National Instruments SCC-68 User manual

USER GUIDE
SCC-68
I/O Connector Block with 4 SCC Signal Conditioning Slots for DAQ Devices
The SCC-68 is an I/O connector block for easy signal connection to a
National Instruments M Series or E Series DAQ device. The SCC-68
features screw terminals and a general breadboard area for I/O signal
connection, and bus terminals for external power and grounding. The
SCC-68 has four SCC slots for use in integrating thermocouple, strain
gauge, RTD input, frequency input, current input, voltage attenuator,
lowpass filter, load cell input, accelerometer, feedthrough, SPDT relay,
isolated digital I/O, and isolated voltage input SCC modules into the
measurement system.
Contents
Conventions ............................................................................................ 3
Using the SCC-68 Enclosure .................................................................. 4
Opening the Enclosure..................................................................... 4
Closing the Enclosure ...................................................................... 5
Stacking and Wall Mounting ........................................................... 6
Installing Rubber Feet...................................................................... 7
Connecting to the DAQ Device .............................................................. 8
Using the SCC-68 with 16 AI Channel M Series Devices .............. 8
Using the SCC-68 with 32 AI Channel M Series Devices .............. 8
Using the SCC-68 with a 68-Pin E Series Device ........................... 9
Using the SCC-68 with the NI 6025E, NI 6033E, or NI 6071E...... 10
SCC-68 Features ..................................................................................... 11
Screw Terminals .............................................................................. 12
Device Pinouts .......................................................................... 12
Wiring to Screw Terminals....................................................... 12
Integrated Strain Relief.................................................................... 12
SCC Modules................................................................................... 13
Breadboard Area .............................................................................. 13
Using the Temperature Sensor for Cold-Junction
Compensation (CJC) ..................................................................... 14
Cold Junction Temperature Measurement Accuracy ............... 15

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Bus Terminals...................................................................................15
Power Supply....................................................................................16
Using SCC Modules with the SCC-68 ....................................................16
Supported SCC Modules ..................................................................17
Connecting Signals to SCC Modules in the SCC-68 .......................17
Power Supply Considerations...........................................................19
LED ...........................................................................................20
Installing the SCC Modules in the SCC-68......................................21
SCC Connector Pinouts.............................................................21
Direct Access to SCC signals....................................................23
Analog Input Measurement Considerations ............................................23
Differential .......................................................................................24
Single-Ended ....................................................................................24
Non-Referenced Single Ended (NRSE) ...........................................25
Grounded Signal Sources ..........................................................25
Floating Signal Sources.............................................................26
Ground-Referenced Single Ended (RSE).........................................26
Grounded Signal Sources ..........................................................26
Floating Signal Sources.............................................................26
Taking Measurements with NI-DAQmx .................................................27
Configuring the SCC-68...................................................................28
Configuring the SCC-68 as an SCC Carrier..............................28
Configuring the SCC-68 as a Screw Terminal Accessory ........28
Configuring Channels and Tasks......................................................29
Configure a Task .......................................................................29
Configure Global Virtual Channels...........................................31
Using Your Task in an Application..................................................32
Specifications...........................................................................................33
Quick Reference Guides ..........................................................................38

©National Instruments Corporation 3 SCC-68 User Guide
Conventions
The following conventions are used 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,
AO <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
the product, refer to the Read Me First: Safety and Radio-Frequency
Interference document, shipped with the product, for precautions to take.
When symbol is marked on a product, it denotes a warning advising you to
take precautions to avoid electrical shock.
When symbol is marked on a product, it denotes a component that may be
hot. Touching this component may result in bodily injury.
bold Bold text denotes items that you must select or click in the software, such
as menu items and dialog box options. Bold text also denotes parameter
names.
italic Italic text denotes variables, emphasis, a cross-reference, or an introduction
to a key concept. Italic text also denotes text that is a placeholder for a word
or value that you must supply.
monospace Text in this font denotes text or characters that you should enter from the
keyboard, sections of code, programming examples, and syntax examples.
This font is also used for the proper names of disk drives, paths, directories,
programs, subprograms, subroutines, device names, functions, operations,
variables, filenames, and extensions.
SCC-XX This name refers to any SCC module.

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Using the SCC-68 Enclosure
Caution Refer to the Read Me First: Safety and Radio-Frequency Interference document
before removing equipment covers or connecting/disconnecting any signal wires.
Figure 1. SCC-68 Parts Locator Diagram
Opening the Enclosure
To open the SCC-68, use a flathead screwdriver to loosen the captive screw
at the front of the device. After the screw is loosened, pull up on the front
of the enclosure cover to open. The top half of the SCC-68 enclosure can
be removed completely.
1SCCSlots
2 Screw Terminals
3 68-Pin I/O Connector
4EnclosureCover
5 Quick Reference Guide
6 Enclosure Base
7 External Power Screw Terminal
8 External Power Switch
9 Strain Relief Wire Entry
4
5
6
3
2
2
1
8
7
9

©National Instruments Corporation 5 SCC-68 User Guide
Closing the Enclosure
To close the SCC-68, align the two back tabs into the corresponding holes
at the back of the base, as shown in the detail in Figure 2. With the cover
and base of the enclosure aligned, snap the SCC-68 closed. To secure the
SCC-68 enclosure, use a flathead screwdriver to push the screw down
against the spring resistance and tighten the screw.
Caution The captive screw must be used to secure the enclosure when connecting
hazardous voltage (>30 Vrms/42.4 Vpk/60 VDC) signals to an SCC-RLY01 module.
Note For safest operation of the SCC-68, NI recommends always using the captive screw
to keep the SCC-68 in a closed position.
Figure 2. SCC-68 Enclosure Features
1 Strain Relief Posts
2 Snapping Latches
3 Captive Screw
4 Hinge Tabs
5 Strain-Relief Holes for Cable Ties
4
1
5
2
3

