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Connecting Input Signals
You can connect floating and grounded input signals to the FieldDAQ device. Make sure that
devices you connect to the FieldDAQ device are compatible, as listed in the
FD-11634
Specifications
.
The FD-11634 provides an IEPE excitation current for each channel to measure the IEPE
sensors. Typical IEPE sensors have a case that is electrically isolated from the IEPE
electronics. As a result, connecting the sensor to the FD-11634 results in a floating connection
even though the case of the sensor is grounded.
•
Floating Signal Sources
Figure 12. Connecting Floating Signal Sources to the FieldDAQ Device
Signal
Source
AI-
+
–
AI+
2
4
•
Grounded Signal Sources
—To ensure proper operation, make sure the voltage on the
AI+ and AI- connections adhere to the channel-to-earth ground safety voltage
specifications listed in the
FD-11634 Specifications
.
Figure 13. Connecting Grounded Signal Sources to the FieldDAQ Device
Signal
Source
AI-
+
–
AI+
2
4
Common
Mode
Voltage
Connecting TEDS Sensors
You can connect TEDS (Transducer Electronic Data Sheets) sensors to the FieldDAQ device
through the AI+ and AI- pins on each connector.
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FD-11634 User Guide