Instruction manual

6. COMMUNICATION DATA
IMS01J04-E2
19
Continued from the previous page.
Name
Attri-
bute
Struc-
ture
Data range
Factory
set value
Integral time 
[H-TIO-, H-CIO-A,
H-SIO-A]
R/W C 1 to 3600 seconds
H-TIO-,
H-CIO-A:
240
H-SIO-A:
2
Derivative time 
[H-TIO-, H-CIO-A,
H-SIO-A]
R/W C 0 to 3600 seconds (0: PI action)
H-TIO-,
H-CIO-A:
60
H-SIO-A:
0
PID/AT transfer *
[H-TIO-, H-CIO-A,
H-SIO-A]
R/W C
0: PID control operation
1: AT (Autotuning) operation
The autotuning (AT) function starts its
execution with PID/AT transfer and the
request command set to “1: AT operation”
and “1: Setting,” respectively. After the
autotuning function finishes its execution,
PID/AT transfer returns to “0: PID control
operation.”
0
* Autotuning (AT) is the function which automatically measures, calculates and sets the optimum PID
constants according to the set temperature.
Caution for using the Autotuning (AT)
When a temperature change (UP and/or Down) is 1C or less per minute during
Autotuning, Autotuning may be cancelled before calculating PID values. In that case,
adjust the PID values manually. It is possible to happen when the set value is around
the ambient temperature or is close to the maximum temperature achieved by the load.
The following is the conditions necessary to carry out autotuning and the conditions which will cause
the autotuning to stop.
Conditions necessary for autotuning:
The autotuning should be executed after satisfying all of the following conditions:
 Operation mode conditions:
 Auto/Manual transfer  Auto mode
 PID/AT transfer  PID control mode
 Control RUN/STOP transfer  Control RUN mode
 The measured value (PV) is without input error range [Input error determination point (high) 
Measured value (PV)  Input error determination point (low)].
 The output limiter high limit should be more than 0.1 % and the output limiter low limit should be
less than 99.9 %.
 When operation mode is set to “Normal (Can be controlled ).”
When the autotuning is finished, the display of each channel automatically returns to “0: PID control
operation.”
Continued on the next page.