Lenze 8400 - Reset Mains Failure Control

17 Function library
17.1 Function blocks | L_MFail_1
1415
Lenze · 8400 HighLine · Reference manual · DMS 12.0 EN · 06/2017 · TD23
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17.1.102.7 Reset mains failure control
The mains failure control is rest by setting bReset to TRUE.
•A reset via bReset is always required when the restart protection is active or the restart
protection is used and the supply (mains or DC supply) has been switched on.
•The bReset input can, for instance, be connected to a digital input.
17.1.102.8 Restart protection
The integrated restart protection is to prevent a restart in the lower speed range when the supply
voltage was only interrupted briefly (mains recovery before drive stands still).
•The nThreshold_a input serves to specify the restart threshold in [%] with regard to the
reference speed (C00011
) below which no start has to take place after mains recovery.
• If in case of mains recovery the speed is below the restart threshold, the drive is continued to
be braked in a controlled way. This function is only stopped by setting bReset to TRUE.
• If the speed is above the restart threshold after mains recovery, the drive changes to its
setpoint nNSet_a.
• The function is switched inactive when nThreshold_a = 0 %.
• A reset takes place by setting bReset to TRUE and is required after every mains switching.
• In this case, the bActive output is set to TRUE when the bFault input is set to FALSE.
17.1.102.9 Quick mains recovery (KU)
The quick mains recovery causes a restart of the inverter if the restart protection is not active
anymore.
• In case, the drive reaches its setpoint.
• If this behaviour is not desired, you can delay the restart by setting a retrigger time in C01470/3
or prevent it by using the restart protection.
• Dependent on the system, the mains recovery is reported through the mains failure control via
the level of the DC-bus voltage. Procedure of the mains failure control
( 1407)
A quick mains recovery is caused by a "quick interruption" of the energy supply company (e.g.
thunderstorm) and by faulty components in the supply cables (e.g. collector rings).
• Then, set the retrigger time in C01470/3
higher than the measured deceleration time reached
in braking operation.