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Stacking and Wall Mounting
The SCC-68 has grooves on the bottom of the enclosure that allow the
device to be stacked on top of other SCC-68 connector blocks.
Note The SCC-68 cannot be securely stacked onto another SCC-68 if the rear rubber feet
are attached.
The SCC-68 also has mounting holes on the bottom of the device for secure
wall-mounting. The third mounting hole allows you to mount the SCC-68
onto a wall sideways or inverted. Refer to Figures 3 and 4 for more
information about the location and use of these enclosure features.
Figure 3. SCC-68 Mounting Dimensions
1 Mounting Holes
2 Directional Mounting Hole
3 I/O Connector Cable
24.46 cm
(9.63 in.)
17.78 cm
(7.00 in.)
17.78 cm
(7.00 in.)
12.70 cm
(5.00 in.) 2.54 cm
(1.00 in.)
12.70 cm
(2.50 in.)
3.51 cm
(1.38 in.)
1
2
3

©National Instruments Corporation 7 SCC-68 User Guide
Installing Rubber Feet
Rubber non-skid feet are shipped with the device that can be attached for
secure desktop use. To install the rubber feet, remove adhesive backing and
affix to the SCC-68 where indicated in Figure 4.
Figure 4. SCC-68 Mounting Features
1 Rubber Feet
2 Wall-Mounting Holes
3 Stacking Grooves
21
3
1
1
2

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Connecting to the DAQ Device
The following sections describe how to connect the SCC-68 to the DAQ
device. The SCC-68 is designed to be used with M Series and E Series
DAQ devices only. Other 68-pin devices may not function properly with
the SCC-68.
Using the SCC-68 with 16 AI Channel M Series Devices
To use the SCC-68 with a 16 AI channel M Series device, complete the
following steps:
1. Attach the quick reference guide, shown in Figures 21 and 22, to the
top of the SCC-68 enclosure as shown in Figure 1. The quick reference
guide for Connector 0 (included in the SCC-68 kit) shows the pin
assignments of the SCC-68 and other useful information.
2. Attach the SCC-68 to the DAQ device using one of the following
cables:
• SHC68-68-EPM
• SHC68-68
• RC68-68
3. Proceed to the Taking Measurements with NI-DAQmx section for
information about using the SCC-68 in measurement applications.
Note Some M Series devices are available with a 37-pin connector. The SCC-68 cannot
be used with these devices.
Using the SCC-68 with 32 AI Channel M Series Devices
The 32 AI channel M Series DAQ device has two connectors.
• Connector 0 (AI 0-15)
• Connector 1 (AI 16-31)
The SCC-68 can be used with Connector 0 or Connector 1.
To use the SCC-68 with a 32 AI channel M Series device using
Connector 0, complete the following steps:
1. Attach the quick reference guide, shown in Figures 21 and 22, to the
top of the SCC-68 enclosure as shown in Figure 1. The quick reference
guide for Connector 0 (included in the SCC-68 kit) shows the pin
assignments of the SCC-68 and other useful information.

©National Instruments Corporation 9 SCC-68 User Guide
2. Attach the SCC-68 to Connector 0 of the DAQ device using one of the
following cables:
• SHC68-68-EPM
• SHC68-68
• RC68-68
3. Proceed to the Taking Measurements with NI-DAQmx section for
information about using the SCC-68 in measurement applications.
To use the SCC-68 with a 32 AI channel M Series device using
Connector 1, complete the following steps:
1. Attach the SCC-68 to Connector 1 of the DAQ device using one of the
following cables:
• SHC68-68-EPM
• SHC68-68
• RC68-68
2. Refer to Figure 22 in the Quick Reference Guides section for the quick
reference guide for the SCC-68 connected to Connector 1 of the DAQ
device. The guide shows the pin assignments of the SCC-68 and other
useful information. Attach a copy of this guide to the top of the
SCC-68 enclosure as shown in Figure 1.
Using the SCC-68 with a 68-Pin E Series Device
To use the SCC-68 with a 68-pin E Series device, complete the following
steps:
1. Attach the SCC-68 to the DAQ device using one of the following
cables:
• SH68-68-EP
• R68-68
2. Refer to Figure 23 in the Quick Reference Guides section for the quick
reference guide for the SCC-68 connected to the E Series DAQ device.
The guide shows the pin assignments of the SCC-68 and other useful
information. Attach a copy of this guide to the top of the SCC-68
enclosure as shown in Figure 1.

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Using the SCC-68 with the NI 6025E, NI 6033E, or NI 6071E
To use the SCC-68 with the NI 6025E, NI 6033E, or NI 6071E, complete
the following steps:
1. Attach the SCC-68 to the DAQ device using an SH1006868 cable. This
cable has two 68-pin connectors labeled MIO 16 and Extended I/O.
Connect the MIO 16 connector to the SCC-68. Refer to Figure 5.
Figure 5. Connecting a 100-Pin DAQ Device to an SCC-68 Connector Block and
Another Terminal Block
You cannot use the Extended I/O connector with an SCC-68. Use
another terminal block such as the SCB-68 or CB-68LPR with the
Extended I/O connector.
2. Refer to Figure 23 in the Quick Reference Guides section for the quick
reference guide for the SCC-68 connected to the E Series DAQ device.
The guide shows the pin assignments of the SCC-68 and other useful
information. Attach a copy of this pinout to the top of the SCC-68
enclosure as shown in Figure 1.
E Series
100-Pin Device
SH1006868 Cable
SCC-68
Extended
I/O Connector
MIO Connector
SCB-68 or
Other
Terminal
Block