Commissioning – Lenze 8200 series User Manual

Page 44

Advertising
background image

Commissioning

5-12

UOMu_^MVMO

3.Set the Vmin boost

(C016).

Load-dependentboost of the motor voltage in the field-frequency range below the

V/f-rated frequency. C016 acts as gain factor of the auto-boost function.
Adjustment
In general, an adjustment is not necessary. An optimisation can be advantageous:
For drives with very high starting torques:
A Operate the motor under load.
B Select the frequency setpoint.
C Increase V

min

until the required motor current (torque) occurs.

Too high settings of V

min

can lead to a positive-feedback effect which activates the

TRIP ”Overcurrent” (OCx).

For drives with square load torques (fans, pumps):
A Operate the motor under load.
B Select the frequency setpoint.
C Adapt V

min

until the motor is running steadily and smoothly over the whole fre-

quency range.

Too high settings of V

min

can activate the TRIP ”Overcurrent” (OCx) and lead to an

extensive motor temperature.

For drives with special motors:
A Operate the motor under load.
B Select the frequency setpoint.
C Increase V

min

until the required motor current (torque) occurs.

Too high settings of V

min

can lead to a positive-feedback effect which activates the

TRIP ”Overcurrent” (OCx).

D Check the current consumption during idle-running when no load is applied

4.Set slip compensation

(C021)

Rough setting by means of the motor data:

Set s p co pe sat o

(C021).

л =

е

клуе

− е

к

е

клуе

⋅ NMMB

е

клуе

=

С

Зк

⋅ SM

é

s

Slip constant (C021)

n

rsyn

synchronous motor speed [min

-1

]

n

r

rated speed to motor nameplate [min

-1

]

f

dr

rated frequency to motor nameplate [Hz]

p

Number of pole pairs

Precise setting:
Change C021 under constant load until the speed is near the synchronous speed.
If C021 is set to too high values, the drive may become instable (overcompensation).

Show/Hide Bookmarks

Advertising