Omron EJ1G, User Manual

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76
Setting Control Specifications
Section 5-3
Note Set the limits so that the MV Upper Limit > MV Lower Limit.
If the MV Lower Limit > MV Upper Limit, the larger value will function as the
MV Upper Limit.
5-3-6 Tuning
Gradient Tuning (GT)
Gradient temperature control finds the relationship between points with
mutual interference and performs control. Gradient tuning (GT) is a series of
operations that automatically measure the degree of mutual interference and
executes PID tuning at the same time, to adjust the internal parameters that
are used to find this relationship.
Always execute GT only when all groups (including 2-PID control groups) are
stopped.
• GT cannot be executed in RUN or MANUAL modes.
• An operation command is used to execute and cancel GT. Refer to 6-4-11
Operation Commands for details.
• GT automatically calculates the differences in characteristics of the differ-
ent control objects for each channel and finds the relationship between
these differences. As a result, the differences in characteristics for each
channel does not appear as differences in PID values. The PID values
calculated using GT will be the same for all channels in the group.
• GT will stop under the following conditions.
• If an input error has occurred.
• If the PV for the channel with outputs ON exceeds the SP.
• If an operation command is executed for STOP or MANUAL modes or
to cancel GT.
• If the Operation During Error (Selection A/C/D) parameter is set to MV
at PV Error or the conditions for stopping control have been occurred
• If an internal communications error has occurred
• If the internal parameters cannot be calculated correctly from the GT
measurement results
• The following parameters are usually used at the default settings.
Note (1) This parameter can be set only while operation is stopped.
(2) The decimal point position is determined by the setting for the Decimal
Point Position B parameter. If, however, the Decimal Point Position B pa-
rameter is set to 0 (****), it will be treated as being set to 1 (***.*).
Variable type Parameter name Setting range Default
D5/95 MV Upper Limit (Channel)
−
5.0 to 105.0% 105.0
MV Lower Limit (Channel)
−
5.0 to 105.0%
−
5.0
Conditions for use No special conditions.
Variable type Parameter name Setting range Default
E5/A5 GT Natural Cooling Time
(Common) 0 to 9999 s 300
GT Stabilization Band
(Common) 0.0 to 999.9 EU (See note 2.) 1.0
Conditions for use Gradient temperature control