National Instruments USB-9237 User manual

USER GUIDE AND SPECIFICATIONS
NI USB-9237
4-Channel, 24-Bit Half/Full-Bridge Analog Input Device
This user guide describes how to use the National Instruments USB-9237
and lists the device specifications. The NI USB-9237 provides a USB
interface for four channels of 24-bit half/full-bridge analog input.
Introduction
The NI USB-9237 consists of two components: an NI 9237 module and an
NI USB-9162 carrier, as shown in Figure 1.
Figure 1. NI USB-9237 Components
NI 9237
NI USB-9162
NI USB-9237
Hi-SPeed USB Carrier
NI USB-9162
Hi-Speed USB Carrier
NI USB-9162

NI USB-9237 User Guide and Specifications 2 ni.com
Dimensions
Figure 2 shows the NI USB-9237 device dimensions.
Figure 2. NI USB-9237 Device in Millimeters (Inches)
Safety Guidelines
Operate the NI USB-9237 only as described in these operating instructions.
Note Although the NI 9237 module may have more stringent certification standards than
the NI USB-9237, when used with the NI USB-9162 carrier, the combined system may be
limited. Refer to the Specifications section for more details.
Hot Surface This icon denotes that the component may be hot. Touching this component
may result in bodily injury.
Caution Do not disconnect I/O-side wires or connectors unless power has been switched
off or the area is known to be nonhazardous.
Caution Do not remove modules unless power has been switched off or the area is known
to be nonhazardous.
Caution The NI USB-9237 is not certified for use in hazardous locations.
123.67 mm
(4.869 in.)
121.28 mm
(4.775 in.)
120.68 mm
(4.751 in.)
118.29 mm
(4.567 in.)
Hi-Speed USB Carrier
NI USB-9162
88.11 mm
(3.469 in.) 25.08 mm
(0.988 in.)

©National Instruments Corporation 3 NI USB-9237 User Guide and Specifications
Related Documentation
Each application software package and driver includes information about
writing applications for taking measurements and controlling measurement
devices. The following references to documents assume you have
NI-DAQmx 8.7 or later, and where applicable, version 7.1 or later of the
NI application software.
NI-DAQmx for Windows
The DAQ Getting Started Guide describes how to install your NI-DAQmx
for Windows software, your NI-DAQmx-supported DAQ device, and how
to confirm that your device is operating properly. Select Start»All
Programs»National Instruments»NI-DAQ»DAQ Getting Started
Guide.
The NI-DAQ Readme lists which devices are supported by this version of
NI-DAQ. Select Start»All Programs»National Instruments»NI-DAQ»
NI-DAQ Readme.
The NI-DAQmx Help contains general information about measurement
concepts, key NI-DAQmx concepts, and common applications that are
applicable to all programming environments. Select Start»All
Programs»National Instruments»NI-DAQ»NI-DAQmx Help.
LabVIEW
If you are a new user, use the Getting Started with LabVIEW manual to
familiarize yourself with the LabVIEW graphical programming
environment and the basic LabVIEW features you use to build data
acquisition and instrument control applications. Open the Getting Started
with LabVIEW manual by selecting Start»All Programs»National
Instruments»LabVIEW»LabVIEW Manuals or by navigating to the
labview\manuals directory and opening LV_Getting_Started.pdf.
Use the LabVIEW Help, available by selecting Help»Search the
LabVIEW Help in LabVIEW, to access information about LabVIEW
programming concepts, step-by-step instructions for using LabVIEW, and
reference information about LabVIEW VIs, functions, palettes, menus, and
tools. Refer to the following locations on the Contents tab of the LabVIEW
Help for information about NI-DAQmx:
•Getting Started»Getting Started with DAQ—Includes overview
information and a tutorial to learn how to take an NI-DAQmx
measurement in LabVIEW using the DAQ Assistant.
•VI and Function Reference»Measurement I/O VIs and
Functions—Describes the LabVIEW NI-DAQmx VIs and properties.

