STEP ET Series - Page 131

Chapter 7 Parameter Explanation
ET/EP/EH Series Intelligent Flexible Driver Manual
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In a closed loop system with feedback, the main and auxiliary feedback can be analog or pulse.
The process closed loop feedback main and auxiliary operation function is the same as that of the
process closed loop reference and the process open loop reference. See P50.01 for details.
P51.04 closed loop control main feedback mode is selected as follows.
0: None; 1: A0; 2: A1; 6: Modbus communication reference
P51.05 closed loop control auxiliary feedback mode is selected as follows.
0: None; 1: A0; 2: A1; 6: Modbus communication reference
P51.06 closed loop control feedback main and auxiliary operations are selected as follows.
0: No operation; 1: Main ＋ auxiliary; 2: Main - auxiliary; 5: Taking maximum value; 6: Taking
minimum value
Note: The closed loop control analogs such as main reference, auxiliary reference, main feedback
and auxiliary feedback cannot be set to the same channel.
Function code
Name
Setting range
Factory setting
P51.07
PID internal setting value
0.00~10.00
0.70
The current control operation mode P51.00=1 should be determined before determining the process
closed loop reference.
When the current control operation mode is analog feedback process closed loop, if P50.01 is set to
0, P51.07 is used to determine the closed loop reference value.
Function code
Name
Setting range
Factory setting
P51.09
Proportional gain Kp
0.000~10.000
0.500
P51.10
Integral gain Ki
0.000~10.000
0.500
P51.11
Differential gain Kd
0.000~10.000
0.000
The larger Kp is, the faster the response is, but it is easy to oscillate if it is too large. Kp can’t
completely eliminate deviation, but Ki can be used to eliminate deviation. The larger Ki is, the faster
the inverter responds to the variation of deviation, but it is easy to cause oscillation if it is too large.
If there is jumping feedback in the system from time to time, it is necessary to use Kd, which can
quickly respond to deviation changes between the system feedback and the set value. A greater Kd
value gives rise to quicker response, but an excessively large value may cause oscillation.
Function code
Name
Setting range
Factory setting
P51.12
Integral option method
0~1
0
This function determines the specific mode of running during the process closed loop regulation.
If the output of the process closed loop regulation reaches the upper or lower frequency limit
(P70.00 or P70.01), there are two action options in the integration.
0:When the frequency reaches the upper and lower limits, the integration regulation is stopped
The integral value remains the same, and when the size between the set value and the feedback value
changes, the integral value will quickly follow this trend.
1: When the frequency reaches the upper and lower limits, the integral control continues.
The integral value responds to the change between the set value and the feedback value in real time,
unless the internal integration limit has been reached. When the size between the set value and the
feedback value changes, it will take longer to counteract the influence of continuous integration
before the integral value follows this trend.