DAQ
SCB-68 68-Pin Shielded
Connector Block User Manual
SCB-68 Shielded Connector Block User Manual
December 2002 Edition
Part Number 320745B-01
ni.com
11500 North Mopac Expressway Austin, Texas 78759-3504 USA Tel: 512 683 0100
Australia 03 9879 5166, Austria 0662 45 79 90 0, Belgium 02 757 00 20, Brazil 55 11 3262 3599, Canada (Calgary) 403 274 9391, Canada (Montreal) 514 288 5722, Canada (Ottawa) 613 233 5949, Canada (Québec) 514 694 8521, Canada (Toronto) 905 785 0085, China 86 21 6555 7838,
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Slovenia 3 425 4200, South Africa 11 805 8197, Spain 91 640 0085, Sweden 08 587 895 00, Switzerland 056 200 51 51, Taiwan 02 2528 7227, United Kingdom 01635 523545
For further support information, refer to the Technical Support and Professional Services appendix. To comment on the documentation, send email to techpubs@ni.com.
© 1994–2002 National Instruments Corporation. All rights reserved.
The SCB-68 is warranted against defects in materials and workmanship for a period of one year from the date of shipment, as evidenced by receipts or other documentation. National Instruments will, at its option, repair or replace equipment that proves to be defective during the warranty period. This warranty includes parts and labor.
The media on which you receive National Instruments software are warranted not to fail to execute programming instructions, due to defects in materials and workmanship, for a period of 90 days from date of shipment, as evidenced by receipts or other documentation. National Instruments will, at its option, repair or replace software media that do not execute programming instructions if National Instruments receives notice of such defects during the warranty period. National Instruments does not warrant that the operation of the software shall be uninterrupted or error free.
A Return Material Authorization (RMA) number must be obtained from the factory and clearly marked on the outside of the package before any equipment will be accepted for warranty work. National Instruments will pay the shipping costs of returning to the owner parts which are covered by warranty.
National Instruments believes that the information in this document is accurate. The document has been carefully reviewed for technical accuracy. In the event that technical or typographical errors exist, National Instruments reserves the right to make changes to subsequent editions of this document without prior notice to holders of this edition. The reader should consult National Instruments if errors are suspected. In no event shall National Instruments be liable for any damages arising out of or related to this document or the information contained in it.
EXCEPT AS SPECIFIED HEREIN, NATIONAL INSTRUMENTS MAKES NO WARRANTIES, EXPRESS OR IMPLIED, AND SPECIFICALLY DISCLAIMS ANY WARRANTY OF MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE. CUSTOMER’S RIGHT TO RECOVER DAMAGES CAUSED BY FAULT OR NEGLIGENCE ON THE PART OF
NATIONAL INSTRUMENTS SHALL BE LIMITED TO THE AMOUNT THERETOFORE PAID BY THE CUSTOMER. NATIONAL INSTRUMENTS WILL NOT BE LIABLE FOR
DAMAGES RESULTING FROM LOSS OF DATA, PROFITS, USE OF PRODUCTS, OR INCIDENTAL OR CONSEQUENTIAL DAMAGES, EVEN IF ADVISED OF THE POSSIBILITY
THEREOF. This limitation of the liability of National Instruments will apply regardless of the form of action, whether in contract or tort, including negligence. Any action against National Instruments must be brought within one year after the cause of action accrues. National Instruments shall not be liable for any delay in performance due to causes beyond its reasonable control. The warranty provided herein does not cover damages, defects, malfunctions, or service failures caused by owner’s failure to follow the National Instruments installation, operation, or maintenance instructions; owner’s modification of the product; owner’s abuse, misuse, or negligent acts; and power failure or surges, fire, flood, accident, actions of third parties, or other events outside reasonable control.
Under the copyright laws, this publication may not be reproduced or transmitted in any form, electronic or mechanical, including photocopying, recording, storing in an information retrieval system, or translating, in whole or in part, without the prior written consent of National Instruments Corporation.
DAQCard™, National Instruments™, NI™, and ni.com™ are trademarks of National Instruments Corporation.
Product and company names mentioned herein are trademarks or trade names of their respective companies.
For patents covering National Instruments products, refer to the appropriate location: Help»Patents in your software, the patents.txt file on your CD, or ni.com/patents.
(1)NATIONAL INSTRUMENTS PRODUCTS ARE NOT DESIGNED WITH COMPONENTS AND TESTING FOR A LEVEL OF RELIABILITY SUITABLE FOR USE IN OR IN CONNECTION WITH SURGICAL IMPLANTS OR AS CRITICAL COMPONENTS IN ANY LIFE SUPPORT SYSTEMS WHOSE FAILURE TO PERFORM CAN REASONABLY BE EXPECTED TO CAUSE SIGNIFICANT INJURY TO A HUMAN.
(2)IN ANY APPLICATION, INCLUDING THE ABOVE, RELIABILITY OF OPERATION OF THE SOFTWARE PRODUCTS CAN BE IMPAIRED BY ADVERSE FACTORS, INCLUDING BUT NOT LIMITED TO FLUCTUATIONS IN ELECTRICAL POWER SUPPLY, COMPUTER HARDWARE MALFUNCTIONS, COMPUTER OPERATING SYSTEM SOFTWARE FITNESS, FITNESS OF COMPILERS AND DEVELOPMENT SOFTWARE USED TO DEVELOP AN APPLICATION, INSTALLATION ERRORS, SOFTWARE AND HARDWARE COMPATIBILITY PROBLEMS, MALFUNCTIONS OR FAILURES OF ELECTRONIC MONITORING OR CONTROL DEVICES, TRANSIENT FAILURES OF ELECTRONIC SYSTEMS (HARDWARE AND/OR SOFTWARE), UNANTICIPATED USES OR MISUSES, OR ERRORS ON THE PART OF THE USER OR APPLICATIONS DESIGNER (ADVERSE FACTORS SUCH AS THESE ARE HEREAFTER COLLECTIVELY TERMED “SYSTEM FAILURES”). ANY APPLICATION WHERE A SYSTEM FAILURE WOULD CREATE A RISK OF HARM TO PROPERTY OR PERSONS (INCLUDING THE RISK OF BODILY INJURY AND DEATH) SHOULD NOT BE RELIANT SOLELY UPON ONE FORM OF ELECTRONIC SYSTEM DUE TO THE RISK OF SYSTEM FAILURE. TO AVOID DAMAGE, INJURY, OR DEATH, THE USER OR APPLICATION DESIGNER MUST TAKE REASONABLY PRUDENT STEPS TO PROTECT AGAINST SYSTEM FAILURES, INCLUDING BUT NOT LIMITED TO BACK-UP OR SHUT DOWN MECHANISMS. BECAUSE EACH END-USER SYSTEM IS CUSTOMIZED AND DIFFERS FROM NATIONAL INSTRUMENTS' TESTING PLATFORMS AND BECAUSE A USER OR APPLICATION DESIGNER MAY USE NATIONAL INSTRUMENTS PRODUCTS IN COMBINATION WITH OTHER PRODUCTS IN A MANNER NOT EVALUATED OR CONTEMPLATED BY NATIONAL INSTRUMENTS, THE USER OR APPLICATION DESIGNER IS ULTIMATELY RESPONSIBLE FOR VERIFYING AND VALIDATING THE SUITABILITY OF NATIONAL INSTRUMENTS PRODUCTS WHENEVER NATIONAL INSTRUMENTS PRODUCTS ARE INCORPORATED IN A SYSTEM OR APPLICATION, INCLUDING, WITHOUT LIMITATION, THE APPROPRIATE DESIGN, PROCESS AND SAFETY LEVEL OF SUCH SYSTEM OR APPLICATION.
