Measurement Computing CIO-DAS08-PGH - Manual (Page 9)

3: ANALOG CONNECTIONS
3.1 ANALOG INPUTS
Prior to jumping into actual connection schemes, you should have at least a basic understanding of Single-Ended/Differential
inputs and system grounding/isolation. If you are already comfortable with these concepts you may wish to skip to the next section
(on wiring configurations).
3.1.1 Single-Ended and Differential Inputs
The CIO-DAS08-PGx provides either 8 differential or 16 single-ended input channels. The concepts of single-ended and
differential inputs are discussed in the following section.
Single-Ended Inputs
A single-ended input measures the voltage between the input signal and ground. In this case, in single-ended mode the
CIO-DAS08-PGx measures the voltage between the input channel and LLGND. The single-ended input configuration requires
only one physical connection (wire) per channel and allows the board to monitor more channels than the differential configuration
using the same connector and onboard multiplexer (Figure 3-1). However, since the CIO-DAS08-PGx is measuring the input
voltage relative to its own low level ground, single-ended inputs are more susceptible to both EMI (electro magnetic interference)
and any ground noise at the signal source. The following diagrams show the single-ended input configuration. Note: For
simplicity, the input multiplexer is not shown.
Figure 3-1. Single-Ended Input Configuration (Simplified)
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