Allen-Bradley Compact 1769-IR6, User Manual

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Publication 1769-UM005A-EN-P
G-2
data word – A 16-bit integer that represents the value of the input
channel. The channel data word is valid only when the channel is
enabled and there are no channel errors. When the channel is disabled
the channel data word is cleared (0).
dB – (decibel) A logarithmic measure of the ratio of two signal levels.
digital filter – A low-pass filter incorporated into the A/D converter. The
digital filter provides very steep roll-off above it’s cut-off frequency, which
provides high frequency noise rejection.
effective resolution – The number of bits in a channel configuration
word that do not vary due to noise.
excitation current – A user-selectable current that the module sends
through the input device to produce an analog signal that the module can
process and convert to temperature (RTD) or resistance in ohms
(resistance device).
filter – A device that passes a signal or range of signals and eliminates all
others.
filter frequency – The user-selectable frequency for a digital filter.
full-scale – The magnitude of input over which normal operation is
permitted.
full-scale range – The difference between the maximum and minimum
specified analog input values for a device.
gain drift – Change in full-scale transition voltage measured over the
operating temperature range of the module.
input data scaling – Data scaling that depends on the data format
selected for a channel configuration word. Scaling is selected to fit the
temperature or voltage resolution for your application.
input image – The input from the module to the controller. The input
image contains the module data words and status bits.