FFCC/Canada Radio Frequency Interference Compliance
Determining FCC Class
The Federal Communications Commission (FCC) has rules to protect wireless communications from interference. The FCC places digital electronics into two classes. These classes are known as Class A (for use in industrial-commercial locations only) or Class B (for use in residential or commercial locations). Depending on where it is operated, this product could be subject to restrictions in the FCC rules. (In Canada, the Department of Communications (DOC), of Industry Canada, regulates wireless interference in much the same way.)
Digital electronics emit weak signals during normal operation that can affect radio, television, or other wireless products. By examining the product you purchased, you can determine the FCC Class and therefore which of the two FCC/DOC Warnings apply in the following sections. (Some products may not be labeled at all for FCC; if so, the reader should then assume these are Class A devices.)
FCC Class A products only display a simple warning statement of one paragraph in length regarding interference and undesired operation. Most of our products are FCC Class A. The FCC rules have restrictions regarding the locations where FCC Class A products can be operated.
FCC Class B products display either a FCC ID code, starting with the letters EXN, or the FCC Class B compliance mark that appears as shown here on the right.
Consult the FCC Web site at http://www.fcc.gov for more information.
FCC/DOC Warnings
This equipment generates and uses radio frequency energy and, if not installed and used in strict accordance with the instructions in this manual and the CE Marking Declaration of Conformity*, may cause interference to radio and television reception. Classification requirements are the same for the Federal Communications Commission (FCC) and the Canadian Department of Communications (DOC).
Changes or modifications not expressly approved by National Instruments could void the user’s authority to operate the equipment under the FCC Rules.
Class A
Federal Communications Commission
This equipment has been tested and found to comply with the limits for a Class A digital device, pursuant to part 15 of the FCC Rules. These limits are designed to provide reasonable protection against harmful interference when the equipment is operated in a commercial environment. This equipment generates, uses, and can radiate radio frequency energy and, if not installed and used in accordance with the instruction manual, may cause harmful interference to radio communications. Operation of this equipment in a residential area is likely to cause harmful interference in which case the user will be required to correct
the interference at his own expense.
Canadian Department of Communications
This Class A digital apparatus meets all requirements of the Canadian Interference-Causing Equipment Regulations. Cet appareil numérique de la classe A respecte toutes les exigences du Règlement sur le matériel brouilleur du Canada.
Class B
Federal Communications Commission
This equipment has been tested and found to comply with the limits for a Class B digital device, pursuant to part 15 of the FCC Rules. These limits are designed to provide reasonable protection against harmful interference in a residential installation. This equipment generates, uses, and can radiate radio frequency energy and, if not installed and used in accordance with the instructions, may cause harmful interference to radio communications. However, there is no guarantee that interference will not occur in a particular installation. If this equipment does cause harmful interference to radio or television reception, which can be determined by turning the equipment off and on, the user is encouraged to try to correct the interference by one or more of the following measures:
•Reorient or relocate the receiving antenna.
•Increase the separation between the equipment and receiver.
•Connect the equipment into an outlet on a circuit different from that to which the receiver is connected.
•Consult the dealer or an experienced radio/TV technician for help.
Canadian Department of Communications
This Class B digital apparatus meets all requirements of the Canadian Interference-Causing Equipment Regulations. Cet appareil numérique de la classe B respecte toutes les exigences du Règlement sur le matériel brouilleur du Canada.
Compliance to EU Directives
Readers in the European Union (EU) must refer to the Manufacturer’s Declaration of Conformity (DoC) for information* pertaining to the CE Marking compliance scheme. The Manufacturer includes a DoC for most every hardware product except for those bought for OEMs, if also available from an original manufacturer that also markets in the EU, or where compliance is not required as for electrically benign apparatus or cables.
To obtain the DoC for this product, click Declaration of Conformity at ni.com/hardref.nsf/. This Web site lists the DoCs by product family. Select the appropriate product family, followed by your product, and a link to the DoC appears in Adobe Acrobat format. Click the Acrobat icon to download or read the DoC.
*The CE Marking Declaration of Conformity will contain important supplementary information and instructions for the user or installer.
