Rockwell Automation 1769-OF4 Compact Analog Output Module User Manual
Page 69
Publication 1769-UM020A-EN-P - December 2009
69
Glossary
overall accuracy – The worst-case deviation of the output voltage or
current from the ideal over the full output range is the overall
accuracy.
Gain error, offset error, and linearity error all contribute to output
channel accuracy.
output accuracy – The difference between the actual analog output
value and what is expected, when a given digital code is applied to
the d/a converter. Expressed as a ± percent of full scale. The error
will include gain, offset and drift elements, and is defined at
25 °C (77 °F), and also over the full operating temperature range,
0…60 °C (0…140 °F).
output image – The output from the controller to the module
outputs. The output image contains the digital output data to be
converted to analog output signals by the module.
repeatability – The closeness of agreement among repeated
measurements of the same variable under the same conditions.
resolution – The smallest detectable change in a measurement,
typically expressed in engineering units (for example, 1 mV) or as a
number of bits. For example a 12-bit system has 4096 possible output
states. It can therefore measure 1 part in 4096.
status word – Contains status information about the channel’s current
configuration and operational state. You can use this information in
your ladder program to determine whether the channel data word is
valid.
update time – See