NI USB-9237 User Guide and Specifications 4 ni.com
•Taking Measurements—Contains the conceptual and how-to
information you need to acquire and analyze measurement data in
LabVIEW, including common measurements, measurement
fundamentals, NI-DAQmx key concepts, and device considerations.
LabWindows/CVI
The Data Acquisition book of the LabWindows/CVI Help contains
measurement concepts for NI-DAQmx. This book also contains Taking an
NI-DAQmx Measurement in LabWindows/CVI, which includes
step-by-step instructions about creating a measurement task using the DAQ
Assistant. In LabWindows™/CVI™, select Help»Contents, then select
Using LabWindows/CVI»Data Acquisition.
The NI-DAQmx Library book of the LabWindows/CVI Help contains API
overviews and function reference for NI-DAQmx. Select Library
Reference»NI-DAQmx Library in the LabWindows/CVI Help.
Measurement Studio
If you program your NI-DAQmx-supported device in Measurement Studio
using Visual C++, Visual C#, or Visual Basic .NET, you can interactively
create channels and tasks by launching the DAQ Assistant from MAX or
from within Visual Studio .NET. You can generate the configuration code
based on your task or channel in Measurement Studio. Refer to the DAQ
Assistant Help for additional information about generating code. You also
can create channels and tasks, and write your own applications in your
ADE using the NI-DAQmx API.
For help with NI-DAQmx methods and properties, refer to the NI-DAQmx
.NET Class Library or the NI-DAQmx Visual C++ Class Library included
in the NI Measurement Studio Help. For general help with programming in
Measurement Studio, refer to the NI Measurement Studio Help, which is
fully integrated with the Microsoft Visual Studio .NET help. To view
this help file in Visual Studio. NET, select Measurement Studio»
NI Measurement Studio Help.
To create an application in Visual C++, Visual C#, or Visual Basic .NET,
follow these general steps:
1. In Visual Studio .NET, select File»New»Project to launch the New
Project dialog box.
2. Find the Measurement Studio folder for the language you want to
create a program in.
3. Choose a project type. You add DAQ tasks as a part of this step.

©National Instruments Corporation 5 NI USB-9237 User Guide and Specifications
ANSI C without NI Application Software
The NI-DAQmx Help contains API overviews and general information
about measurement concepts. Select Start»All Programs»National
Instruments»NI-DAQ»NI-DAQmx Help.
The NI-DAQmx C Reference Help describes the NI-DAQmx Library
functions, which you can use with National Instruments data acquisition
devices to develop instrumentation, acquisition, and control applications.
Select Start»All Programs»NationalInstruments»NI-DAQ»
NI-DAQmx C Reference Help.
.NET Languages without NI Application Software
With the Microsoft .NET Framework version 1.1 or later, you can use
NI-DAQmx to create applications using Visual C# and Visual Basic .NET
without Measurement Studio. You need Microsoft Visual Studio
.NET 2003 or Microsoft Visual Studio 2005 for the API documentation
to be installed.
The installed documentation contains the NI-DAQmx API overview,
measurement tasks and concepts, and function reference. This help is fully
integrated into the Visual Studio .NET documentation. To view the
NI-DAQmx .NET documentation, go to Start»Programs»National
Instruments»NI-DAQ»NI-DAQmx .NET Reference Help. Expand
NI Measurement Studio Help»NI Measurement Studio .NET Class
Library»Reference to view the function reference. Expand NI
Measurement Studio Help»NI Measurement Studio .NET Class
Library»Using the Measurement Studio .NET Class Libraries to view
conceptual topics for using NI-DAQmx with Visual C# and Visual
Basic .NET.
To get to the same help topics from within Visual Studio, go to
Help»Contents. Select Measurement Studio from the Filtered By
drop-down list and follow the previous instructions.
Device Documentation and Specifications
NI-DAQmx includes the Device Document Browser, which contains
online documentation for supported DAQ, SCXI, and switch devices, such
as help files describing device pinouts, features, and operation, and PDF
files of the printed device documents. You can find, view, and/or print the
documents for each device using the Device Document Browser at any
time by inserting the CD. After installing the Device Document Browser,
device documents are accessible from Start»All Programs»National
Instruments»NI-DAQ»Browse Device Documentation.
Note You can download these documents at ni.com/manuals.

NI USB-9237 User Guide and Specifications 6 ni.com
Training Courses
If you need more help getting started developing an application with
NI products, NI offers training courses. To enroll in a course or obtain a
detailed course outline, refer to ni.com/training.
Technical Support on the Web
For additional support, refer to ni.com/support or zone.ni.com.
Installing the Software
Software support for the NI USB-9237 for Windows Vista/XP/2000 is
provided by NI-DAQmx. The DAQ Getting Started Guide, which you can
download at ni.com/manuals, offers NI-DAQmx users step-by-step
instructions for installing software and hardware, configuring channels and
tasks, and getting started developing an application.
Installing Other Software
If you are using other software, refer to the installation instructions that
accompany your software.
Example Programs
The NI-DAQmx CD contains example programs that you can use to get
started programming with the NI USB-9237. Refer to the NI-DAQmx for
USB Devices Getting Started Guide that shipped with your device, and is
also accessible from Start»All Programs»National Instruments»
NI-DAQ,for more information.
Installing the NI USB-9237 Device
Before installing the device, you must install the software you plan to use
with the device. Refer to the Installing the Software section of this guide
and the documentation included with the software for more information.
Installing the NI 9237 in the USB-9162 Carrier
The NI 9237 module and USB-9162 carrier are packaged separately. Refer
to Figure 3, while completing the following assembly steps:
1. Make sure that no signals are connected to the NI 9237 module and the
USB cable is not connected to the device.
2. Remove the protective cover from the 15-pin D-SUB connector.

