The type of input signal source (grounded or floating) and the configuration of the measurement system (differential, single-ended, psuedodifferential) determine how you connect signals to measurement devices.
The following table provides an application-independent summary of analog input connections. The resistors in the figures are not the same as those for measuring current, resistance, and strain.
Input | Signal Source Type | |
Floating Signal Source (Not Connected to Building Ground) | Grounded Signal Source | |
Examples: Ungrounded thermocouples, signal conditioning with isolated outputs, battery devices | Example: Instruments with nonisolated outputs | |
Differential (DIFF) | ![]() |
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Ground Referenced Single-Ended (RSE) Note: AI GND is shared as a reference for all RSE channels | ![]() |
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Nonreferenced Single-Ended (NRSE)Note: AI SENSE is shared as a reference for all NRSE channels | ![]() |
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Psuedodifferential | ![]() |
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Rext is the external bias resistor that you add. |