Whatever count was contained in the counter at the time of aprocessor shutdown will be restored to the counter on power-up.The counter can be reset on power-up if the reset conditionis activated at the time of power restoration.PLC counters can be designed to count up to a presetvalue or to count down to a preset value. Counter Counting SequenceNorthampton Community College 5PLC counters are normally retentive. They are dependent onexternal sources such as parts traveling past a sensor oractuating a limit switch for counting.CounterApplicationsRotary EncoderRotaryEncoder 5. Electronic CountersNorthampton Community College 4Electronic counters can count up, count down, or becombined to count up and down. Resettingthe counter to zero is usuallydone with a pushbutton locatedon the unit. The actuatinglever then returns automaticallyto its original position.
Mechanical CountersNorthampton Community College 3Programmed counters can servethe same functions asmechanical counters.Every time the actuating lever ismoved or rotated, the counteradds one number. CountersNorthampton Community College 2Common applications of counters include keeping track ofthe number of items moving past a given point, ordetermining the number of times a given action occurs.A preset counter can control anexternal circuit when its countedtotal matches the user-enteredpreset limits.
Allen Bradley CountersCountersChapter 05Northampton Community College 1Ģ.
0 kommentar(er)
