User`s manual

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MELSEC-Q
9 CONTROL OPERATION INSTRUCTIONS
(5) Deviation check
A deviation check is made under the following condition and the result of the check is output to
DVLA of the alarm detection (ALM) and the deviation large alarm (BB1) of the block memory.
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
*1: When DVLI or ERRI of the alarm detection inhibition (INH) is 1, DVLA and BB1 turn to 0 since the
alarm is inhibited.
(6) Loop stop processing
(a) Setting 1 in SPA of the alarm detection (ALM) selects a loop stop.
A loop stop performs the following processing and terminates the S.SPI instruction.
1) BW is turned to 0.
2) DVLA of the alarm detection (ALM) is turned to 0.
3) The operation mode (MODE) is changed to MAN.
4) BB1 of BB are turned to 0.
(b) Setting 0 in SPA of the alarm detection (ALM) selects a loop run.
A loop run performs "(7) Operating time/hold time check judgment ".
(7) Operating time/hold time check judgment
Whether it is the operating time (ST) or hold time (HT STHT ST) is judged and the
following processing is performed.
(a) Operating time (ST)
SV setting processing, tracking processing, gain (Kp) operation processing, PI operation
(operating time) and deviation check are performed.
(b) Hold time (HT
STHT ST)
Tracking processing, SPI operation (hold time) and deviation check are performed.
Under the following condition, however, the hold time is set to 0 and continuous PI control
is carried out.
STHT
T
ST
T
When the integer part of
STHT
T
is 0, no processing is performed. ( MV also remains
unchanged.)
Error
• When an operation error occurs Error code: 4100