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SC100/200 Series Function Block Application Manual EM-6460-C
6.4 TIMER AND COUNTER BLOCKS
Timer and Counter are similar in functions. Timer counts internal clock pulses while Counter counts external pulse signals.
6.4.1 TIMER
Timer block has Count SW (S1), Interrupt SW (S2) and Complete status output (Y1) to control precise counting operation.
• Counting is reset and off when S1 is off.
• S2 is used to temporarily stop time counting. Counting is off when S2 is on.
• Y1 is turned on when the preset time has been elapsed (counted).
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WITHOUT COUNT INTERRUPTION
• The timer starts counting when the S1 is turned on.
• The Y1 is turned on when the preset time has been elapsed.
• When the S1 is turned off, the Y1 is also reset to off.
• The S2 always remains off.
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WITH COUNT INTERRUPTION
• Turn on the S2 to interrupt counting.
6.4.2 COUNTER
Counter block counts external pulse inputs at Pulse input SW (S2) until the count reaches a preset value and Complete
status output (Y1) is turned on. Counting is reset and off when Run SW (S1) is turned off.
• Shut off external signal inputs to the S2 to interrupt counting.
• Pulse input cycle must be longer than one computation cycle.
S1
Y1
Count SW
Complete status
S2
Interrupt SW
count
complete
S1
Y1
Count SW
Complete status
S2
Interrupt SW
count
interrupt
count
complete
S1
Y1
Run SW
Complete status
S2
Pulse input SW
count
complete
