Measurement Computing Personal Daq/3000 Series - Manual (Page 19)

Calibration
Every range of a Personal Daq/3000 Series 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. The user can adjust the calibration of the board while it is installed in the acquisition system
without destroying the factory calibration. This is accomplished by having 3 distinct calibration tables in
the on-board EPROM.
The user can select any of the three cal tables provided [factory, user, or self-cal tables] by API call or from
within software. Self-cal can be performed automatically via the included software and without the use of
external hardware or instruments. Self-cal derives its tracebility through an on-board reference which has a
stability of 0.005% per year.
Note that a 2-year calibration period is recommended for Personal Daq/3000 Series modules.
Reference Note:
Chapter 4, Calibration, discusses using a temperature calibrator with a Personal Daq/3000
Series module.
Analog Output
Personal Daq/3000 and /3001 Only
Personal Daq/3000 has two 16-bit, 1 MHz analog output channels. Personal Daq/3001 has four such
channels. Analog outputs can be updated at a maximum rate of 1 MHz.
The channels have an output range of -10V to +10V. Each D/A can continuously output a waveform. This
can be read from PC RAM or from a file on the hard disk. In addition, a program can asynchronously
output a value to any of the D/As for non-waveform applications, presuming that the D/A is not already
being used in the waveform output mode.
When used to generate waveforms, the D/As can be clocked in several different modes. Each D/A can be
separately selected to be clocked from one of the following sources.
o
Asynchronous Internal Clock. The internal programmable clock can generate updates ranging
from 1.5 Hz to 19 hours, independent of any acquisition rate.
o
Synchronous Internal Clock. The rate of analog output update can be synchronized to the
acquisition rate derived from 1 MHz to once every 19 hours.
o
Asynchronous External Clock. A user-supplied external input clock can be used to pace the
D/A, entirely independent of analog inputs.
o
Synchronous External Clock. A user-supplied external input clock can pace both the D/A and
the analog input.
Personal Daq/3000 Series User’s Manual 988093 Daq Systems and Device Overviews 1-11