Measurement System Types and Signal Sources

The type of input signal source (grounded or floating) and the configuration of the measurement system (differential, single-ended, pseudodifferential) determine how you connect signals to measurement devices.

The following table provides an application-independent summary of analog input connections.

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)
Ground Referenced Single-Ended (RSE) Note: AI GND is shared as a reference for all RSE channels
Nonreferenced Single-Ended (NRSE) Note: AI SENSE is shared as a reference for all NRSE channels
Pseudodifferential
R ext is the external bias resistor that you add.