Measurement Computing CIO-DAS16Jr/16 - Manual (Page 12)

The following sections depicts recommended input wiring schemes for each of the seven possible input
configuration/grounding combinations.
NOTE: For simplicity, the input multiplexers are not shown in the following diagrams.
2.3.1 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 2-5 below shows a basic connection diagram for a common ground / single-ended input system.
Figure 2-5 . Common Ground / Single-Ended Input
2.3.2 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 half the channels of a single-ended configuration. Figure 2-6 below shows the basic
connections in this configuration.
Figure 2-6. Common Ground / Differential Inputs
8
+
-
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 u rc e
w ith
C
o m m
o n G
n d
O p tio nal w ire
since sig na l sou rce
and A /D bo ard sh are
com m o n g round
S ig n a l s o urc e an d A /D b o a rd
s h a rin g c om m o n gro u n d c o n n e c te d
to s in g 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 Low
S ig
n a l
S
o urce
w ith
C o m
m o n
G n d
O ptio nal w ire
since signa l source
and A /D bo ard sha re
com m on g round
R equ ired connection
of L L G N D to C H Low
S ign a l s o u rc e an d A /D bo a rd
s ha ring c o m m o n g ro u nd c on n e c te d
to d iffe re n tia l in pu t.