Imax controller
For a quick commissioning, the calculations and settings are made automatically during the motor calibration.
For typical applications, a manual adaptation of the parameters of the Imax controller is not recommended. A wrong setting may have a negative effect on the control. For special applications, contact the manufacturer before adapting the parameters.
Preconditions
The Imax controller is only effective in the following motor control types:
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V/f characteristic control (VFC open loop)
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V/f characteristic control (VFC closed loop)
Details
The Imax controller becomes active in the V/f operation if the actual motor current exceeds the maximum current "Max. current". The Imax controller changes the output frequency to counteract the exceedance.
The maximum current "Max. current" is defined in 0x6073 (P324.00) in percent with regard to the rated motor current "Rated motor current" 0x6075 (P323.00).
If the maximum current is exceeded:
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During operation in motor mode, the Imax controller reduces the output frequency.
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During operation in generator mode, the Imax controller increases the output frequency.
Setting notes
If oscillations occur at the current limit during operation:
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Reduce gain of the Imax controller in 0x2B08:001 (P333.01).
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Increase reset time of the Imax controller in 0x2B08:002 (P333.02).
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Carry out the changes in small steps only (by 2 ... 3 % of the set value) until the oscillations do not exist anymore.
If the Imax controller does not respond fast enough after the maximum current has been exceeded:
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Increase gain of the Imax controller in 0x2B08:001 (P333.01).
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Reduce reset time of the Imax controller in 0x2B08:002 (P333.02).
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Carry out the changes in small steps only (by 2 ... 3 % of the set value in each case) until the response time is acceptable.
Parameter