About This Manual
Conventions ................................................................................................................... |
xi |
NI Documentation.......................................................................................................... |
xii |
Chapter 1
Introduction
What You Need to Get Started ...................................................................................... |
1-1 |
Quick Reference Label .................................................................................................. |
1-2 |
Installing Cables ............................................................................................................ |
1-5 |
Using 68-Pin Cables ........................................................................................ |
1-5 |
Using 100-Pin Cables ...................................................................................... |
1-6 |
Configuring the SCB-68 ................................................................................................ |
1-11 |
Safety Information ......................................................................................................... |
1-11 |
Chapter 2
Parts Locator and Wiring Guide
Switch Configuration ..................................................................................................... |
2-3 |
Chapter 3
Connecting Signals
Connecting Analog Input Signals .................................................................................. |
3-1 |
Input Modes..................................................................................................... |
3-1 |
Nonreferenced or Floating Signal Sources...................................................... |
3-3 |
Differential Inputs ............................................................................. |
3-3 |
Single-Ended Inputs .......................................................................... |
3-3 |
Ground-Referenced Signal Sources ................................................................ |
3-4 |
Differential Inputs ............................................................................. |
3-4 |
Single-Ended Inputs .......................................................................... |
3-4 |
Differential Connection Considerations (DIFF Input Mode).......................... |
3-5 |
Differential Connections for Ground-Referenced Signal Sources.... |
3-6 |
Differential Connections for Nonreferenced |
|
or Floating Signal Sources ............................................................. |
3-7 |
Using Bias Resistors ........................................................... |
3-7 |
© National Instruments Corporation |
vii |
SCB-68 Shielded Connector Block User Manual |
Contents
Single-Ended Connection Considerations ...................................................... |
3-8 |
Single-Ended Connections for Floating Signal Sources |
|
(RSE Input Mode).......................................................................... |
3-9 |
Single-Ended Connections for Grounded Signal Sources |
|
(NRSE Input Mode)....................................................................... |
3-9 |
Connecting Analog Output Signals ............................................................................... |
3-10 |
Connecting Digital Signals............................................................................................ |
3-11 |
Connecting Timing Signals ........................................................................................... |
3-12 |
Noise Considerations..................................................................................................... |
3-13 |
Chapter 4
Using Thermocouples
Switch Settings and Temperature Sensor Configuration............................................... |
4-2 |
Special Considerations .................................................................................................. |
4-3 |
Chapter 5
Adding Components for Special Functions
Channel Pad Configurations.......................................................................................... |
5-2 |
Conditioning Analog Input Channels ............................................................. |
5-2 |
Conditioning Analog Output Channels........................................................... |
5-3 |
Conditioning PFI0/TRIG1 .............................................................................. |
5-4 |
Accuracy and Resolution Considerations...................................................................... |
5-5 |
Open Thermocouple Detection...................................................................................... |
5-5 |
Differential Open Thermocouple Detection ................................................... |
5-6 |
Single-Ended Open Thermocouple Detection ................................................ |
5-6 |
Sources of Error .............................................................................................. |
5-6 |
Lowpass Filtering .......................................................................................................... |
5-7 |
Theory of Operation........................................................................................ |
5-7 |
One-Pole Lowpass RC Filter .......................................................................... |
5-10 |
Selecting Components..................................................................................... |
5-11 |
Adding Components ....................................................................................... |
5-11 |
Single-Ended Lowpass Filter............................................................ |
5-12 |
Differential Lowpass Filter............................................................... |
5-12 |
Analog Output and Digital Input Lowpass Filtering ........................ |
5-12 |
Lowpass Filtering Applications ...................................................................... |
5-13 |
Noise Filtering .................................................................................. |
5-13 |
Antialiasing Filtering ........................................................................ |
5-13 |
Special Consideration for Analog Input Channels.......................................... |
5-14 |
Special Consideration for Analog Output Signals .......................................... |
5-14 |
Special Consideration for Digital Trigger Input Signals ................................ |
5-15 |
Measuring a 4 to 20 mA Current ................................................................................... |
5-16 |
Theory of Operation........................................................................................ |
5-16 |
SCB-68 Shielded Connector Block User Manual |
viii |
ni.com |
|
Contents |
Selecting a Resistor ......................................................................................... |
5-17 |
Adding Components........................................................................................ |
5-18 |
Single-Ended Inputs .......................................................................... |
5-18 |
Differential Inputs ............................................................................. |
5-18 |
Attenuating Voltage ....................................................................................................... |
5-18 |
Theory of Operation ........................................................................................ |
5-19 |
Selecting Components ..................................................................................... |
5-20 |
Accuracy Considerations .................................................................. |
5-20 |
Adding Components........................................................................................ |
5-20 |
Single-Ended Input Attenuators........................................................ |
5-20 |
Differential Input Attenuators ........................................................... |
5-21 |
Analog Output and Digital Input Attenuators................................... |
5-22 |
Special Considerations for Analog Input ........................................................ |
5-22 |
Special Considerations for Analog Output...................................................... |
5-23 |
Special Considerations for Digital Inputs........................................................ |
5-24 |
Appendix A
Specifications
Appendix B
Quick Reference Labels
Appendix C
Fuse and Power
Appendix D
SCB-68 Circuit Diagrams
Appendix E
Soldering and Desoldering on the SCB-68
Appendix F
Technical Support and Professional Services
Glossary
Index
© National Instruments Corporation |
ix |
SCB-68 Shielded Connector Block User Manual |
|
This manual describes the SCB-68 and explains how to use the connector |
|
block with National Instruments data acquisition (DAQ) devices. |
Conventions |
|
|
|
|
The following conventions appear in this manual: |
<> |
Angle brackets that contain numbers separated by an ellipsis represent a |
|
range of values associated with a bit or signal name—for example, |
|
DIO<3..0>. |
» |
The » symbol leads you through nested menu items and dialog box options |
|
to a final action. The sequence File»Page Setup»Options directs you to |
|
pull down the File menu, select the Page Setup item, and select Options |
|
from the last dialog box. |
|
This icon denotes a note, which alerts you to important information. |
|
This icon denotes a caution, which advises you of precautions to take to |
|
avoid injury, data loss, or a system crash. When this symbol is marked on |
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the device, refer to the Safety Information of Chapter 1, Introduction, for |
|
precautions to take. |
bold |
Bold text denotes items that you must select or click on in the software, |
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such as menu items and dialog box options. Bold text also denotes |
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parameter names. |
italic |
Italic text denotes variables, emphasis, a cross reference, or an introduction |
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to a key concept. This font also denotes text that is a placeholder for a word |
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or value that you must supply. |
monospace |
Text in this font denotes text or characters that you should enter from the |
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keyboard, sections of code, programming examples, and syntax examples. |
|
This font is also used for the proper names of disk drives, paths, directories, |
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programs, subprograms, subroutines, device names, functions, operations, |
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variables, filenames and extensions, and code excerpts. |
© National Instruments Corporation |
xi |
SCB-68 Shielded Connector Block User Manual |
About This Manual
For more information about using the SCB-68 with DAQ devices, refer to the following resources:
•DAQ device user manuals, at ni.com/manuals
•NI Developer Zone, at ni.com/zone
SCB-68 Shielded Connector Block User Manual |
xii |
ni.com |
1
Introduction
The SCB-68 is a shielded I/O connector block with 68 screw terminals for easy signal connection to a National Instruments 68or 100-pin DAQ device. The SCB-68 features a general breadboard area for custom circuitry and sockets for interchanging electrical components. These sockets or component pads allow RC filtering, 4 to 20 mA current sensing, open thermocouple detection, and voltage attenuation. The open component pads allow signal conditioning to be easily added to the analog input (AI) signals and to the DAC0OUT, DAC1OUT, and PFI0/TRIG1 signals of a 68-pin or 100-pin DAQ device.
