Spectrum Controls 1756sc-CTR8 - Manual (Page 7)

Preface
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DC - Direct Current - This is typically associated with a DC square-
wave pulse signal from a flowmeter.
dB (decibel) – A logarithmic measure of the ratio of two signal levels.
Digital filter - A low-pass mathmatic single order filter applied to the
signal. The digital filter provides high-frequency noise rejection.
Effective resolution – The number of bits in the channel data word that
do not vary due to noise.
Local System - A control system with I/O chassis within several feet of
the processor.
LSB (least significant bit) – The bit that represents the smallest value
within a string of bits.
Normal mode rejection (differential mode rejection) – A logarithmic
measure, in dB, of a device’s ability to reject noise signals between or
among circuit signal conductors, but not between the equipment grounding
conductor or signal reference structure and the signal conductors.
Module update time – See channel update time.
Remote system - A control system where the chassis can be located
several thousand feet from the processor chassis. Chassis communication
is via the 1756-DHRIO and 1756-ENET Adapter.
Resolution – The smallest detectable change in a measurement, typically
expressed in engineering units (e.g. 0.15 °C).
Sampling time - The time required by the mocule to sample an input
channel.
Step response time – The time required for the module to reach 95% of
its expected, final value, given a full-scale step change in the output data
word.
Tags - Identifiers for configuration, data, and status information found
withing the module. Tags allow the user to modify specific module
attributes and view data and status.
Update time – The time for the module to sample and convert a channel
input signal and make the resulting value available to the ControlLogix
processor.