Lenze 8400 - Page 190

5 Motor control (MCTRL)
5.6 V/f control (VFCplus + encoder)
190
Lenze · 8400 HighLine · Reference manual · DMS 12.0 EN · 06/2017 · TD23
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 How to adapt the slip regulator gain to the operating conditions:
1. Adapt the slip regulator gain (C00972
) to the encoder increment according to table [5-1].
2. Set controller limitation (C00971/1
) to half the slip frequency (≈ 2Hz).
3. Select speed setpoint (e.g. 20 % of the rated speed).
4. Enable inverter.
5. Increase the slip regulator gain (C00972
) until the drive is semi-stable.
• This can be recognised by motor noises or "humming" of the motor or by a noise on the
actual speed signal.
6. Reduce slip regulator gain (C00972
) until the drive runs stable again (no motor
"humming").
7. Reduce slip regulator gain (C00972
) to approx. half the value.
• With low encoder resolutions, another reduction of the slip regulator gain for low speeds
may be necessary (speed setpoint
≈ 0).
• We recommend to finally check the behaviour at setpoint speed = 0 and to further
reduce the slip regulator gain if irregular running occurs.
8. Increase controller limitation (C00971/1
) again (e.g. to twice the slip frequency).
Slip regulator time constant Ti
 How to set the slip regulator time constant:
1. Set controller limitation (C00971/1
) to half the slip frequency (≈ 2Hz).
2. Select speed setpoint (e.g. 20 % of the rated speed).
3. Enable inverter.
4. Reduce the slip regulator time constant (C00973
) until the drive is semi-stable.
• This can be recognised by motor noise, "motor vibrations" or resonance on the actual
speed value signal.
5. Increase slip regulator time constant (C00973
) until the drive runs stable again (no motor
"oscillation").
6. Increase the slip regulator time constant (C00973
) to approx. twice the value.
7. Increase controller limitation (C00971/1
) again (e.g. to twice the slip frequency).