To set up and use the SCB-68, you need the following items:
SCB-68 68-pin shielded connector block
One of the devices listed in Table 1-1
One of the device-compatible cables listed in Table 1-1
The device user manual or user guide, which you can access at ni.com/manuals
Phillips number 1 and number 2 screwdrivers
0.125 in. flathead screwdriver
Long-nose pliers
Wire cutters
Wire insulation strippers
Quick reference label for the DAQ device you are using
© National Instruments Corporation |
1-1 |
SCB-68 Shielded Connector Block User Manual |
Chapter 1 |
Introduction |
The following items, if you are adding components (optional):
–Soldering iron and solder
–Resistors
–Capacitors
A quick reference label for E Series devices is included in this kit. Quick reference labels for some other devices ship with the DAQ device itself. These labels show the switch configurations and define the screw terminal pinouts for compatible DAQ devices. You can put the label on the inside of the SCB-68 cover for easy reference if you are using one of these devices.
Refer to Appendix B, Quick Reference Labels, for the switch configurations and screw terminal pinouts that are included on each quick reference label.
Table 1-1 shows cabling options and features for DAQ devices that are compatible with the SCB-68. Figure 1-1 shows where to apply the quick reference label to the inside cover of the SCB-68.
Device |
Cable Assembly |
Features |
|
|
|
|
|
|
|
E Series Devices |
|
|
|
|
68-Pin Devices (except DAQCards) |
SH68-68-EP, |
Direct feedthrough only |
|
SH68-68-R1-EP, |
Thermocouple measurements |
|
R6868 |
Open thermocouple detection |
|
|
Current input |
|
|
Filtering |
|
|
Voltage dividers |
|
|
AC coupling |
|
|
|
100-Pin Devices |
SH1006868 |
Direct feedthrough only |
|
|
Thermocouple measurements |
|
|
Open thermocouple detection |
|
|
Current input |
|
|
Filtering |
|
|
Voltage dividers |
|
|
AC coupling |
|
|
|
SCB-68 Shielded Connector Block User Manual |
1-2 |
ni.com |
Chapter 1 Introduction
Table 1-1. Device-Specific Hardware Configuration (Continued)
Device |
Cable Assembly |
Features |
|
|
|
|
|
|
NI 6024E for PCMCIA |
SCH68-68-EP, |
Direct feedthrough only |
(DAQCard-6024E), |
RC68-68 |
Thermocouple measurements |
NI 6036E for PCMCIA |
|
Open thermocouple detection |
(DAQCard-6036E), |
|
Current input |
NI 6062E for PCMCIA |
|
Filtering |
(DAQCard-6062E) |
|
Voltage dividers |
|
|
AC coupling |
|
|
|
NI 6012E for PCMCIA |
PSHR68-68, |
Direct feedthrough only |
(DAQCard-AI-16XE-50), |
PR68-68F |
Thermocouple measurements |
NI 6041E for PCMCIA |
|
Open thermocouple detection |
(DAQCard-AI-16E-4) |
|
Current input |
|
|
Filtering |
|
|
Voltage dividers |
|
|
AC coupling |
|
|
|
|
Analog Output (AO) Devices |
|
|
|
|
NI 670X |
SH68-68-D1 |
Direct feedthrough only |
for PCI/PXI/CompactPCI |
R6868 |
RC filtering |
|
|
|
NI 671X/673X |
SH68-68-EP |
Direct feedthrough only |
for PCI/PXI/CompactPCI |
SH68-68-R1-EP |
RC filtering |
|
R6868 |
|
|
|
|
NI 6715 for PCMCIA |
SHC68-68-EP |
Direct feedthrough only |
(DAQCard-6715) |
RC6868 |
RC filtering |
|
|
|
|
Digital I/O (DIO) Devices |
|
|
|
|
NI 6533 |
SH68-68-D1 |
Direct feedthrough only |
for ISA/PCI/PXI/CompactPCI |
R6868 |
|
|
|
|
NI 6533 for PCMCIA |
PSHR68-68-D1, |
Direct feedthrough only |
(DAQCard-6533), |
PR6868F |
|
|
|
|
NI 6534 |
SH68-68-D1 |
Direct feedthrough only |
for PCI/PXI/CompactPCI |
R6868 |
|
|
|
|
|
Real-Time (RT) Devices |
|
|
|
|
NI 7030/6030E |
SH68-68-EP |
Direct feedthrough only |
for PCI/PXI/CompactPCI, |
SH68-68R1-EP, |
Thermocouple measurements |
NI 7030/6040E |
R6868 |
Open thermocouple detection |
for PCI/PXI/CompactPCI |
|
Current input |
|
|
Filtering |
|
|
Voltage dividers |
|
|
AC coupling |
|
|
|
NI 7030/6533 |
SH68-68-D1 |
Direct feedthrough only |
for PCI/PXI/CompactPCI |
R6868 |
|
|
|
|
© National Instruments Corporation |
1-3 |
SCB-68 Shielded Connector Block User Manual |
Chapter 1 Introduction
Table 1-1. Device-Specific Hardware Configuration (Continued)
Device |
Cable Assembly |
Features |
|
|
|
|
|
|
|
S Series Devices |
|
|
|
|
NI 6110/6111 for PCI |
SH68-68-EP |
Direct feedthrough only |
|
SH68-68R1-EP, |
|
|
R6868 |
|
|
|
|
NI 6115/6120 |
SH68-68-EP |
Direct feedthrough only |
for PCI/PXI/CompactPCI |
SH68-68R1-EP, |
|
|
R6868 |
|
|
|
|
|
Timing I/O (TIO) Devices |
|
|
|
|
NI 6601/6602 |
SH68-68-D1, |
Direct feedthrough only |
for PCI/PXI/CompactPCI |
R6868 |
|
|
|
|
|
Other Devices |
|
|
|
|
NI 250X |
SH68-68 |
Direct feedthrough only |
for PXI/CompactPCI |
|
|
|
|
|
NI 4350 for PCMCIA |
SH68-68 |
Not recommended for use with the |
(DAQCard-4350), |
|
SCB-68 |
NI 4350 for USB |
|
To maximize the available features, |
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|
|
|
|
NI recommends using this DAQ |
|
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device with the CB-68T, TBX-68, |
|
|
or TBX-68T terminal blocks. |
|
|
|
NI 4351 |
SH68-68 |
Not recommended for use with the |
for PCI/PXI/CompactPCI |
|
SCB-68 |
|
|
To maximize the available features, |
|
|
NI recommends using this DAQ |
|
|
device with the CB-68T, TBX-68, |
|
|
or TBX-68T terminal blocks. |
|
|
|
NI 445X for PCI |
SHC50-68 |
Direct feedthrough only |
|
|
|
NI 455X for PCI |
SHC50-68 |
Direct feedthrough only |
|
|
|
NI 5411 |
SHC50-68 |
Direct feedthrough only |
for PCI/PXI/CompactPCI |
|
|
|
|
|
NI 5431 |
SHC50-68 |
Direct feedthrough only |
for PCI/PXI/CompactPCI |
|
|
|
|
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SCB-68 Shielded Connector Block User Manual |
1-4 |
ni.com |
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Chapter 1 |
Introduction |
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1 |
