Omron EJ1G User Manual page 63

Setup Procedure
42
mands for the initial channel in the group and set to STOP and AUTO
modes. Groups using 2-PID control also need to be in STOP mode.
Group
1
2
3
4
b. Read the PV for all channels in groups for which GT is to be executed
and wait for all values to stabilize.
Note Correct tuning results will not be obtained if GT is started before the
PV stabilize.
c. GT is executed by executing an operating command for the initial
channel in the group for which GT is to be executed.
Channel status bit 2 (GT Execute/Cancel) is ON during GT.
Example: Executing Gradient Tuning for Group 3
An operating command is executed for channel 9 to execute GT.
Note Execute an operating command for the initial channel in the group
to cancel GT if an error occurs during GT execution.
Note If any of the following conditions occur, GT will stop and channel
status bit 12 (GT Error) will turn ON for the initial channel in the
group. In such cases, remove the cause of the error and execute
GT again.
• If an input error has occurred.
• If the PV for the channel being output exceeds the SP.
Control may not be possible if the SP is too low, the output remains
ON, or the response speed of the control target is too fast.
During GT, the outputs in the group turn ON and OFF in order and the con-
trol target characteristics are measured. The following diagram shows the
actual operation.
Example: GT for a 3-channel Configuration
GT started
CH1 temperature
CH1 output
CH2 temperature
CH2 output
CH3 temperature
CH3 output
d. Wait until the GT Execute/Cancel bit turns OFF.
GT is completed when this bit turns OFF. Read the PID for each chan-
Channel status
Check the status of channel 1.
Check the status of channel 5.
Check the status of channel 9.
Uses 2-PID control and, therefore, does not
need to be checked.
Section 3-1
GT finished