Nord Drivesystems SK 300P Series - Page 106

NORDAC ON / ON+ (SK 3xxP) – Manual with installation instructions
106 BU 0800 en-4521
P555 P-limit chopper S
Setting range
5 … 100 %
Factory setting
{ 100 }
Description
"
Chopper power limit
“. With this parameter it is possible to program a manual (peak)
power limit for the braking resistor. The switch-on delay (modulation level) for the
chopper can only rise to a certain maximum specified limit. Once this value has been
reached, irrespective of the level of the link circuit voltage, the inverter switches off the
current to the resistor.
The result would be an overvoltage switch-off of the FI.
The correct percentage value is calculated as follows:
%100*
*
[%]
2
max
max
U
PR
k
BW
=
R =
Resistance of the braking resistor
P
maxBW
=
Momentary peak power of the braking resistor
U
max
=
FI chopper switching threshold
3~ 400 V
⇒ 1000 V DC
P556 Braking resistor S
Setting range
1 ... 400 Ω
Factory setting
{ 120 }
Description
Value of the braking resistor for calculation of the maximum brake power in order to
protect the resistor.
Note
Once the maximum continuous output P557 including overload (200 % for 60 s) is
reached, an I
2
t limit error E003.1 is triggered. For further details see P737.
P557 Brake resistor type S
Setting range
0.00 ... 320.00 kW
Factory setting
{ 0.00 }
Description
Continuous power (nominal power) of the resistor, to display the actual utilisation in
P737. For a correctly calculated value, the correct value must be entered into P556
and P557.
Setting values
0.00 Monitoring disabled
P558 Flux delay S P
Setting range
0, 1, 2... 5000 ms
Factory setting
{ 1 }
Description
ASM
The ISD control can only function correctly if there is a magnetic field in the
motor. For this reason, a DC current is applied before starting the motor to
provide excitation of the stator winding. The duration depends on the size of
the motor and is automatically set in the factory setting of the FI. For time-
critical applications the flux delay can be set or disabled.
PMSM
When used with PMSM, the dwell time can be set via this parameter during
rotor position identification using the dwell method. Total dwell duration = 2.5
x P558 [ms]
Note
Setting values that are too low can reduce the dynamics and starting torque.
Setting values
Value Meaning
0
Switched off
1
Automatic calculation
2 … 5000
Time set in [ms]