II K 4-36
Overview of Software
Speed
act
< 5.15
Torque
act
> 3.17
Time > 3.18
motor stalled
(F19)
The overload phase is set using parameters Arm Cur
Max (3.04) and Overload Time (3.05). The recovery
phase is set using parameter Recovery Time (3.06).
In order not to overload the Motor, the I
2
t-plane of the
two phases have to be identical:
overload phase = recovery phase
(Ia
max
2
- Ia
nom
2
) x overload time = (Ia
nom
2
- Ia
red
2
) x recovery time
In this case it is ensured that the mean value of the
armature current does not exceed 100%. To calculate
the recovery current the formula is rewritten:
)Ia(Ia*
time recovery
time overload
IaIa
2
nom
2
max
2
nomred
−−=
After the overload phase the armature current is
automatically reduced / limited to Ia
red
during the
recovery phase. The current reduction during the
recovery phase is signaled using alarm message
Arm Current Reduced (A6). This message is also
available at the digital outputs.
Shorter overload phases result in higher recovery
currents.
4.5.6 Stall Protection
The stall protection of the motor can be activated with
the Stall Time (3.18) parameter. If the value of this
parameter is 0.0s the stall protection is switched off.
A time >0.0 s switches the stall protection on. The
following conditions must be fulfilled to trip the mon-
itor:
The actual speed value is smaller than the value in
Zero Speed Lev (5.15) and the actual torque value is
bigger than the value in Stall Torque (3.17) for a time
longer than the value in Stall Time (3.18).
4.5.7 Flux Adaptation
The flux characteristic of the field is not linear to the
increase in speed in the field weakening mode. Every
field has a characteristic of its own within certain
limits. This characteristic can be emulated by means
of the parameters Field Cur 40 % (4.07), Field Cur
70% (4.08) and Field Cur 90% (4.09). The character-
istic can be determined automatically by means of a
service procedure in the parameter Contr Service
(7.02).
In the case of manual parameterization, make sure
that the parameter values are plausible i.e. the value
in the parameter Field Cur 40 % (4.07) must be set to
a value smaller than the value in Field Cur 70%
(4.08), its value in turn must be smaller than the value
in Field Cur 90% (4.09). Otherwise, the warning Par
Setting Conflict (A16) will be generated.
$OW6SHHG.3
$OW6SHHG7,
$OW$FFHO5DPS
$OW'HFHO5DPS
6SHHG5HJ.3
6SHHG5HJ7,
$FFHO5DPS
'HFHO5DPS
to
Ramp generator
respectively
Speed controller
Select switch over event for parameter set 2 in parameter
$OW3DU6HO
:
Parameter set
DOZD\V
active
Parameter set 2
DOZD\V
active
2 = makro depend
3 = Sp < Lev1
4 = Sp < Lev2
5 = Sp Err<Lev1
6 = Sp Err<Lev2
3DUDPHWHUVHW
3DUDPHWHUVHW
0 = disable
1 = enable
depends on the selected macro
if Speed Actual < Speed Level 1 (5.16) parameter set 2 aktive
if Speed Actual < Speed Level 2 (5.17) parameter set 2 aktive
if Speed Error < Speed Level 1 (5.16) parameter set 2 aktive
if Speed Error < Speed Level 2 (5.17) parameter set 2 aktive
n
t
Speed Reg KP (5.07)
Speed Reg TI (5.08)
Decel Ramp (5.10)
effective
Speed Reg KP (5.07)
Speed Reg TI (5.08)
Accel Ramp (5.09)
effective
switching
depends on
Speed Lev 1/2
Alt Speed KP (5.22)
Alt Speed TI (5.23)
Alt Decel Ramp (5.25)
effective
Alt Speed KP (5.22)
Alt Speed TI (5.23)
Alt Accel Ramp (5.24)
effective
4.5.8 Alternative Parameters for the Speed
Controller
A second parameter set is available for the speed
controller (Alternative Parameters), which can be
activated through events. The speed controller pa-
rameters KP and TI and the parameters for the
accelerating and deccelerating ramps are switched
over. Depending on the speed actual value or the
speed deviation (difference between speed actual
and speed reference) the behaviour of the speed
controller can be influenced. In this way different
behaviour during acceleration and decceleration can
be parameterized easily.
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