Restart Protection; Fast Mains Recovery - Lenze i55AE125B Manual

Additional functions
Mains failure control

Fast mains recovery

11.15.2

Restart protection

The integrated restart protection is to prevent a restart in the lower frequency range if the
mains voltage was only interrupted briefly (mains recovery before the motor stands still).
In the default setting 0x2D66:008 (P721.08)
•
In order to activate the restart protection, set the restart threshold in [Hz] in
•
(P721.08) below which no automatic start shall take place after mains recovery.
If, in case of mains recovery, the output frequency is below the restart threshold, the
•
restart protection gets active:
If the current DC-bus voltage is lower than the voltage setpoint
•
the motor is continued to be decelerated (until frequency 0 Hz).
If the current DC-bus voltage is higher than the voltage setpoint
•
the motor is accelerated in a controlled way until the output frequency exceeds the
restart threshold.
If, in case of mains recovery, the output frequency is above the restart threshold, the
•
motor is accelerated again to the frequency setpoint.
Diagnostic parameters:
An active restart protection is displayed via the status bit 0 in
•
mains failure control is not active.
Terminating the active restart protection
If, after mains recovery, the restart protection is active, it can be terminated by the following
actions:
Error reset via the trigger set in
•
Short-time inverter disable via the trigger set in
•
Restart via the trigger set in
•
11.15.3 Fast mains recovery
A fast mains recovery is caused by a short interruption at the energy supply company (for
instance due to a thunderstorm) and by faulty components in the supply cables (for instance
slip rings).
The fast mains recovery causes a restart of the motor
if the restart protection is deactivated
•
or
the restart protection does not get active (output frequency >
•
If this behaviour is not desired, you can decelerate the restart by setting a switch-off time in
0x2D66:007 (P721.07) or prevent it in connection with the restart protection.
tection
^ 488
488
= 0 Hz, the restart protection is deactivated.
4Fast mains recovery
0x2631:004 (P400.04).
0x2631:001
0x2631:002 (P400.02).
(0x2D66:008 (P721.08)
0x2D66:008
0x2D66:005 (P721.05),
0x2D66:005 (P721.05),
^ 488
0x2D66:009 (P721.09) if the
(P400.01).
= 0 Hz, default setting)
0x2D66:008 (P721.08)).
4Restart pro-