21 DEVICES
21.3 User Device
341
21
Accuracy of timers
This sections describes the accuracy of timers.
■
Timer (T/ST)
The scan time value measured by the END instruction is added to the current value when the OUT T
instruction is executed.
If the timer coil is turned off when the OUT T
instruction is executed, the current value is not updated. The maximum
response accuracy of the timer (the time duration from capture of an input (X) to output of it) is "2 scan time + timer time limit
setting".
Ex.
Timer limit setting = 10ms, setting value of T0 = 8 (10ms
8 = 80ms), scan time = 25ms
(1) Accuracy from when the coil of the timer turns on until when the contact of the timer turns on
- (1 scan time + timer limit setting) to (1 scan time)
(2) Timing on when the coil of the timer turns on
(3) Input fetching timing
X0
T0
K8
2
1
1
1
2
1
1
2
2
1
2
ON
OFF
OFF
OFF
ON
ON
OFF
ON
3
2
3
3
2
3
2
3
2
3
25ms
25ms
25ms
25ms
25ms
25ms
0+2=2
2+3=5
5+2=7
7+3=
(1)
(2)
(3)
Program
External input of X0
X0 of the CPU
module
Coil of T0
Contact of T0
Scan time
Measurement at
10ms interval
Count by the END
instruction
Current value of T0
END
processing
END
processing
END
processing
END
processing
END
processing
END
processing
Содержание MELSEC iQ-R-R00CPU
Страница 2: ......
Страница 151: ...9 MONITOR FUNCTION 9 1 Real Time Monitor Function 149 9 MEMO ...
Страница 323: ...18 SEQUENCE SCAN SYNCHRONIZATION SAMPLING FUNCTION 321 18 MEMO ...
Страница 330: ...328 20 ROUTING SETTING 20 3 Precautions MEMO ...
Страница 423: ...26 BASIC CONCEPT 26 8 State Transition of the Redundant System 421 26 MEMO ...
Страница 524: ...522 30 MAINTENANCE AND INSPECTION FOR A REDUNDANT SYSTEM 30 1 Module Replacement in the Redundant System MEMO ...
Страница 1009: ...APPX Appendix 14 List of Available SQL Commands for CPU Module Database Access Function 1007 A MEMO ...
Страница 1014: ...1012 APPX Appendix 15 Added and Enhanced Functions MEMO ...
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