Mitsubishi Q Series User Manual page 41

3 SPECIFICATIONS
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2) The PID control forced stop command (YnC, YnD) has been turned
ON.
3) The mode switching is changed to other than the standard control
mode. (Setting mode, manual control mode1 2, program control
mode, for instance.) (Except for the case where the PID continue flag
(buffer memory address:169) changed to setting mode by
"Continue.")
4) Hardware failure has occurred.
5) The measured value has exceeded the input range.
6) The following time exceeds 2 hours.
• Time elapsed from the auto tuning start until the set value is
reached at the first time.
• A half of the hunting cycle
7) The value calculated by PID constants after auto tuning exceeds any
of the following ranges.
Proportional band (P): 0.1 to full-scale ( )
Integral time (I): 0.0 to 3276.7 (s)
Derivative time (D): 0.0 to 3276.7 (s)
(3) Operation at termination of auto tuning
(a) Operation at normal termination
• The auto tuning status flag (Xn4, Xn5) turns off.
• The PID constants are set.
• The loop disconnection detection judgment time (buffer memory address:
59, 91) is set. (If the loop disconnection detection judgment time is 0 at the
start of auto tuning, it remains unchanged from 0.)
(b) Operation at abnormal termination
• The auto tuning status flag (Xn4, Xn5) turns off.
• The PID constants and loop disconnection judgement time are not set.
• The error code and the factor code of the corresponding cause are stored
into the error code (buffer memory address: 0), and ERR. LED flashes.
(Except when turned on the forced PID control stop command (YnC, YnD)
and changed to setting mode.)
For error code and factor code, refer to Section 8.1.
(4) Adjustment after auto tuning
(a) Specific readjustment is not needed for the PID constants calculated by
auto tuning.
(b) Use the control response parameters (buffer memory address: 49, 81) to
change the control response for the PID constants calculated by auto
tuning.
0.1 to 1000.0 (%)
MELSEC-Q
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