This guide addresses many common questions for the SCB-68 HSDIO breakout connector or terminal blocks, which allow you to easily interface digital input and output signals. Whether you need mounting information, mappings or pinouts for wiring, or creating custom configuration this guide will provide a short summary, and then link to other resources like manuals, specifications, dimensional drawings, and more.
This guide is intended to cover the SCB-68 HSDIO 68-pin terminal blocks which are designed for use with NI Digital and some R Series devices. It does not cover the similar SCB-68 and SCB-68A terminal blocks.
Quick Specifications, Manuals, Quick Reference Labels, and Dimensional Drawings
This section contains a summary of information frequently sought when installing, wiring up or configuring the SCB-68 HSDIO. More detailed information can be found in the linked additional resources below. Dimensional drawings can be downloaded for free and are available in 2D and 3D formats; they contain size measurements and other helpful information, and are available in several popular formats, such as PDF, AutoCAD (.dxf, and .igs (IGES)), STEP (.stp), and .prt (Pro/E).
SCB-68 HSDIO Quick Specifications and Published Resources
To easily wire sensors and signals to your terminal block, leverage the published documentation and information in this guide. Here are the basic steps to designing your measurement circuit diagram, understanding pin mapping, connecting your wiring, and configuring your terminal block. Failure to set up your terminal block properly may lead to no readings, unexpected readings, noisy readings, or possible damage to your terminal block, device, or module.
The general concepts of pin mapping and pinouts are covered in the Digital Instrument Accessory Guide Main Page. Note, a common point of confusion for normal wiring is the need to first understand the cable mapping, or pinout at the connector found on your terminal block, which is not the case.
The Connection Guide and Specifications for the SCB-68 HSDIO are provided in the Quick Specifications and Published Resources section above. These contain pinout or pin mappings, guidance on how to populate the optional SMB Connectors, and also extended information for configuring your terminal block in the various modes that it supports, and extending its functionality.
It is also important to consider using shielded signal wires, shielded cables, and ensuring that the terminal block itself has been correctly grounded. National Instruments recommends using 50 Ω cables for all signal connections. If you do not use 50 Ω cables, your application may be affected by signal reflections. You can limit the amplitude of signal reflections by terminating output lines with Schottky diodes. For more information terminating Output Lines with Schottky diodes see the Connection Guide provided in the Quick Specifications and Published Resources section above .
The breadboard on your SCB-68 HSDIO can be used to add SMB connectors The Connection Guide referenced contains detailed information on when to do these setups, how to configure them, and other details like soldering and desoldering information.
Once you've completed your wiring, make sure to finish by tightening the strain relief bar to ensure that your wires can not easily pull out from your terminal block.
Compatible Devices, Modules, and Cabling for the SCB-68 HSDIO
Some devices and modules listed in the table have extended compatibility information, which is linked to in their Compatibility Guide. Refer to your device or module's user manual or user guide for more information.
Device or Module
NI High-Speed Digital I/O (HSDIO) or Digital Waveform Instruments