Grounding And Shielding Considerations - National Instruments NI USB-9219 User Manual

Wiring TEDS Channels

Grounding and Shielding Considerations

For best signal quality, National Instruments recommends using shielded cables and
Note
twisted-pair wiring whenever possible.
NI USB-9219 User Guide and Specifications
The NI USB-9219 supports only Class II TEDS sensors. Connect the two
TEDS lines to TEDS Data (T+) and TEDS COM (T–) and ensure that
neither T+ nor T– is tied in common to any of the signal inputs (terminals
3 through 6) on the NI USB-9219. Visit
code for information about TEDS sensors.
rdteds
You can connect ground-referenced or floating signal sources to the
NI USB-9219. If you make a floating connection between the signal source
and the NI USB-9219, make sure the voltages on the positive and negative
connections are within the channel-to-earth working voltage range to
ensure proper operation of the NI USB-9219. Refer to the
section for more information about operating voltages and overvoltage
protection.
Figures 8 and 9 illustrate connecting grounded and floating signal sources
to the NI USB-9219 in Voltage mode.
Signal Source
+
V
SIG
–
Figure 8. Connecting a Grounded Signal Source to the NI USB-9219
Signal Source
+
V
SIG
–
V Ground
SIG
Reference
Figure 9. Connecting a Floating Signal Source to the NI USB-9219
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Twisted-Pair
Shielding
Wiring
Twisted-Pair
Shielding
Wiring
12
and enter the info
Specifications
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NI USB-9219
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