Lenze i55AE155F

11.15.1 Acvang the mains failure control
1.
Set the selecon "Enabled [1]" in 0x2D66:001 (P721.01).
2.
Set the acvaon threshold in [%] with reference to the nominal DC-bus voltage in
0x2D66:002 (P721.02).
•
Recommended seng: 5 ... 10 % above the error threshold for undervoltage (display in
0x2540:003 (P208.03)).
3.
Set the voltage setpoint onto which the DC-bus voltage is to be maintained in 0x2D66:005
(P721.05).
•
Recommended seng: 95 ... 100 % (of the nominal DC-bus voltage).
The mains failure control gets acve with these sengs if the DC-bus voltage falls below the
acvaon threshold. The DC-bus voltage controller now generates the required operaonal
energy from the rotaonal energy of the motor. The motor is decelerated by the mains failure
control. Thus, the deceleraon ramp is shorter than the one of a non-guided system (coasng
drive).
Aer the mains failure control has been acvated:
1.
The DC-bus voltage is controlled with the acceleraon me set in 0x2D66:006 (P721.06) to
the setpoint set in 0x2D66:005 (P721.05).
2.
An internally generated frequency setpoint is transferred to the motor control which ena-
bles the motor (via the frequency setpoint) to be decelerated to a frequency close to
"0 Hz".
•
Starng value for the guided deceleraon is the current output frequency.
•
The deceleraon ramp (and hence the braking torque) results from the moment of
inera of the load machine(s), the power loss of the drive (system) and the set parame-
terisaon.
Behaviour aer mains recovery
If, aer mains recovery, the DC-bus voltage has exceeded the acvaon threshold (+hystere-
sis) again, an internal ming element is started. Aer the me period set in 0x2D66:007
(P721.07) has elapsed, the mains failure control is stopped if the restart protecon is not ac-
vated (default seng).
4Restart protecon ^ 488
4Fast mains recovery ^ 488
Addional funcons
Mains failure control
Acvang the mains failure control
487