KEB COMBIVERT F4-C Applications Manual page 175

Special Functions
Fig. 6.9.3.e Behaviour at Voltage Recovery
Pn.19 Restart frequency when
Pn.17 and Pn.42 = 199 (auto-
matic)
0...409,5 Hz
Behaviour at Voltage Recovery
Restart Frequency
(Pn.19)
Restart (Pn.33 Bit3)
Restart Delay
(Pn.43)
© KEB Antriebstechnik, 1997
All Rights reserved
Voltage
Fist > Pn.19
recovers
yes
Pn.43 Restart
Delay
0,00...100,00 s
Termination of Power-Off function
Drive accelerates again
The following parameters influence the behaviour of the inverter when the mains
voltage returns during the Power-Off function.
Only when parameter Pn.17 and Pn.42 are set to „199" (automatic) the inverter can
restart at voltage recovery. Depending on the application the restart may be sensible
only up to a certain frequency. This frequency is adjusted in Pn.19. If the mains voltage
returns before this adjusted frequency is attained, the inverter restarts after the
expiration of the adjusted restart delay Pn.43 (if ajdusted). Otherwise the drive is
decelerated to standstill.
Bit 3 of Pn.33 determines the behaviour of the drive on attaining 0 Hz.
- If bit 3 is set (see page 8) the modulation is deactivated and the inverter is in
status „PLS". Resetting by opening the control release or reset.
- If bit 3 is not set
- and Pn.19 = 0 Hz the inverter restarts on attaining 0 Hz and after expiration
of the restart delay Pn.43 (if adjusted).
- and Pn.19 <> 0 Hz the inverter modulates with the adjusted boost and is in
status „POFF" (Attention: Motor over heat).
Resetting by opening the control release.
After voltage recovery or attaining of 0 Hz the actual frequency for the time adjusted
here is not changed. The Power-Off function is left afterwards. If the drive is accelerated
directly after voltage recovery higher currents occur than at acceleration from standstill
or constant operation. For this reason the drive may reach the hardware current limit
and may possibly stall. During the time adjusted in Pn.43 the output frequency is kept
constant before the Power-Off function is left. In a way the drive is then in constant
operation before accelerating.
Moreover, the adjustment of different times at several machines helps to prevent that
the mains immediately breaks down again when several machines are accelerated
simultaneously.
Name: Basis
KEB COMBIVERT F4-C
Functional Description
Pn.33
Bit 4
no
Drive decelerates 8 = PLS
to 0Hz
0 = Restart
yes
29.01.98
ANTRIEBSTECHNIK ANTRIEBSTECHNIK
Restart
Drive in status
PLS
no
Drive in status
Pn.19 = 0Hz
P off
Chapter
Date Section
6 9
6
Page
11
11