KEB COMBIVERT F5 MULTI Applications Manual page 255

Special Functions
Restart at minimum Output
(Pn.44 Bit 3, 4)
Restart delay (Pn.52)
Examples
Funcion description F5-G
Power loss ride-through
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Afterwards it is accelerated to the current setpoint value. Below the restart value
it is delayed in case of power recovery with the fast-stop-function (DEC ramp at
F5-B/C).
2. Regulation onto the voltage setpoint, it the output value is smaller than the restart
value (Pn.44 Bit 6+7 = 2):
As long as the oputput frequency and/or the actual speed is larger than the
restart value, the inverter behaves as described under Point 1. Below the restart
value the voltage setpoint value of Pn.50 is increased and with active current
control (without speed detection) the control parameters of the active current
control are reduced linearly with the output value.
3. Regulation onto the voltage setpoint Pn.50 or braking torque Pn.47 (Pn.44 Bit 6+7 =
1 or 3):
The control parameters of the active current control (without speed detection)
are reduced below the restart value linearly with the output value.
Bit 3 and 4 of Pn.44 determine the behaviour of the drive upon attaining the minimum
value
output value.
• Bit 3 = „0" and Bit 4 = „0"; the inverter modulates independent of a set direction
of rotation with the adjusted boost and is in status „POFF" (Caution: Motor
heating). A reset is necessary for the restart.
• Bit 3 = „1" and Bit 4 = „0"; the inverter modulates independent of a set direction
of rotation with the adjusted boost and is in status „POFF". After expiration of
the restart delay Pn.52 (if adjusted) the inverter restarts automatically.
• Bit 3 = „0" and Bit 4 = „1"; the inverter switches off the modulation and is in
status „PLS". A reset is necessary for the restart.
The restart delay is the time during which the output value is kept constant after power
recovery, if a restart is allowed. It is adjustable within the range of 0...100 s (Default
0 s). After expiration of the time it is accelerated again onto the current setpoint value.
To better understand the correlation, the operating modes are explained according to
the control types in the following section.
If the Power-Off-function is switched on (Pn.44 Bit 0 =1), it becomes active if the DC-
link voltage drops below the starting voltage value. In the first cycle the frequency jump
is given which shall put the drive into no-load running. Afterwards it is regulated onto
the DC-link voltage or only onto the active current respectively slip depending on the
setpoint value source. The changeover between active current control (without speed
detection) and slip control (with speed detection) takes place over cs.1. At cs.1 = 2
(actual value = calculated value) the active current control is active, at cs.1 = 0 or 1
the slip control is active.
Set value source
Starting voltage (Pn.44 Bit 6-7 = Mode 0) or setpoint DC-link voltage Pn.50, if output
value < restart value Pn.48 (Pn.44 Bit 6-7 = Mode 2)
In this mode the motor shall be operated almost in no-load operation and shall feed
Name: Basis
KEB COMBIVERT F5
Functional Description
Date
04.05.04
Chapter Section Page
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