Cabling Part Number (P/N), Link, and Pinout
Here is more detailed information about the differences between the SHC68-C68-RDIO2 vs SHC68-68-RDIO for R Series Devices
For more information about the Benefits of Using the RMIO and RDIO Cables as opposed to other cables
Connector Block Part Number (P/N), User Guide/Specifications, and Dimensional Drawings
Note that the pinouts for the SCB-68 and SCB-68A are different if you are using these devices with an NI 78xx R series module, and even have differences between the specific NI 78xx R series models. You can find a quick reference guide linked below for both of these connector block. It is suggested that you print out the pinout appropriate for your NI 78xx R Series Device and attach it to the inside cover of your connector clock.
The SCB-68 HSDIO has the correct pinout for those NI 78xx R Series devices that utilize it.
The SCB-68 and SCB-68A are functionally equivalent, with some improvements and small changes to the SCB-68A. So any of the above devices that call out the SCB-68A could be replaced with the SCB-68 with no functional differences. For more information on the connector blocks please visit their product documentation pages in the DAQ Accessory Guide and Digital Instrument Accessory Guide.
The NI-9151 CompactRIO R Series Expansion Chassis connects directly to any digital connector on NI 78xx R Series devices and houses up to four C Series I/O modules for industrial signal conditioning, I/O channel expansion, and direct sensor connectivity. This expansion chassis is not compatible with all NI 78xx R series modules/connectors.
Listed here are the links to the NI 9151 Product Page & NI 9151 User Manual and Specifications
The Expansion System is compatible with the DIO connector on the following modules:
||Number of 9151's
||Total CompactRIO I/O Modules