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2 |
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3 |
9 |
10 |
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5 |
4 |
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6 |
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8 |
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7 |
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1 |
Quick Reference Label |
4 |
Lock Washers |
8 |
Strain-Relief Bars |
2 |
Cover |
5 |
Shielding Screws |
9 |
Strain-Relief Screws |
3 |
68-Pin Connector |
6 |
68-Pin I/O Connector |
10 |
Circuit Card Assembly |
|
Screws |
7 |
Base |
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|
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The following sections describe how to cable one or more SCB-68 connector blocks to a DAQ device using 68-pin or 100-pin cables.
Note For the I/O connector pinout of the DAQ device, refer to the device user manual at ni.com/manuals or to the quick reference label provided with the DAQ device.
Table 1-1 lists the 68-pin cable assemblies that can connect the SCB-68 to a 68-pin DAQ device. Each end of these 68-pin cables has a 68-pin I/O connector that you can connect to the SCB-68 and to the 68-pin DAQ device. In this configuration, the I/O connector pinout on the DAQ device determines the I/O connector pinout on the SCB-68.
© National Instruments Corporation |
1-5 |
SCB-68 Shielded Connector Block User Manual |
Chapter 1 |
Introduction |
Figure 1-2 shows how to use a 68-pin cable to connect the SCB-68 to a 68-pin DAQ device.
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1 |
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5 |
4 |
3 |
2 |
1 |
68-Pin Cable Assembly |
4 |
68-Pin I/O Connector |
2 |
68-Pin DAQ Device |
5 |
SCB-68 Connector Block |
3 |
68-Pin I/O Connector |
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You can use the SH1006868 cable assembly to connect two SCB-68 connector blocks to a 100-pin DAQ device. The SH1006868 is Y-shaped, with a 100-pin male connector on one end and two 68-pin female connectors on the opposite end. The DAQ device connects to the 100-pin cable connector, and an SCB-68 can connect to each 68-pin cable connector. Figure 1-3 shows how use the SH1006868 to cable a 100-pin DAQ device to two SCB-68 devices.
SCB-68 Shielded Connector Block User Manual |
1-6 |
ni.com |
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Chapter 1 |
Introduction |
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3 |
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2 |
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4 |
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1 |
SCB-68 Connector Blocks |
4 |
100-Pin DAQ Device |
2 |
68-Pin I/O Connectors |
5 |
100-Pin I/O Connector |
3 |
SH1006868 Cable Assembly |
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When you attach two SCB-68 devices to the SH1006868 cable, one of the SCB-68 connector blocks has a full 68-pin I/O connector pinout, and the other SCB-68 connector block has an extended AI or extended digital pinout. Each 68-pin end of the SH1006868 cable has a label that indicates which I/O connector pinout is associated with that 68-pin I/O connector.
Figure 1-4 shows the pin assignments for the I/O connector on a 68-pin E Series device. This connector is available when you use the SH68-68-EP or R6868 cable assemblies with an E Series DAQ device. It is also one of two 68-pin connectors available when you use the SH1006868 cable assembly with a 100-pin E Series DAQ device.
© National Instruments Corporation |
1-7 |
SCB-68 Shielded Connector Block User Manual |
Chapter 1 |
Introduction |
ACH8 |
34 |
68 |
ACH0 |
ACH1 |
33 |
67 |
AIGND |
AIGND |
32 |
66 |
ACH9 |
ACH10 |
31 |
65 |
ACH2 |
ACH3 |
30 |
64 |
AIGND |
AIGND |
29 |
63 |
ACH11 |
ACH4 |
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28 |
62 |
AISENSE |
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AIGND |
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27 |
61 |
ACH12 |
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ACH13 |
26 |
60 |
ACH5 |
ACH6 |
25 |
59 |
AIGND |
AIGND |
24 |
58 |
ACH14 |
ACH15 |
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23 |
57 |
ACH7 |
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DAC0OUT1 |
22 |
56 |
AIGND |
DAC1OUT1 |
21 |
55 |
AOGND2 |
EXTREF3 |
20 |
54 |
AOGND2 |
DIO4 |
19 |
53 |
DGND |
DGND |
18 |
52 |
DIO0 |
DIO1 |
17 |
51 |
DIO5 |
DIO6 |
16 |
50 |
DGND |
DGND |
15 |
49 |
DIO2 |
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+5V |
14 |
48 |
DIO7 |
DGND |
13 |
47 |
DIO3 |
DGND |
12 |
46 |
SCANCLK |
PFI0/TRIG1 |
11 |
45 |
EXTSTROBE* |
PFI1/TRIG2 |
10 |
44 |
DGND |
DGND |
9 |
43 |
PFI2/CONVERT* |
+5V |
8 |
42 |
PFI3/GPCTR1_SOURCE |
DGND |
7 |
41 |
PFI4/GPCTR1_GATE |
PFI5/UPDATE* |
6 |
40 |
GPCTR1_OUT |
PFI6/WFTRIG |
5 |
39 |
DGND |
DGND |
4 |
38 |
PFI7/STARTSCAN |
PFI9/GPCTR0_GATE |
3 |
37 |
PFI8/GPCTR0_SOURCE |
GPCTR0_OUT |
2 |
36 |
DGND |
FREQ_OUT |
1 |
35 |
DGND |
1No connect on the DAQCard-AI-16E-4, DAQCard-AI-16XE-50, NI PCI-6023E, NI PCI-6032E, NI PCI-6033E, and NI PCI-6034E
2No connect on the DAQCard-AI-16E-4 and DAQCard-AI-16XE-50
3No connect on the DAQCard-AI-16E-4, DAQCard-AI-16XE-50, DAQCard-6024E, NI PCI-6023E, NI PCI-6024E, NI PXI-6030E, NI PXI-6031E, NI PCI-6032E, NI PCI-6033E, NI PCI-6034E,
NI PCI-6035E, NI PCI-6036E, PCI-MIO-16XE-10, and PCI-MIO-16XE-50
SCB-68 Shielded Connector Block User Manual |
1-8 |
ni.com |
Chapter 1 |
Introduction |
Figure 1-5 shows the pin assignments for the extended AI connector. This pinout shows the other 68-pin connector when you use the SH1006868 cable assembly with an NI 6031E, NI 6033E, or NI 6071E.
