6 9
KEB COMBIVERT F4-C
8
Name: Basis
29.01.98
Name: Basis
Chapter Section Page Date
© KEB Antriebstechnik, 1997
All Rights reserved
Functional Description Special Functions
Power-Off-Mode
(Pn.33)
Pn.33 Bit 7654 32 1 0 Function
Value 12864 32 16 8 4 21
automtatic xxxx xx000% (function off)
tripping xxxx xx0180% of measured value
voltage xxxx xx1085% of measured value
at Pn.17=199 xxxx xx1190% of measured value
starting jump xxxx x0xxfrom slip (Standard)
xxxx x1xxfrom load
behaviour at xxxx 0xxximmediate restart, if f
>
Pn.19
voltage recovery xxxx 1xxxPLS
slip control xxx0 xxxxwithout speed detection
xxx1 xxxxwith actual speed detection
increased x x 0 x xxxxat Pn.42>199 immediate
setpoint value x x 1 x xxxxat Pn.42>199 when f<Pn.19
Restart at x 0 x x xxxxoff with control if Pn.42>199 or
0 Hz x1xx xxxxon Pn.18>0
Voltage 0 x x x xxxxon at aktive power off
Stabilisation 1xxx xxxxoff
Parameter Pn.33 bit 2 determines whether the starting jump is calculated from the
slip (active current) or from the load. The standard setting is the slip, however, in case
of high harmonics on the output current it can lead to wrong values. In that case the
starting jump can be calculated from the load.
At activated bit 4 the real slip is determined by way of the recorded actual speed. It is
multiplied with pn.38 and outputted as starting jump. Subsequently only the slip is
controlled, i.e. the output frequency can deviate from the current actual rotary field
frequency only by the pull-out slip of the motor. This mode of operation is to be used
with installed speed measurement, since the results are clearly better.
If bit 5 is activated the DC-link setpoint value equals the switch-off level (Pn.17) until
the output frequency falls below the restart frequency (Pn.19). Up to this point Power
Off is left upon voltage recovery. After the switchover of the setpoint value a controlled
deceleration to 0 Hz takes place (Attention: inverter is still modulation → motor over
heat). Power Off is left only by deactivating the control release.
Slip control (Pn.33 Bit 4)
Starting Jump (Pn.33 Bit 2)
Increased setpoint value
(Pn.33 Bit 5)
Voltage stabilisation during
Power off (Pn.33 Bit 7)
With Bit 7 the output voltage stabilization can be switched off during active Power-Off-
function. This improves the Power-Off performance of motors with high magnetic losses
(e.g. medium frequency motors). However, the switch off should only be used, if the
rated output voltage is stabilized since otherwise a voltage jump occurs at Power-Off.
If an adaption to motors with lower voltage (230 V motor on 400 V inverter) is carried
out, then the output voltage stabilization may never be switched off.
To Next Page
Loading...
Need help?
General