Mitsubishi Electronics 700 Series, FR-A700 specifications Timer timing method

Description of devices

(2)Present value update timing and accuracy in refresh system

1)The timer accuracy is +2 scan times independently of the used timer and scan time.

2)The following shows the present value update timing and accuracy when the 10ms timer is used in a program where the scan time is 10ms or more.

Ladder example

T3 contact turns on 6s after X0 turns on. (T3 is 10ms timer.)

Timer timing method

Scan time 25ms

END		OUT		OUT			OUT		END			OUT		END
When external		T3		END T3		END T3					END T3
		25ms			25ms			25ms					25ms
input turns on				ON
in hatched
range	OFF
X0					ON
T3 coil	OFF
															ON
T3 contact	OFF
10ms timer		1	2	1	2	3		1	2	1	2	1		2	3
timing
Timing set				2			3			2		2			3
at END
T3 present						0	3	3	3	2	5	597	2	599	599	3	602
													*1
value
												1 scan
		*2							6000ms			0
		1 scan
		0

600 appears when monitored on peripheral device.

Fig 3.17 Timer Timing Method

In Fig. 3.8, the time-out period of the 10ms timer T3 has the following errors. *1 .......... 10ms timer error (+1 scan time)

*2 .......... Error produced by timer's input condition ON timing and OUT

T instruction's program position (+1 scan time) The accuracy is +2 scan time (+0.05s in Fig. 3.8)

3)When the timer times out, its contact remains on until END even if the coil turns off, and turns off at execution of the END instruction.

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