ACH24 |
34 |
68 |
ACH16 |
ACH17 |
33 |
67 |
ACH25 |
ACH18 |
32 |
66 |
ACH26 |
ACH27 |
31 |
65 |
ACH19 |
ACH20 |
30 |
64 |
ACH28 |
ACH21 |
29 |
63 |
ACH29 |
ACH30 |
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28 |
62 |
ACH22 |
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ACH23 |
27 |
61 |
ACH31 |
ACH32 |
26 |
60 |
ACH40 |
ACH41 |
25 |
59 |
ACH33 |
ACH34 |
24 |
58 |
ACH42 |
ACH35 |
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23 |
57 |
ACH43 |
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AIGND |
22 |
56 |
AISENSE2 |
ACH44 |
21 |
55 |
ACH36 |
ACH37 |
20 |
54 |
ACH45 |
ACH38 |
19 |
53 |
ACH46 |
ACH47 |
18 |
52 |
ACH39 |
ACH48 |
17 |
51 |
ACH56 |
ACH49 |
16 |
50 |
ACH57 |
ACH58 |
15 |
49 |
ACH50 |
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ACH51 |
14 |
48 |
ACH59 |
ACH52 |
13 |
47 |
ACH60 |
ACH61 |
12 |
46 |
ACH53 |
ACH54 |
11 |
45 |
ACH62 |
ACH55 |
10 |
44 |
ACH63 |
NC |
9 |
43 |
NC |
NC |
8 |
42 |
NC |
NC |
7 |
41 |
NC |
NC |
6 |
40 |
NC |
NC |
5 |
39 |
NC |
NC |
4 |
38 |
NC |
NC |
3 |
37 |
NC |
NC |
2 |
36 |
NC |
NC |
1 |
35 |
NC |
NC = No Connect
© National Instruments Corporation |
1-9 |
SCB-68 Shielded Connector Block User Manual |
Chapter 1 |
Introduction |
Figure 1-6 shows the pin assignments for the extended digital connector. This pinout shows the other 68-pin connector when you use the SH1006868 cable assembly with an NI 6025E or the NI 6021E (AT-MIO-16DE-10) for ISA.
GND |
34 |
68 |
PC7 |
PC6 |
33 |
67 |
GND |
PC5 |
32 |
66 |
GND |
GND |
31 |
65 |
PC4 |
PC3 |
30 |
64 |
GND |
PC2 |
29 |
63 |
GND |
GND |
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28 |
62 |
PC1 |
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PC0 |
27 |
61 |
GND |
PB7 |
26 |
60 |
GND |
GND |
25 |
59 |
PB6 |
PB5 |
24 |
58 |
GND |
PB4 |
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23 |
57 |
GND |
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GND |
22 |
56 |
PB3 |
GND |
21 |
55 |
PB2 |
PB1 |
20 |
54 |
GND |
PB0 |
19 |
53 |
GND |
GND |
18 |
52 |
PA7 |
PA6 |
17 |
51 |
GND |
PA5 |
16 |
50 |
GND |
GND |
15 |
49 |
PA4 |
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PA3 |
14 |
48 |
GND |
PA2 |
13 |
47 |
GND |
GND |
12 |
46 |
PA1 |
PA0 |
11 |
45 |
GND |
+5V |
10 |
44 |
GND |
NC |
9 |
43 |
NC |
NC |
8 |
42 |
NC |
NC |
7 |
41 |
NC |
NC |
6 |
40 |
NC |
NC |
5 |
39 |
NC |
NC |
4 |
38 |
NC |
NC |
3 |
37 |
NC |
NC |
2 |
36 |
NC |
NC |
1 |
35 |
NC |
NC = No Connect
SCB-68 Shielded Connector Block User Manual |
1-10 |
ni.com |
Chapter 1 |
Introduction |
For instructions about using Measurement & Automation Explorer (MAX) to configure the SCB-68 as an accessory for a DAQ device, complete the following steps:
1.Navigate to MAX by selecting Start»Programs»National Instruments»Measurement&Automation.
2.Select Help»Help Topics»NI-DAQ in MAX.
3.Select DAQ Devices»Configuring DAQ Devices»Configuring DAQ Devices»Accessory in the Measurement & Automation Explorer Help for MAX.
The following section contains important safety information that you must follow when installing and using the SCB-68.
Do not operate the SCB-68 in a manner not specified in this document. Misuse of the SCB-68 can result in a hazard. You can compromise the safety protection built into the SCB-68 if the device is damaged in any way. If the SCB-68 is damaged, return it to NI for repair.
Do not substitute parts or modify the SCB-68 except as described in this document. Use the SCB-68 only with the chassis, modules, accessories, and cables specified in the installation instructions. You must have all covers and filler panels installed during operation of the SCB-68.
Do not operate the SCB-68 in an explosive atmosphere or where there may be flammable gases or fumes. Operate the SCB-68 only at or below the pollution degree stated in Appendix A, Specifications.
