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IEPE Excitation
The PXIe-4480 provides an integrated electronic piezoelectric (IEPE) excitation current for
each channel to measure IEPE or other current-excited sensors. To match a variety of sensor
requirements, the current source is configurable with three settings: 4 mA, 10 mA, and 20 mA.
For maximum flexibility, the module’s IEPE current selection is programmable on a per-channel
basis.
Note
Typical IEPE sensors have an enclosure that is electrically isolated from the
IEPE electronics. As a result, connecting the sensor to the PXIe-4480 results in a
floating connection even though the enclosure of the sensor is grounded.
Transducer Electronic Data Sheet
The PXIe-4480 supports Class 1 Transducer Electronic Data Sheet (TEDS) according to the
IEEE 1451.4 standard.
TEDS-capable sensors carry a built-in, self-identification EEPROM that stores a table of
parameters and sensor information. TEDS sensors have two modes of operation:
•
Analog mode
allows the sensors to operate as transducers measuring physical phenomena.
•
Digital mode
allows you to write and read information to and from the TEDS.
TEDS contains information about the sensor, such as calibration, sensitivity, and manufacturer
information. This information is accessible in Measurement & Automation Explorer (MAX),
VIs in LabVIEW, or by calling the equivalent function calls in a text-based ADE.
For more information on TEDS structure and contents, go to
Code
rdted6
.
Voltage Excitation
The PXIe-4480 provides a programmable voltage excitation source for each channel, designed
primarily to interface with powered/amplified sensors. This type of sensor accepts a
wide-ranging external power source, regulates it to a voltage suitable for its internal electronics,
and provides its signal on amplifier output terminals.
Note
The voltage excitation feature is available only when using an accessory, such
as the SHB12X-6RJ50, that provides access to the excitation terminals.
