Measurement Computing CIO-EXP-RTD16 - Manual (Page 10)

3.6 DAISY-CHAINING CIO-EXP-RTD16 BOARDS
Connect one CIO-EXP-RTD16 to another using a C37FF-# ribbon cable. Connect from P2 on the
‘upstream’ board to P1 on the ‘downstream’ board. Make sure each of the boards in the chain have a
unique channel selected (CH SEL jumper is set to a different number on each board).
3.7 CONNECTING A VOLTAGE SIGNAL
Make your initial test of the CIO-EXP-RTD16 with a simple voltage signal of between 0 and 5V. If you
have a variable signal source, all the better.
+I
E
X
C
+S
E
N
S
E
−
IE
X
C
−
SE
N
SE
CH0
Voltage
Source
Add Jumper
Single-Ended Voltage Input
Signal-High
Signal-Low
(Gnd.)
Each input circuit has four screw terminals
associated with it. These terminals are shown in
Figure 3-6 to the right.
To connect a voltage signal to the input circuit you
need only use three screw terminals, these are:
+SENSE Connect the + voltage to this
-SENSE Place a wire between this and -IEXC
-IEXC Connect the Ground to this
Figure 3-6. Connection Terminal Block for
Voltage Test (Channel 0 Shown)
There is not room on the board for the full name next to each terminal so the eight screw terminals
associated with each input circuit are labeled on the CIO-EXP-RTD16 as follows:
+IEXC High side of RTD excitation current
+SENSE High side of input signal from voltage or RTD current
-IEXC Low side of excitation current or chassis ground for volts
-SENSE Low side of input signal from voltage or RTD
The use of the terminals is dependent on the type of sensor you have connected to the input circuit, and
the nomenclature on the terminals has been chosen to make the most sense for RTD sensors.
3.8 VERIFYING THE INSTALLATION
To verify the installation, test or calibrate the CIO-EXP-RTD16, use the InstaCal program installed on
your computer. This software came with your A/D board if you bought the board from the same
manufacturer as the CIO-EXP-RTD16. If your A/D board is not from the same manufacturer but is
compatible, please call technical support and request a copy of InstaCal.
Use InstaCal's TEST option to verify that a signal present at one of the CIO-EXP-RTD's inputs can be
read. You will not need to set any jumpers other than those previously mentioned, and should not set any
switches or install any passive components until you have verified the installation.
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