Measurement Computing CIO-DAS160x/1x - Manual (Page 18)

5.2.1 Common Ground / Single-Ended Inputs
Single-ended is the recommended configuration for common ground connections. However, if some of
your inputs are common ground and some are not, we recommend you use the differential mode. There is
no performance penalty (other than loss of channels) for using a differential input to measure a common
ground signal source. However the reverse is not true. Figure 5-4 below shows a recommended
connection diagram for a common ground / single-ended input system
Figure 5-4. Common Ground / Single-Ended Inputs
5.2.2 Common Ground / Differential Inputs
The use of differential inputs to monitor a signal source with a common ground is a acceptable
configuration though it requires more wiring and offers fewer channels than selecting a single-ended
configuration. Figure 5-5 below shows the recommended connections in this configuration.
Figure 5-5. Common Ground / Differential Inputs
14
+
-
In p u t
A m p
To A /D
A /D B o a rd
I/O
C o n n e c to r
LL G N D
C H IN
S ig n
a l
S
o urce
w ith
C o
m m o n
G n d
O p tio nal w ire
since signa l sou rce
and A /D bo ard sh are
com m on g round
S ign a l so u rce an d A /D bo a rd
s ha ring c om m o n gro u n d con n e cte d
to s ing le -en d ed inp u t.
+
-
In p u t
A m p
To A /D
A /D B o a rd I/O
C o n n e c to r
LL G N D
C H H igh
C H L ow
S ig n
al
S
o urc e
w ith
C
o m m
o n G n
d
O p tio nal w ire
since signa l sou rce
and A /D bo ard sha re
com m o n g round
R equ ired connection
of L L G N D to C H Low
S ign a l so urce an d A /D bo a rd
sha ring co m m o n gro u nd con n e cte d
to d iffe re ntia l in pu t.