problem with 7831R's DGND

[smartkuku]

I use PXI-7831R to control a microwave component, and I found the 7831R's DGND is connected to the Chassis's ground. It make the component's shell and the 7831R's DGND connected, the DGND signal through the GPIB tranport to the component's shell. In this case, the component will not work properly and even more it will be broken. I wonder the DGND is directly connected to the PXI chassis's ground? or how to correct it.

[Ken_S]

Hello,

Yes, the DGND line is connected to Chassis Ground. If this is causing damage to your external device then you may consider synchronizing the ground references of the PXI chassis and the external device to eliminate any ground loops which may be occurring. This can be accomplished in many cases by connecting the external ground terminal (usually a small screw on the back of the PXI chassis) to the external device�s ground reference. For more information on grounding, I would suggest consulting the user manual for your PXI chassis.

If this is not feasible for you, or does not answer your question, please provide me with more information on which PXI chassis you are using and more information on your external device.

Hope this helps!

Ken S.
Applica
tions Engineering
National Instruments