Measurement Computing Personal Daq rev.6.0 - Manual (Page 105)

Calibration 6
Introduction ……6-1
Required Equipment ……6-2
Calibration Procedure ……6-2
Introduction
Although Personal Daq units are calibrated prior to shipment, they still require periodic calibration to
ensure that accuracy is maintained. The industry standard for this calibration is once per year.
UserCal provides prompts to assist you through Personal Daq’s calibration procedure. The Windows-
based program was developed with the intent of making the calibration task easy to perform.
Note: Calibration constants are calculated and stored in each Personal Daq unit’s serial EEPROM. This
permits adding expansion modules to single Personal Daq units. It also allows you to swap
expansion modules from one Personal Daq unit to another.
CAUTION
Use approved ESD precautions, including static-free work area and grounded wrist strap,
when handling electronic components. Failure to do so could cause equipment damage
due to electrostatic discharge.
Calibration is to be performed by authorized personnel in a controlled, still air
environment at 23±2°C. Failure to comply with this requirement can result in faulty
equipment performance and necessitate additional services of an authorized metrology lab.
The VDC Calibrator used must meet the following criteria:
1) Range: 0 - 10 V
2) Resolution: 10 µV
3) Peak-to-peak noise: 600 µV
The digital voltmeter (or digital multimeter) used to verify calibration voltage accuracy
must meet the following criteria:
1) Minimum Resolution: 6-1/2 digits
2) Minimum DC Accuracy: 0.005% full scale
Failure to comply with these requirements can result in faulty equipment performance
and necessitate additional services of an authorized metrology lab.
Never connect an expansion module to (or remove it from) a Personal Daq main unit while
the main unit is connected to a power source. Such action may result in EEPROM errors
and loss of calibration data.
Allow at least 1 hour warm-up time for the VDC Calibrator, Digital Multimeter, and each
Personal Daq unit (including expansion module) that is to be calibrated. If a cold cell
device is used, allow the cell to warm up in accordance with device operator’s manual.
Personal Daq User’s Manual 878395 Calibration 6-1