Mitsubishi Electric 800 Series Instruction Manual page 442

 PID output hold (Pr.1361 and Pr.1362)
• The manipulated amount (PID output) can be fixed when the fluctuation of the deviation is small. This function eliminates
unnecessary acceleration/deceleration, which is effective to reduce the power consumption.
• When the deviation falls within the Pr.1362 PID output hold range and the elapsed time exceeds the Pr.1361 Detection
time for PID output hold, the manipulated amount (PID output) is fixed at the output frequency at that time.
• Even if the deviation falls out of the PID output hold range, the manipulated amount (PID output) is maintained for the
detection time for PID output hold.
Detection time for PID output hold
Output value
Set point
Measured value
Manipulated
amount
NOTE
• While the PID output is held, calculation is not performed for the P term, I term, and D term. For the P and I terms, the
values at the start of the holding period are kept. The D term is set to "0".
• When the control switches between the first PID control and second PID control, the PID output holding state is canceled.
• The PID output holding function is disabled in the following cases:
When Pr.1362="9999", while the PID setting is not applied to the frequency, during the sleep function, at switching to the
auxiliary motor in the multi-pump function, during PID gain tuning, and during the sleep boost.
 Stirring function during the PID sleep (Pr.1364 and Pr.1365)
• This function starts the pump periodically to prevent clogging of the pump while the PID output suspension function (sleep
function) is activated.
• When the sleep function is activated and the elapsed time exceeds the Pr.1365 Stirring interval time, the pump is
operated at the stirring frequency (Pr.232 or Pr.233). The pump decelerates to stop when the elapsed time exceeds the
Pr.1364 Stirring time during sleep. The interval time count for the second time onward starts after the previous
deceleration stop is completed.
Output frequency
Pr.232
(Pr.233)
PID ON
SLEEP
STIR
• The rotation direction depends on the Pr.232 and Pr.233 settings.
Stirring frequency
Pr.232 setting Pr.233 setting
9999 9999
0 to 590 Hz Arbitrary
9999 0 to 590 Hz
(Pr.1361)
Deviation
PID output is held.
Interval time Stirring time
(Pr.1365) (Pr.1364)
ON
ON
Rotation direction
― The stirring function during the PID sleep is disabled.
Command direction Pr.232 frequency is used for stirring.
Opposite to the Pr.233 frequency is used for stirring.
command direction
Detection time for PID output hold
(Pr.1361)
PID output hold range (Pr.1362)
Interval time
(Pr.1365)
Remarks
Time
Time
Stirring time
(Pr.1364)
Time
ON
5. PARAMETERS
5.11 (A) Application parameters
3
4
5
5
5
6
7
8
9
10
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