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Chapter 2
Using the Module
Channel Types
The PXIe-4480 and PXIe-4481 support the measurement applications shown in Table 2-6.
For maximum flexibility, the module’s channel type is programmable on a per-channel basis.
Channel Configuration
The PXIe-4480/4481 supports two terminal configurations for analog voltage input: differential
and pseudodifferential. The term
pseudodifferential
refers to the 50 Ω
resistance between the
negative input terminal and chassis ground.
Note
Attach the PXIe-4480/4481 to the chassis with the screws on the top and
bottom of the front panel to provide a reliable ground connection.
If the signal source is floating, use the pseudodifferential input configuration. The
pseudodifferential configuration provides a ground reference connection for the floating source
by connecting a 50 Ω resistor from the negative input to ground. Without this, the floating source
can drift outside of the common-mode range of the module.
Table 2-6.
Supported Measurement Applications
Application
PXIe-4480
PXIe-4481
Direct voltage
Voltage-based sensors that are externally powered
IEPE sensors (powered with embedded IEPE current source)
including TEDS
Amplified/powered sensors (powered with embedded voltage
excitation source)
*
Charge sensors (measured with embedded charge-to-voltage
amplifier)
*
Embedded voltage excitation source is accessible only when using an accessory, such as the
SHB12X-6RJ50, that provides access to the excitation terminals.
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