Measurement Computing DAC488 v.1 - Manual (Page 56)

50 DAC488 Calibration DAC488 User’s Manual
After the last port is tested, a summary report will be printed similar to that below:
Calibration Report
Manufacturer: Model: DAC488/4 Serial#
Port Range %Err +FS %Err -FS Offset Err J Vals H Val
1 1 +0.003 -0.003 +28.000E-06 136 146 +15 Passed
1 2 -0.002 +0.000 -20.000E-06 118 126 +17 Passed
1 3 +0.001 -0.001 +0.000E+00 116 123 +18 Passed
2 1 -0.004 +0.003 -37.000E-06 112 98 -1 Passed
2 2 -0.001 +0.000 +0.000E+00 120 104 +3 Passed
2 3 -0.002 -0.001 -20.000E-06 119 102 +5 Passed
3 1 -0.001 +0.001 -27.000E-06 115 111 +11 Passed
3 2 -0.003 +0.001 -20.000E-06 118 113 +8 Passed
3 3 -0.001 +0.001 +0.000E+00 112 106 +1 Passed
4 1 +0.003 -0.007 +41.000E-06 123 113 +8 Passed
4 2 -0.002 +0.003 -50.000E-06 122 111 +18 Passed
4 3 +0.001 -0.001 -10.000E-06 127 114 +30 Passed
Automatic Calibration Summary Report
A description of each item in the auto-calibration summary report is given below:
•
Port: This column shows which of the four ports is being tested.
•
Range: This column shows which of the three volt ranges is being used, where 1 represents the
±
1 volt
range, 2 represents the
±
5 volt range, and 3 represents the
±
10 volt range.
•
%Err +FS: This is the percent of Error at positive Full Scale (FS) Reading. This is computed using
the following formula:
(FS Reading - FS Voltage)/(FS Voltage) x 100% = %Err +FS
For example, if a DAC port is programmed for 10 volts on the 10 volt scale and the voltmeter reading
10.0001 volts, then the percent of Error would be:
(10.0001 - 10.0000)/(10.0000) x 100% = +0.001%
•
%Err - FS: This is the percent of Error at negative Full Scale (FS) Reading. This is computed using
the following formula:
(FS Reading - FS Voltage)/(FS Voltage) x 100% = %Err -FS
For example, if a DAC port is programmed for -5 volts on the 5 volt scale and the voltmeter reading -
5.0002 volts, then the percent of Error would be:
(-5.0002 - -5.0000 )/( -5.0000 ) x 100% = -0.004%
•
Offset Err: This column shows the measured output voltage when the port is programmed to output 0
volts.
•
J Vals: These two columns show the positive and negative Gain Calibration Constants for each port
and range. The positive Gain Calibration Constant is printed first.
•
H Val: This column shows the Offset Calibration Constant for each range and port.