National Instruments PCI-6238, User Manual

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Chapter 2 DAQ System Overview
NI 6238/6239 User Manual 2-4 ni.com
Cables and Accessories
NI offers a variety of products to use with NI 6238/6239 devices, including
cables, connector blocks, and other accessories, as follows:
• Cables and cable assemblies
– Shielded
– Unshielded ribbon
• Screw terminal connector blocks, shielded and unshielded
• RTSI bus cables
For more specific information about these products, refer to
ni.com
.
Refer to the Custom Cabling section of this chapter, the Field Wiring
Considerations section of Chapter 4, Analog Input , and Appendix A,
Device-Specific Information , for information on how to select accessories
for your M Series device.
Custom Cabling
NI offers cables and accessories for many applications. However, if you
want to develop your own cable, the following kits can assist you:
• TB-37F-37SC —37-pin solder cup terminals, shell with strain relief
• TB-37F-37CP —37-pin crimp & poke terminals, shell with strain
relief
Also, adhere to the following guidelines for best results:
• For AI signals, use shielded, twisted-pair wires for each AI pair of
differential inputs. Connect the shield for each signal pair to the ground
reference at the source.
• Route the analog lines separately from the digital lines.
• When using a cable shield, use separate shields for the analog and
digital sections of the cable. Failure to do so results in noise coupling
into the analog signals from transient digital signals.
For more information on the connectors used for DAQ devices, refer to the
KnowledgeBase document,
Specifications and Manufacturers for Board
Mating Connectors , by going to
ni.com/info
and entering the info code
rdspmb
.