이전 RES 명령을 설명 할때 간략하게 설명 했었습니다.
그럼 다시 한번 설명 하기로 하지요.
위 이미지는 I:1/0 비트가 ON 하면 T4:0 지정된 데이터(0.1초타이머-3초간 설정)
만큼 되면 T4:0/DN 이 ON 된다.
RTO 타이머는 적산 타이머 이다.
그래서 설정된 시간만큼 쌓이게 되면 T4:0/DN 이 ON 된다.
만일 I:1/0 비트가 T4:0 설정치에 도달 하기전에 OFF 되면 T4:0 데이터(ACC)에는
이전 데아터가 그대로 보존 되어 있다.
현재치 대이터를 RESET(초기화-ZERO) 하고 싶으시면
이전에 설명한 RES 명령어를 사용하지면 된다.
그럼 건강 조심들 하세요.
[-원본글-]
Use the RTO instruction to turn an output on or off after its timer has been on for a preset time
interval. The RTO instruction is a retentive instruction that begins to count timebase intervals when
rung conditions become TRUE.
The RTO command is very similar to the TON and TOF command except for the fact that the
Accumulated value is retained even if the rung conditions go FALSE. Like the other timers, the
Enable and Timer Timing bits work the same way, Enable is ON when the rung is TRUE and OFF
when the rung is FALSE. The Timer Timing bit is ON when the rung is true and the accumulated
value is less than the preset value and is OFF when the rung goes FALSE or when the Done bit is
set. The Done bit however is ON when the accumulated value is equal to or greater than the preset
value like the other timers, however, it can only be reset by the RES command.
This timer contains the same fields of operation as the TON and TOF command, Timer, Time Base,
Preset, and Accumulated and are used in the same way. Also, like the TON and TOF commands,
the Preset and Accumulator bits are addressable and can be changed within the program based on
certain rung conditions.
Develop a ladder rung that will cause the Retentative Timer On T4:0 to begin counting when the
input I:1/0 is TRUE. Have the counter count to 30 seconds with a Time Base of 1.0 seconds and an
Accumulator Value of 0.
In this example the input is an XIC instruction used to make the rung either TRUE or FALSE. When
this input I:1/0 is TRUE, the Enable (EN) bit is ON and the Timer Timing (TT) is ON (as long as the
accumulated value is less than the preset value). The Done (DN) bit is ON only if the accumulated
value is equal to or greater than the preset value. Note that even if rung conditions go FALSE during
the 30 second time cycle, the Accumulator bit will NOT reset, therefore, when rung conditions
become TRUE again, the Accumulator starts with the value it retained when rung conditions went
FALSE. The Done bit and/or the Accumulator bit will retain their settings whether rung conditions
are TRUE or FALSE and can ONLY be reset using the RES command.
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