Chapter 4
Connecting and Using Accessories and Transducers
4-10
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Failure to verify that the common-mode voltage is within specified limits can damage the
SCXI system and is potentially dangerous. National Instruments is not liable for damages
or injuries resulting from improper configuration. If you have a large common-mode
voltage (>30 V
rms
and 42.4 V
peak
or 60 VDC), ground the terminal block to safety earth
ground as shown in Figure 4-4.
Connect the strain gauge to the SCXI-1321 terminal block as shown in
Figure 4-4. You can also use the SCXI-1320 for this arrangement.
Figure 4-4.
Connecting the Half-Bridge Strain Gauge to Channel 1 of the
SCXI-1321 Terminal Block
CH 0
EX 0
CH 1
EX 1
CH 2
EX 2
CH 3
EX 3
+
-
+
-
+
-
+
-
+
-
+
-
+
-
+
-
CHAS
GND
Safety Earth
Ground for High Common-Mode
Voltage (>30 V
rms
and 42.4 V
peak
or 60 VDC)
Ex +
Ex -