© National Instruments | 2-3
X Series User Manual
Calibration Circuitry
The X Series analog inputs and outputs have calibration circuitry to correct gain and offset 
errors. You can calibrate the device to minimize AI and AO errors caused by time and 
temperature drift at run time. No external circuitry is necessary; an internal reference ensures 
high accuracy and stability over time and temperature changes.
Factory-calibration constants are permanently stored in an onboard EEPROM and cannot be 
modified. When you self-calibrate the device, as described in the Device Self-Calibration 
section of Chapter 1, 
Getting Started, software stores new constants in a user-modifiable section 
of the EEPROM. To return a device to its initial factory calibration settings, software can copy 
the factory-calibration constants to the user-modifiable section of the EEPROM. Refer to the 
NI-DAQmx Help or the LabVIEW Help for more information about using calibration constants.
For a detailed calibration procedure for X Series devices, refer to the DAQ Multifunction I/O 
(MIO) and Simultaneous Multifunction I/O (SMIO) Devices Calibration Procedure available at 
ni.com/manuals.
Cables and Accessories
Caution For compliance with Electromagnetic Compatibility (EMC) 
requirements, this product must be operated with shielded cables and accessories. If 
unshielded cables or accessories are used, the EMC specifications are no longer 
guaranteed unless all unshielded cables and/or accessories are installed in a shielded 
enclosure with properly designed and shielded input/output ports.
NI offers a variety of products to use with X Series PCI Express, PXI Express, USB devices, 
including cables, connector blocks, and other accessories, as follows:
• Shielded cables and cable assemblies, and unshielded ribbon cables and cable assemblies
• Screw terminal connector blocks, shielded and unshielded
• RTSI bus cables
• SCXI modules and accessories for isolating, amplifying, exciting, and multiplexing 
signals; with SCXI you can condition and acquire up to 3,072 channels
• Low-channel-count signal conditioning modules, devices, and accessories, including 
conditioning for strain gauges and RTDs, simultaneous sample and hold circuitry, and 
relays
For more specific information about these products, refer to the document, 63xx Models : DAQ 
Multifunction I/O Cable and Accessory Compatibility, available at ni.com/manuals.
Refer to the 
Custom Cabling and Connectivity section of this chapter and the Field Wiring 
Considerations
 section of Chapter 4, Analog Input, for information about how to select 
accessories for your X Series device.