Does the Wait (ms) Function Needed After Switching Range?

Issue Details

I am using PXI-4081 to measure voltage. After changing the range in the niDMM Configure Measurement Digits.vi in LabVIEW and immediately acquire the measured value after that, sometimes NaN is being displayed. However, if I inserted a Wait (ms) function and set it 100 ms after changing the range, the NaN no longer appears. Is the Wait (ms) function needed after changing the range?

Solution

The Wait (ms) function is not necessarily required after changing the range of voltage measurement. Generally, the NI-DMM driver will make sure that all internal settling time had elapsed before the hardware makes the measurement. 

In some cases, the NaN is being displayed because of a possibility of delay occurring in the system probably due to the nature of the front-end configuration, which is the process of changing the indicator on the LabVIEW front panel, or due to the device under test (DUT). If delay occurred in the system, the addition of the Wait (ms) function might be necessary to ensure the hardware has verified all settings that have been changed before acquiring the measurement.