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

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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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Contents Page USB-1616HS-2 Management committed to your satisfaction Trademark and Copyright Information Table of Contents USB-1616HS-2 Users Guide Where to find more information About this Users GuideWhat you will learn from this users guide Conventions used in this users guideOverview USB-1616HS-2 features Software featuresIntroducing the USB-1616HS-2 ChapterInstalling the USB-1616HS-2 TR-2U power supply and CA-1* line cordWhat comes with your USB-1616HS-2 shipment? HardwareInstalling the software Unpacking the USB-1616HS-2Additional documentation CA-96A expansion cableInstalling the hardware Configuring the hardware Connecting the board for I/O operationsConnectors, cables main I/O connector Information on signal connectionsScrew terminal pin outs USB-1616HS-2 screw terminal pin out single-ended connectionsDSUB25F expansion connector DSUB25 expansion connector pin outCabling CA-96A expansion cableFunctional Details USB-1616HS-2 componentsExternal power connector USB-1616HS-2 components rear viewUSB-1616HS-2 block diagram USB-1616HS-2 functional block diagramAnalog input Analog input scanningSettling time Example Analog channel scanning of voltage inputsExample Analog and digital scanning, once per scan mode Analog and digital scanning, once per scan mode exampleAnalog and digital scanning, once per scan mode example Tips for making accurate temperature measurements Thermocouple inputShielding AveragingAnalog output Digital I/O TriggeringDigital input scanning Digital outputs and pattern generationSoftware-based triggering Hardware analog triggeringDigital triggering Pre-triggering and post-triggering modes Counter inputsStop trigger modes Totalize mode Tips for making high-speed counter measurements 1 MHzMapped channels Counter modesDebounce modes Trigger after stable mode Trigger before stable modeDebounce mode comparisons Debounce module Trigger before stable modeEncoder mode Optimal debounce time for trigger before stable modeRepresentation of rotary shaft quadrature encoder Connecting the USB-1616HS-2 to an encoder Maximizing encoder accuracyTimer output frequency examples Timer outputsExample Timer outputs Using multiple USB-1616HS-2s per PC Detection setpoint overviewCriteria input signal is equal to Action driven by condition Setpoint configuration Using the setpoint status registerDetecting on analog input, DAC, and Firstportc updates Examples of control outputsDetection on an analog input, timer output updates Analog inputs with setpoints update on True and FalseUsing the hysteresis function Timer output update on True and FalseUsing multiple inputs to control one DAC output Detecting setpoints on a totalizing counterDetection setpoint details FIRSTPORTC, DAC, or timer update latencyControlling analog, digital, and timer outputs Firstportc Calibrating the USB-1616HS-2 Specifications Analog input specificationsAnalog input accuracy specifications AccuracyAnalog output specifications Analog outputsThermocouples Thermocouple TC types and accuracy NoteDigital input/output specifications Digital input/outputCounter specifications Input sequencer specificationsCounters Input sequencerPower consumption Frequency/pulse generator specificationsPower consumption specifications Note Frequency/pulse generatorsExternal power USB specificationsSignal I/O connectors and pin out EnvironmentalUSB-1616HS-2 screw terminal pin out single-ended connections USB-1616HS-2 screw terminal pin out differential connections Declaration of Conformity USAMailinfo@mccdaq.com