National Instruments NI 9208E User manual

OPERATING INSTRUCTIONS AND SPECIFICATIONS
NI 9208E
16-Channel, ±20 mA, 24-Bit Analog Input Module

NI 9208E Operating Instructions and Specifications 2 ni.com
This document describes how to use the National Instruments 9208E
and includes dimensions, pin assignments, and specifications for the
NI 9208E. Visit ni.com/info and enter rdsoftwareversion to
determine which software you need for the modules you are using.
For information about installing, configuring, and programming the
system, refer to the system documentation. Visit ni.com/info and
enter cseriesdoc for information about C Series documentation.
Caution National Instruments makes no electromagnetic
compatibility (EMC) or CE marking compliance claims
for the NI 9208E. The end-product supplier is responsible
for conformity to any and all compliance requirements.
Caution The NI 9208E must be installed inside a suitable
enclosure prior to use. Hazardous voltages may be present.

© National Instruments Corp. 3 NI 9208E Operating Instructions and Specifications
NI 9208E Dimensions
The following figure shows the dimensions of the NI 9208E.
Figure 1. NI 9208E Dimensions in Millimeters (Inches)
73.4 (2.89)
0.0 (0.00)
26.7 (1.05)
58.4 (2.30)
66.0 (2.60)
0.0 (0.00)

NI 9208E Operating Instructions and Specifications 4 ni.com
Connecting the NI 9208E
The NI 9208E has a 37-pin DSUB connector that provides
connections for 16 analog input channels.
Figure 2. NI 9208E Pin Assignments
Vsup
Vsup
Vsup
Vsup
Vsup
Vsup
Vsup
Vsup
COM
COM
Vsup
Vsup
Vsup
Vsup
Vsup
Vsup
Vsup
Vsup
AI0
AI1
AI2
AI3
AI4
AI5
AI6
AI7
COM
COM
AI8
AI9
AI10
AI11
AI12
AI13
AI14
AI15
Vsup
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37

© National Instruments Corp. 5 NI 9208E Operating Instructions and Specifications
Each channel has an AI pin to which you can connect a current
signal. The NI 9208E also has 17 Vsup pins, one for connecting an
external power supply, and one for each channel. There are also
four common pins, COM, that are internally connected to the
isolated ground reference of the module.
The input signals are scanned, amplified, conditioned, and then
sampled by a single 24-bit ADC. The module provides overvoltage
protection for each channel. Only one channel can be in an
overvoltage condition at a time. Refer to the Specifications section
for information about overvoltage protection. Refer to Figure 3 for
an illustration of the input circuitry on the NI 9208E.

NI 9208E Operating Instructions and Specifications 6 ni.com
Figure 3. Input Circuitry on the NI 9208E
NI 9208E
RR
Amp Isolated
ADC
MUX
V
sup
V
sup
AI0
COM
COM
AI15

© National Instruments Corp. 7 NI 9208E Operating Instructions and Specifications
You can connect an external power supply to the NI 9208E. This
power supply provides the current for the devices you connect to
the module. Connect the positive lead of the power supply to a
Vsup pin and the negative lead of the power supply to COM. Install
a 2 A maximum, fast-acting fuse between the external power
supply and the Vsup pin. Refer to the Specifications section for
information about the Vsup pins.
Note The Vsup pins are internally connected to each
other. You can connect only one external voltage supply
to the device.
Caution Do not remove or insert modules if the external
power supply connected to the Vsup and COM pins is
powered on.

NI 9208E Operating Instructions and Specifications 8 ni.com
You can connect single-ended current signals to the NI 9208E,
including loop-powered and three-wire current transducers. To
connect a loop-powered transducer, connect the current signal to
the AI pin of the channel and the supply terminal to a Vsup pin. For
a three-wire transducer, also connect the common of the device to
COM. Refer to Figures 4 and 5 for illustrations of how to connect
loop-powered and three-wire current transducers to the NI 9208E.
Figure 4. Connecting a Loop-Powered Current Transducer to the NI 9208E
NI 9208E
+
–
COM
AI0
External
Power
Supply
Loop-Powered
Current
Transducer
Vsup
COM
Vsup
2 A
Max

© National Instruments Corp. 9 NI 9208E Operating Instructions and Specifications
Figure 5. Connecting a Three-Wire Current Transducer to the NI 9208E
NI 9208E
V
sup
COM
+
–
COM
V
sup
AI0
External
Power
Supply
Three-Wire
Current
Transducer
2 A
Max
OUT
+
–

NI 9208E Operating Instructions and Specifications 10 ni.com
Sleep Mode
This module supports a low-power sleep mode. Support for sleep
mode at the system level depends on the chassis that the module is
plugged into. Refer to the chassis manual for information about
support for sleep mode. If the chassis supports sleep mode, refer to
the software help for information about enabling sleep mode. Visit
ni.com/info and enter cseriesdoc for information about
C Series documentation.
Typically, when a system is in sleep mode, you cannot
communicate with the modules. In sleep mode, the system
consumes minimal power and may dissipate less heat than it does
in normal mode. Refer to the Specifications section for more
information about power consumption and thermal dissipation.