National Instruments 6008 User Manual And Specifications page 14

NI USB-6008/6009 User Guide and Specifications
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.
20
15
10
5
0
–5
–10
–15
–20
Figure 8. Example of a Differential 20 V Measurement
Connecting a signal greater than ±10 V on either pin results in a clipped
output.
20
15
10
5
0
–5
–10
–15
–20
Figure 9. Exceeding
±
10 V on AI Returns Clipped Output
14
AI 1
AI 5
Result
AI 1
AI 5
Result
ni.com