2-34
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Chapter 2
Analog Input and Temperature Sensor Measurements
Figure 2-33.
Measuring Current with Differential Analog Inputs
•
Single-ended analog inputs
—To build a one-resistor circuit that measures current at the
single-ended analog inputs of the SCB-68A, add the resistor to position B or D, depending
on the channel being used. Leave the 0
Ω
resistors in place for channel positions F and G,
respectively. Refer to Table 2-1 for component positions for all analog input channels.
Calculate the current according to the following equation,
where
R
B
or
D
is the resistance of the resistor in position B or D.
AI
i
AI
i
+
8
y
S
C
x
E
A
F
G
B
C
D
+
+
+
+ 5 V
AI GND
+ 5 V
AI GND
AI
i
AI
i
+
8
I
V
m
R
B
or
D
----------------
=