Pollution is foreign matter in a solid, liquid, or gaseous state that can reduce dielectric strength or surface resistivity. The following is a description of pollution degrees:
•Pollution Degree 1 means no pollution or only dry, nonconductive pollution occurs. The pollution has no influence.
•Pollution Degree 2 means that only nonconductive pollution occurs in most cases. Occasionally, however, a temporary conductivity caused by condensation must be expected.
© National Instruments Corporation |
1-11 |
SCB-68 Shielded Connector Block User Manual |
Chapter 1 |
Introduction |
•Pollution Degree 3 means that conductive pollution occurs, or dry, nonconductive pollution occurs that becomes conductive due to condensation.
Clean the SCB-68 with a soft nonmetallic brush. Make sure that the SCB-68 is completely dry and free from contaminants before returning it to service.
You must insulate signal connections for the maximum voltage for which the SCB-68 is rated. Do not exceed the maximum ratings for the SCB-68. Remove power from signal lines before connecting them to or disconnecting them from the SCB-68.
Operate the SCB-68 only at or below the installation category stated in
Appendix A, Specifications.
The following is a description of installation categories:
•Installation Category I is for measurements performed on circuits not directly connected to MAINS1. This category is a signal level such as voltages on a printed wire board (PWB) on the secondary of an isolation transformer.
Examples of Installation Category I are measurements on circuits not derived from MAINS and specially protected (internal) MAINS-derived circuits.
•Installation Category II is for measurements performed on circuits directly connected to the low-voltage installation. This category refers to local-level distribution such as that provided by a standard wall outlet.
Examples of Installation Category II are measurements on household appliances, portable tools, and similar equipment.
•Installation Category III is for measurements performed in the building installation. This category is a distribution level referring to hardwired equipment that does not rely on standard building insulation.
Examples of Installation Category III include measurements on distribution circuits and circuit breakers. Other examples of Installation Category III are wiring including cables, bus-bars, junction boxes, switches, socket outlets in the building/fixed
1MAINS is defined as the electricity supply system to which the equipment concerned is designed to be connected either for powering the equipment or for measurement purposes.
SCB-68 Shielded Connector Block User Manual |
1-12 |
ni.com |
Chapter 1 |
Introduction |
installation, and equipment for industrial use, such as stationary motors with a permanent connection to the building/fixed installation.
•Installation Category IV is for measurements performed at the source of the low-voltage (<1,000 V) installation.
Examples of Installation Category IV are electric meters, and measurements on primary overcurrent protection devices and ripple-control units.
Below is a diagram of a sample installation.
© National Instruments Corporation |
1-13 |
SCB-68 Shielded Connector Block User Manual |
2
Parts Locator and Wiring Guide
This chapter explains how to connect signals to the SCB-68.
The following cautions contain important safety information concerning hazardous voltages and terminal blocks.
Cautions Keep away from live circuits. Do not remove equipment covers or shields unless you are trained to do so. If signal wires are connected to the SCB-68, dangerous voltages may exist even when the equipment is powered off. To avoid dangerous electrical shock, do not perform procedures involving cover or shield removal unless you are qualified to do so. Before you remove the cover, disconnect the AC power or any live circuits from the SCB-68.
The chassis GND terminals are for grounding high-impedance sources such as floating sources (1 mA maximum). Do not use these terminals as safety earth grounds.
Do not connect high voltages to the SCB-68 even with an attenuator circuit. Never connect voltages ≥42 Vrms. NI is not liable for any damage or injuries resulting from improper use or connection.
© National Instruments Corporation |
2-1 |
SCB-68 Shielded Connector Block User Manual |
Chapter 2 Parts Locator and Wiring Guide
1 |
2 |
3 |
4 |
C6 |
R20 |
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R21 |
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C4 |
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R22(A) |
S5 S4 S3 |
33 34 |
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R4(F) |
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RC12(B) |
RC4(E) |
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R23(C) |
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RC13(D) |
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R5(G) |
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R24(A) |
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R6(F) |
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RC14(B) |
RC5(E) |
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R25(C) |
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RC15(D) |
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R7(G) |
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R26(A) |
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R8(F) |
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RC16(B) |
RC6(E) |
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R27(C) |
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RC17(D) |
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R9(G) |
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R28(A) |
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R10(F) |
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RC18(B) |
RC7(E) |
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R29(C) |
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C5 |
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RC19(D) |
R11(G) |
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13 |
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C3 |
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R38 |
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R30(A) |
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R12(F) |
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RC20(B) |
RC8(E) |
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R31(C) |
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RC21(D) |
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R13(G) |
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R32(A) |
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R14(F) |
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RC22(B) |
RC9(E) |
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R33(C) |
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RC23(D) |
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R15(G) |
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R34(A) |
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R16(F) |
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RC24(B) |
RC10(E) |
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R35(C) |
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RC25(D) |
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R17(G) |
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R36(A) |
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R18(F) |
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RC26(B) |
RC11(E) |
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R37(C) |
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RC27(D) |
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R19(G) |
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SCB-68
©COPYRIGHT 1993
J1
68
34
67
33
66
32
65
31
64
30
63
29
62
28
61
27
60
26
59
25
58
24
57
23
1 3
12
46
13
47
14
48
15
49
16
50
17
51
18
52
19
53
20
54
21
55
22
56
XF1
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C2 |
C1 |
S1 |
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S2 |
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1 |
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35 |
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2 |
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36 |
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3 |
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37 |
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4 |
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38 |
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5 |
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39 |
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6 |
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40 |
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7 |
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41 |
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8 |
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42 |
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RC2 |
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9 |
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43 |
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R2 |
RC1 |
R10 |
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10 |
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RC3 |
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44 |
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R3 |
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45 |
B.REV 01-ASSY182470
S/N
5
6
7 |
8
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12 |
11 |
10 |
9 |
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1 |
Pads R20 and R21 |
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8 |
Serial Number |
2 |
Switches S3, S4, and S5 |
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9 |
RC Filters and Attenuators for DAC0, |
3 |
68-Pin I/O Connector |
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DAC1, and TRIG1 |
4 |
Fuse (0.8 A) |
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10 |
Breadboard Area |
5 |
Switches S1 and S2 |
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11 |
Temperature Sensor |
6 |
Assembly Number and Revision Letter |
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12 |
Product Name |
7 |
Screw Terminals |
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13 |
Pads for AI Conditioning |
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SCB-68 Shielded Connector Block User Manual |
2-2 |
ni.com |
Chapter 2 Parts Locator and Wiring Guide
To connect signals to the SCB-68, complete the following steps while referring to Figure 1-1, SCB-68 Parts Locator Diagram, and to Figure 2-1.
