National Instruments PCI-1200 Manual De Usuario

© National Instruments Corporation

Figure 3-5 shows how to connect a floating signal source to a PCI-1200 
board configured for RSE mode. Configure the PCI-1200 analog input 
circuitry for RSE input to make these types of connections. Configuration 
instructions are in the 

 section of Chapter 2, 

Figure 3-5.  Single-Ended Input Connections for Floating Signal Sources

If you measure a grounded signal source with a single-ended configuration, 
configure the PCI-1200 in the NRSE input configuration. The signal is 
connected to the positive input of the PCI-1200 instrumentation amplifier 
and the signal local ground reference is connected to the negative input of 
the PCI-1200 instrumentation amplifier. Therefore, connect the ground 
point of the signal to the AISENSE pin. Any potential difference between 
the PCI-1200 ground and the signal ground appears as a common-mode 
signal at both the positive and negative inputs of the instrumentation 
amplifier and is therefore rejected by the amplifier. On the other hand, if 
the input circuitry of the PCI-1200 is referenced to ground, such as in the 

V

s

+

+

+

V

m

Measured

Voltage

Floating

Signal

Source

ACH0

AISENSE/AIGND

AGND

 I/O Connector

1

2

3

8

9

PCI-1200 in RSE Configuration

11

ACH1

ACH2

ACH7

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•

•

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