Omega OMB-DAQSCAN-2000 Series Manuale Utente

Daqscan/2000 Series                    

948695 

 

Calibration    9-1 

Daqscan/2000 Series devices are digitally calibrated at the factory.  The digital method 

involves storing a correction factor on the circuit board for each range at the time of 

calibration. Whenever a particular range is selected, the appropriate calibration constant is 

automatically applied to a compensating DAC, thereby calibrating the specific range. The 

result is that readings generated by the A/D are already calibrated, and do not require 

additional processing.  

This is significantly better than the calibration method in which readings are adjusted in 

software after they are transferred to the host PC.  That method reduces the dynamic range of 

the A/D, and can adversely affect the speed at which the PC obtains a calibrated reading.  

Daqscan/2000 Series devices include a user-cal mode, whereby the user can adjust the 

calibration of the unit’s board, without destroying the supplied factory calibration. This is 

accomplished with two distinct calibration tables in the unit’s on-board EPROM, one which 

contains the factory calibration factors, and the other which is available for user calibration. 

 

When calibration adjustments are needed they should be completed in the following order: 

1. 
2. 
3. 
4. 
5. 
6. 
7. 
8. 

PGA Input and Output Offset 
Sample/Hold Offset 
A/D Offset and Gain 
VDC Voltage Reference

 

DAC0 Full-Scale

1 

DAC1 Full-Scale

1

 

DAC2 Full-Scale

1

 

DAC3 Full-Scale

1

 

1

DAC Full-Scale only applies to Daqscan/2001 and DaqScan/2004. 

 

A Windows-based program, DaqCal.exe, is used to calibrate Daq systems, including analog 

expansion cards.  DaqCal.exe is used in conjunction with: 

•  a 4.5 digit, digital multi-meter 

•  an adjustable voltage calibrator 

•  an ambient temperature meter 

 

To use the calibration program: 

1.  Launch DaqCal.  

Note:   DaqCal is installed automatically from your data acquisition CD as a part 

of product support.  This takes place during software installation.  DaqCal’s 

default location is the Omega DaqX Software folder, in the Programs 

group. 

2.  When DaqCal opens you will be prompted to select your device from a list.  After 

doing so, simply follow the illustrated on-screen instructions.