Rockwell Automation 1746-NR8 SLC 500 RTD/Resistance Input Module User Manual - Manual (Page 109)

1 Publication 1746-UM003A-EN-P
Glossary
The following terms and abbreviations are specific to this product. For a
complete listing of Allen-Bradley terminology, refer to the Allen-Bradley
Industrial Automation Glossary, Publication Number AG-7.1.
A/D A/D A/D A/D - Refers to the analog-to-digital converter inherent to the RTD/
Resistance input module. The converter produces a digital value whose
magnitude is proportional to the instantaneous magnitude of an analog input
signal.
attenuation attenuation attenuation attenuation - The reduction in the magnitude of a signal as it passes through a
system.
channel channel channel channel - Refers to one of four small-signal analog input interfaces available on
the module’s terminal block. Each channel is configured for connection to an
RTD or potentiometer input device and has its own diagnostic status word.
chassis chassis chassis chassis - A hardware assembly that houses devices such as I/O modules,
adapter modules, processor modules, and power supplies.
common mode rejection ratio common mode rejection ratio common mode rejection ratio common mode rejection ratio - The ratio of a device’s differential voltage
gain to common mode voltage gain, expressed in dB.
CMRR CMRR CMRR CMRR = 20 Log
10 (V1/V2)
common mode voltage common mode voltage common mode voltage common mode voltage - A voltage signal induced in conductors with respect
to ground (0 potential).
configuration word configuration word configuration word configuration word - Contains the channel configuration information needed
by the module to configure and operate each channel. Information is written
to the configuration word through the logic supplied in your ladder program.
cut-off frequency cut-off frequency cut-off frequency cut-off frequency - The frequency at which the input signal is attenuated 3dB
by the digital filter. Frequency components of the input signal below the
cut-off frequency are passed with under 3dB of attenuation.
data word data word data word data word - A 16-bit integer that represents the value of the analog 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) dB (decibel) dB (decibel) dB (decibel) - A logarithmic measure of the ratio of two signal levels.
digital filter digital filter digital filter digital filter - A low-pass noise filter incorporated into the A/D converter. In
addition, the digital filter provides high-rejection notches at frequencies that
are integral multiples of the filter cut-off frequency. The notches are used for
rejecting AC power line noise and higher frequency noise.