1.Disconnect the 68-pin cable from the SCB-68, if it is connected.
2.Remove the shielding screws on either side of the top cover with a Phillips-head number 1 screwdriver. You can now open the box.
3.Configure the switches and other options relative to the types of signals you are using.
4.Loosen the strain-relief screws with a Phillips-head number 2 screwdriver. Slide the signal wires through the front panel strain-relief opening. You can also remove the top strain-relief bar if you are connecting many signals. Add insulation or padding if necessary.
5.Connect the wires to the screw terminals by stripping off 0.25 in. of the insulation, inserting the wires into the green terminals, and tightening the screws.
6.Reinstall the strain-relief bar (if you removed it) and tighten the strain-relief screws.
7.Close the top cover.
8.Reinsert the shielding screws to ensure proper shielding.
You can now connect the SCB-68 to the 68-pin I/O connector.
The SCB-68 has five switches that must be properly configured to use the SCB-68 with the DAQ device. Table 2-1 illustrates the available switch configurations and the affected signals for each switch setting. Refer to Table 2-1 to determine the switch setting that applies to your application, and then refer to the following sections for more information on specific types of signals.
© National Instruments Corporation |
2-3 |
SCB-68 Shielded Connector Block User Manual |
Chapter 2 Parts Locator and Wiring Guide
Switch Setting |
Applicable Signals |
Analog input, analog output,
digital I/O, and timing I/O
Temperature Sensor
S5 S4 S3
Signal Conditioning
Circuitry Power (Off)
S1
S2
Direct feedthrough, with temperature sensor disabled and accessory power disabled
Analog input
and analog output1
Temperature Sensor
S5 S4 S3
Signal Conditioning
Circuitry Power (On)
S1
S2
Temperature sensor disabled, and accessory power enabled2
Note: This configuration is the factory-default configuration.
SCB-68 Shielded Connector Block User Manual |
2-4 |
ni.com |
Chapter 2 Parts Locator and Wiring Guide
Table 2-1. Switch Configurations and Affected Signals (Continued)
Switch Setting |
Applicable Signals |
Single-ended analog input3
Temperature Sensor
S5 S4 S3
Signal Conditioning
Circuitry Power (On)
S1
S2
Single-ended temperature sensor, with accessory power enabled2
Differential analog input
Temperature Sensor
S5 S4 S3
Signal Conditioning
Circuitry Power (On)
S1
S2
Differential temperature sensor, with accessory power enabled2
1When accessory power is enabled, I/O pin 8 is fused and is intended to be connected to +5V. This setting is not recommended for use with the NI 653X, NI 670X, or NI 660X. Refer to the device user manual at ni.com/manuals to determine if the device supplies +5 V to I/O pin 8.
2Only applies to the signal conditioning circuitry.
3Except NI 61XX devices. Refer to the device user manual at ni.com/manuals to determine if the device supports single-ended inputs.
© National Instruments Corporation |
2-5 |
SCB-68 Shielded Connector Block User Manual |
3
Connecting Signals
This chapter describes the types of signal sources that you use when configuring the channels and making signal connections to the SCB-68, describes input modes, and discusses noise considerations to help you acquire accurate signals.
The following sections describe how to connect signal sources for single-ended or differential (DIFF) input mode. On most devices, you can software-configure the DAQ device channels for two types of single-ended connections—nonreferenced single-ended (NRSE) input mode and referenced single-ended (RSE) mode. RSE input mode is used for floating signal sources. In this case, the DAQ device provides the reference ground point for the external signal. NRSE input mode is used for ground-referenced signal sources. In this case, the external signal supplies its own reference ground point, and the DAQ device should not supply one.
Note Some devices might only support one of the possible input modes.
You can configure the DAQ device for one of three input modes—NRSE, RSE, or DIFF. The following sections discuss the use of single-ended and differential measurements and considerations for measuring both floating and ground-referenced signal sources. On devices that support both single-ended and DIFF input modes, using DIFF input mode commits two channels, ACH<i> and ACH<i+8>, to each signal. Figure 3-1 summarizes the recommended input modes for both types of signal sources.
© National Instruments Corporation |
3-1 |
SCB-68 Shielded Connector Block User Manual |
Chapter 3 Connecting Signals
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Signal Source Type |
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Floating Signal Source |
Grounded Signal Source |
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(Not Connected to Building Ground) |
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Examples: |
Examples: |
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• Ungrounded thermocouples |
• Plug-in instruments with |
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Input |
• |
Signal conditioning with |
nonisolated outputs |
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Isolated outputs |
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• |
Battery devices |
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ACH(+) |
+ |
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ACH(+) |
+ |
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+ |
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V1 |
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+ |
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V1 |
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ACH(–) |
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ACH(–) |
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– |
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– |
– |
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– |
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Differential |
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R |
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(DIFF) |
Common- |
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Common- |
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+ |
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+ |
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Mode |
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AIGND |
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Mode |
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AIGND |
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Voltage |
– |
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Voltage |
– |
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Refer to the Using Bias Resistors |
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section for information on bias resistors. |
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NOT RECOMMENDED |
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ACH |
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+ |
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ACH |
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+ |
V1 |
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+ |
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+ |
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V1 |
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– |
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– |
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AIGND |
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+ |
Vg |
– |
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Single-Ended — |
– |
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– |
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Ground |
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Common- |
+ |
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Referenced |
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Mode |
– |
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AIGND |
(RSE) |
CommonMode - + |
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Voltage |
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Voltage – |
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Ground-loop losses, Vg, are added to |
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measured signal. |
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ACH |
+ |
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ACH |
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+ |
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+ |
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V1 |
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+ |
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V1 |
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AISENSE |
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AISENSE |
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– |
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– |
– |
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– |
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Single-Ended — |
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Nonreferenced |
Common- |
+ |
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R |
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Common- |
+ |
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(NRSE) |
Mode |
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AIGND |
Mode |
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AIGND |
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Voltage |
– |
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Voltage |
– |
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Refer to the Using Bias Resistors section for information on bias resistors.
SCB-68 Shielded Connector Block User Manual |
3-2 |
ni.com |