Taking Referenced Single-Ended Measurements - National Instruments USB-6008 User Manual

The differential input mode can measure ±20 V signals in the ±20 V range. However, the
maximum voltage on any one pin is ±10 V with respect to GND. For example, if AI 1 is +10 V
and AI 5 is -10 V, then the measurement returned from the device is +20 V.
Figure 9. Example of a Differential 20 V Measurement
20
15
10
5
0
–5
–10
–15
–20
Connecting a signal greater than ±10 V on either pin results in a clipped output.
Figure 10. Exceeding ±10 V on AI Returns Clipped Output
20
15
10
5
0
–5
–10
–15
–20

Taking Referenced Single-Ended Measurements

To connect referenced single-ended (RSE) voltage signals to the NI USB-6008/6009, connect
the positive voltage signal to an AI terminal, and the ground signal to a GND terminal, as
shown in the following figure.
16 | ni.com | NI USB-6008/6009 User Guide
AI 1
AI 5
Result
AI 1
AI 5
Result