Mitsubishi MELSEC-Q series Programming Manual page 252

S. AT1
(6) After maximum slope time-out judgment processing
Whether the auto tuning processing has reached the AT1 after maximum slope time-out time (AT1TOUT2) or not is
judged.
However, if the after maximum slope time-out time counter initial preset flag is 0, the processing in (c) is performed.
(a) If the AT1 after maximum slope time-out time (AT1TOUT2) is reached, "(10) Identification processing" is performed.
(b) If the AT1 after maximum slope time-out time (AT1TOUT2) is not reached, "(7) Stepped manipulated value set
processing" is performed.
(c) If the after maximum slope time-out time counter initial preset flag is 0, "(7) Stepped manipulated value set
processing" is performed.
(7) Stepped manipulated value set processing
Whether the stepped manipulated value is "set (1)" or "not set (0)" is judged from the stepped manipulated value preset
flag.
(a) If the stepped manipulated value preset flag is 0, the following processing is performed and the S. AT1 is
terminated.
1) The AT1 stepped manipulated value (AT1STEPMV) is added to the manipulated value (MV).
T1 = MV + AT1STEPMV
In the upper/lower limiter, the following operation is performed and the result of the operation is output to BB4
and BB5.
Condition
BB4
T1 > MH 1
T1 < ML 0
ML  T1  MH
0
2) The stepped manipulated value preset flag is turned to 1.
3) The counter from auto tuning start is cleared to 0.
4) The input value (E1) is stored into the auto tuning start-time PV0.
5) The input value (E1) is stored into the last process value (PV
6) The maximum slope value, maximum slope-time counter, maximum slope-time PV, response speed (R) and
equivalent dead time (L) are cleared to 0.
(b) If the stepped manipulated value preset flag is 1 "(8) Sampling cycle judgement processing" is performed.
(8) Sampling cycle judgment processing
Whether the sampling cycle is reached or not is judged from the AT1 sampling cycle (AT1ST).
(a) If the sampling cycle is not reached, the S. AT1 instruction is terminated.
(b) If the sampling cycle is reached, "(9) Response waveform observation processing" is performed.
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Result
BB5 BB16 MV
Original MV
0 1
unchanged
Original MV
1 1
unchanged
0 0 T1
Processing after upper/lower
limiter
S. AT1 instruction is terminated.
The processing in 2) and later is
performed.
).
n-1