©National Instruments Corporation 7 NI USB-9237 User Guide and Specifications
3. Align the I/O module with the carrier, as shown in Figure 3.
Figure 3. Module Installation
4. Squeeze the latches and insert the NI 9237 module into the USB-9162
carrier.
5. Press firmly on the connector side of the NI 9237 module until the
latches lock the module into place, as shown in Figure 4.
Figure 4. Locking Module into Place

NI USB-9237 User Guide and Specifications 8 ni.com
Mounting the NI USB-9237 to a Panel
Threaded inserts are located in the NI USB-9237 for mounting it to a panel.
Refer to Figure 5 for dimensions.
Figure 5. Module Dimensions in Millimeters (Inches)
Connecting the NI USB-9237 to a Computer
Plug one end of the USB cable into the NI USB-9237 and the other end into
an available USB port on the computer. Refer to the NI-DAQmx for USB
Devices Getting Started Guide that shipped with your device, and is also
accessible from Start»All Programs»National Instruments»NI-DAQ,
for more information.
LED Indicator
The NI USB-9237 device has a green LED next to the USB connector. The
LED indicator indicates device status, as listed in Table 1. When the device
is connected to a USB port, the LED blinks steadily to indicate that the
device is initialized and is receiving power from the connection.
If the LED is not blinking, it may mean that the device is not initialized or
the computer is in standby mode. In order for the device to be recognized,
the device must be connected to a computer that has NI-DAQmx installed
on it. If your device is not blinking, make sure your computer has the latest
version of NI-DAQmx installed on it, and the computer is not in standby
mode.
72.2 mm
(2.84 in.)
85.7 mm
(3.37 in.)
76.1 mm
(3.00 in.)
Threaded Insert
M3 x 0.5
8.5 mm (0.34 in.) Max Depth

©National Instruments Corporation 9 NI USB-9237 User Guide and Specifications
Wiring the NI USB-9237 Device
The NI USB-9237 has four RJ-50 receptacles that provide connections for
four half or full bridges. Table 2 lists the signal names of the terminals for
each connector, and shows the correlation between the pin numbers of
the RJ-50 10-position/10-conductor (10p10c) modular plug and the
NI USB-9237 receptacle. The NI USB-9237 also has a four-position
connector you can use to connect an external excitation voltage source to
the module. Table 2 lists the connections between an external excitation
voltage source and the NI USB-9237.
Note For a list of accessories available for use with the NI USB-9237, refer to
ni.com/info, and enter info code rd9237.
Table 1. LED State/Device Status
LED State Device Status
Not lit Device not connected or in suspend.
On, not blinking Device connected, but no module installed.
Single-blink Operating normally.
Double-blink Connected to USB Full-Speed port. Device
performance might be affected. Refer to the
Specifications section for more information.
Quadruple-blink Device error. Refer to ni.com/support.

NI USB-9237 User Guide and Specifications 10 ni.com
Caution National Instruments does not recommend using an RJ-45 with the NI USB-9237
because it can physically damage pins 1 and 10 on the device, and thus permanently disable
shunt calibration no matter what connector you use.
Table 2. Terminal Assignments
RJ-50 (10p10c)
Modular Plug
and Receptacle
Pin Numbers RJ-50 Pin RJ-45 Pin
Signal
Name
Signal
Description
1 — SC Shunt calibration
2 1 AI+ Positive input
signal
3 2 AI– Negative input
signal
4 3 RS+ Positive remote
sense signal
5 4 RS– Negative remote
sense signal
6 5 EX+ Positive
excitation signal*
7 6 EX– Negative
excitation signal*
8 7 T+ TEDS data
9 8 T– TEDS return*
10 — SC Shunt calibration
* These signals are shared by all four RJ-50 connectors on the NI USB-9237.