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Rockwell Automation 1756-HSC ControlLogix High Speed Counter Module User Manual

Page 121

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Publication 1756-UM007C-EN-P - November 2011

Glossary

121

sensor A digital or analog transducer (a device such as a limit switch, push button

switch, pressure sensor, or temperature sensor) that generates an electrical
signal through an input circuit to a controller.

single-ended 1) Unbalanced, as when one side is grounded. See unbalanced circuit

(

page 121

) 2) Contrasted with differential (

page 117

).

synchronous 1) In step or in phase, as applied to two or more circuits, devices, or machines.

2) Contrasted with asynchronous (

page 115

).

tag A named area of the controller’s memory where data is stored like a variable.

For example, an I/O definition file may contain a tag

(definition) for each I/O, with

each I/O definition containing a unique

tag name by which the I/O can be

addressed.

unbalanced circuit 1) A circuit whose two sides are electrically dissimilar, as when one side is

grounded. 2) Contrasted with balanced circuit (

page 115

).