Measurement Specialties manual Calibrating the USB-1616HS-2, Chapter

Chapter 4

Calibrating the USB-1616HS-2

Every range of a USB-1616HS-2 device is calibrated at the factory using a digital NIST traceable calibration method. This method works by storing a correction factor for each range on the unit at the time of calibration. For analog inputs, the user can adjust the calibration of the board while it is installed in the acquisition system without destroying the factory calibration supplied with the board. This is accomplished by having two distinct calibration tables in the USB-1616HS-2 on-board EPROM—one which contains the factory calibration, and the other which is available for field calibration.

You can perform field calibration automatically in seconds with InstaCal and without the use of external hardware or instruments.

Field calibration derives its traceability through an on-board reference which has a stability of 0.005% per year.

Note that a two-year calibration period is recommended for USB-1616HS-2 boards. You should calibrate the USB-1616HS-2 using InstaCal after the board has fully warmed up. The recommended warm-up time is 30 minutes. For best results, calibrate the board immediately before making critical measurements. The high resolution analog components on the board are somewhat sensitive to temperature. Pre-measurement calibration ensures that your board is operating at optimum calibration values.

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