect pin 8 of an Axis Control connector with pin 2 of the Global Stop connector. You should see Inhibit All illuminate red. Then connect pin 8 of the Control connector to pin 10, 11 and 12 of the Feedback connector and see the FWD, Home and REV LEDs toggle respectively.

The Interlock LED, as well as the Axis Disabled LEDs, should continue to illuminate until the Motion I/O connector is connected to an NI-Motion controller that is powered on as instructed in the manual. The Axis Disabled LEDs may remain illuminated once this cable is connected but the Interlock LED should turn off. For more information on these LEDs refer to the user manual and Why is the Interlock LED on my UMI-7774/7772 is always on?

If your LEDs illuminate or turn off as explained here, damage is not expected. However, if damage is suspected to the UMI board please contact National Instruments at


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