The NI 4300, NI 4309, NI 4310, and NI 4340 use software calibration to adjust the software scaling of signals read from and produced by your device. Using onboard calibration pulse-width modulated (PWM) sources and an external reference voltage, your device calculates scaling constants for analog input. The scaling constants are stored in nonvolatile memory (EEPROM) on your device. NI recommends that you self-calibrate your device just before a measurement session but after your computer and the device have been powered on and warmed up for at least 15 minutes. You should allow this same warm-up time before performing any calibration of your system. Frequent calibration produces the most stable and repeatable measurement performance. The device is not harmed in any way if you recalibrate it often.

Note
  • Calibrating your device takes some time. Do not be alarmed if the Self-Calibrate or Adjust 4300 Calibration function/VI takes several minutes to execute.
  • For best results, stop any ongoing tasks and disconnect any unnecessary external connections before running calibration.

The NI 4302/4303/4304/4305, NI 4322, NI 433x, NI 4353, and NI 4357 do not self-calibrate or automatically calibrate. You must use a manual procedure to calibrate NI 4302/4303/4304/4305, NI 4322, NI 433x, NI 4353, and NI 4357 devices.