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110
SPX advanced – description of parameters
SPX ADVANCED APPLICATION MANUAL
SVCH0203—October 2017 www.eaton.com
Code
ID
Parameter
Notes
P1.8.4.6
605
U/f Curve, middle point voltage “U/f mid voltg”
If the programmable U/f curve has been selected with the parameter U/f ratio this
parameter defines the middle point voltage of the curve. See also parameter Middle
point frequency.
When the programmable U/f curve is selected this value is set to 10 %
(of motor nominal voltage).
P1.8.4.7
606
Output voltage at zero frequency “Zero freq voltg”
This parameter defines the zero frequency voltage of the U/f curve. The default value
is unit size dependent.
If the value of parameter U/f Ratio
Select is changed this parameter
is set to zero.
Code
ID
Parameter
Notes
P1.8.5.1
617
Current control P gain “CurrentControlKp”
Sets the gain for the current controller. The controller generates the voltage vector
reference to the modulator. The gain is also used in open loop flying start. When the
Sine filter parameter (parameter P6.7.5 in the System menu) has been set to Connected
the value of this parameter is changed to 20.00 %.
The value is also identified when using a PMS motor and making identification run
with rotating motor. At low speed the motor values may increase up to 300 %. At high
speed motor gain and motor with sine filter may have gain values of 10...40 %.
P1.8.5.3
657
Current control Ti “CurrentControlTi”
Current controller integrator time constant.
P1.8.5.3
619
Slip adjust “Slip adjust”
The motor name plate speed is used to calculate the nominal slip. This value is used
to adjust the voltage of motor when loaded. The name plate speed is sometimes
inaccurate and this parameter can therefore be used to trim the slip. Reducing the slip
adjust value increases the motor voltage when the motor is loaded.
P1.8.5.4
626
Acceleration compensation “Accel.Compens.”
Sets the inertia compensation to improve the speed response during acceleration and
deceleration. The time is defined as acceleration time to nominal speed with nominal
torque. This function is used when the inertia of the system is known to achieve the
best speed accuracy when reference is changed.
Acceleration compensation is added to TorqueReferenceActual i.e. torque is added
after speed controller. The speed controller can, therefore, be tuned only for speed
error and the acceleration compensation makes sure that the system inertia does not
affect the speed controller.
SPC Out
Freq.Out
Acceleration compensation not in use
5.8.2 Close loop settings