I'm using two 6221's to control an XY displacement table. Table motion is controlled by applying voltages to its X and Y input channels. Position feedback is output on the table's X and Y feedback lines. The problem is that input voltages on one channel show up in the feedback signals of the other channel. For example input voltages on the X channel appear superimposed at low but significant levels on the Y feedback signal, and vice versa.
I'm using one 6221 to drive the table and another 6221 to receive position feedback. No channel crosstalk is observed when feedback voltages are measured with a multi-meter. It only occurs when both X and Y feedback lines are connected to the 6221. Ground switch settings (grounded/floating source) located below each input BNC connector on the 6221 have no impact.
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