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11 PROCESS CONTROL INSTRUCTIONS
11.3 Control Operation Instructions
Note that special processing is performed in the following cases.
■Deviation check (5)
A deviation is checked under the following conditions, and the result is output to the DVLA of the alarm detection (ALM) and
the large deviation alarm (BB1).
*1 If the DMLI or ERRI of the disable alarm detection (INH) is set to 1, the DVLA of the alarm detection (ALM) and the large deviation alarm
(BB1) are set to 0.
■Loop stop processing (6)
The following processing is performed according to the SPA status of the alarm detection (ALM).
■Operating time monitoring (7)
The instruction checks whether ST or HT (= STHT - ST) is applicable and performs the following processing.
Condition Processing
In any of the following cases:
1. Integral constant (I) = 0 (T
I
= 0)
2. MHA2 or MLA2 of alarm detection 2 (ALM2) is 1.
and
3. MHA2 or MLA2 of alarm detection 2 (ALM2) is 1.
and
Condition Result
DVL < |DV| DVLA = BB1 = 1
*1
(DVL - DVLS) < |DV| DVL DVLA = BB1 = Last value status hold
*1
|DV| (DVL - DVLS) DVLA = BB1 = 0
SPA status Processing details
1 The loop stops. When the loop stops, the following operations are performed and the S.SPI instruction ends.
• The output value (BW) is set to 0.
• The DVLA of alarm detection (ALM) is set to 0.
• The control mode (MODE) is set to MAN.
• BB1 of BB is set to 0.
0 The loop runs and "operating time/hold time determination (7)" is performed.
Condition Processing details
Operating time (ST) The instruction performs the following processing steps: SV setting, tracking, gain (Kp) operation, PI operation
(operating time), and deviation check.
Hold time (HT) (= STHT - ST) The instruction performs the following processing steps: tracking, SPI operation (hold time), and deviation
check.
Under the following conditions, however, PI control is performed continuously with the hold time set to 0.
If the integral part of the left side of the above expression is 0, no processing is performed. (BW also remains
unchanged.)
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