Rse configuration) -11 – National Instruments DAQCard-1200 User Manual
Page 33
Chapter 3
Signal Connections
© National Instruments Corporation
3-11
Single-Ended Connection Considerations
Single-ended connections are those in which all DAQCard-1200 analog
input signals are referenced to one common ground. The input signals are
tied to the positive input of the instrumentation amplifier, and their
common ground point is tied to the negative input of the instrumentation
amplifier.
When the DAQCard-1200 is configured for single-ended input (NRSE or
RSE), eight analog input channels are available. You can use single-ended
input connections when the following criteria are met by all input signals:
•
Input signals are high level (greater than 1 V).
•
Leads connecting the signals to the DAQCard-1200 are less than 15 ft.
•
All input signals share a common reference signal (at the source).
If any of the preceding criteria is not met, you should use DIFF input
configuration.
You can software configure the DAQCard-1200 for two different types of
single-ended connections, RSE configuration and NRSE configuration.
Use the RSE configuration for floating signal sources; in this case, the
DAQCard-1200 provides the reference ground point for the external signal.
Use the NRSE configuration for ground-referenced signal sources; in this
case, the external signal supplies its own reference ground point and the
DAQCard-1200 should not supply one.
Single-Ended Connections for Floating Signal Sources
(RSE Configuration)
Figure 3-5 shows how to connect a floating signal source to a
DAQCard-1200 configured for single-ended input. You must configure the
DAQCard-1200 analog input circuitry for RSE input to make these types
of connections. For configuration instructions, refer to the