Lenze S94P01G Position Servo - Manual (Page 43)

S94P01G
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Parameters
5.3.2 Drive PWM frequency
This parameter sets the PWM carrier frequency. Frequency can be changed only when
the drive is disabled. Maximum overload current is 300% of the drive rated current when
the carrier is set to 8kHz. It is limited to 250% at 16kHz.
5.3.3 Current Limit
The CURRENT LIMIT setting determines the nominal currents, in amps RMS per phase,
which output to the motor phases. To prevent the motor from overloading, this parameter
is usually set equal to the motor nominal (or rated) phase current. If MotionView (6.04)
or higher is used, the Current Limit is set equal to the nominal motor phase current by
default when a motor model is selected. To modify this parameter, refer to section 5.3.23.
5.3.4 Peak Current Limit (8 kHz and 16 kHz)
Peak Current Limit sets the motor RMS phase current that is allowed for up to 2
seconds. After this two second limit, the drive output current to motor will be reduced
to the value set by the Current Limit parameter. When the motor current drops below
nominal current for two seconds, the drive will automatically re-enable the peak current
level. This technique allows for high peak torque on demanding fast moves and fast
start/stop operations with high regulation bandwidth. If 8 kHz is used for Drive PWM
frequency, use the parameter 8 kHz Peak Current Limit, otherwise, use 16 kHz Peak
Current Limit.
If MotionView (6.04) or higher is used, the Peak Current Limit is set equal to 2.5 times
the nominal motor phase current by default when a motor model is selected. To prevent
motor from overloading, the Peak Current Limit shall be set no higher than the maximum
motor current. Otherwise, the motor may be damaged due to overheating. To modify
this parameter, refer to section 5.3.23.
5.3.5 Analog Input Scale (current scale)
This parameter sets the analog input sensitivity for current reference used when the
drive operates in torque mode. Units for this parameter are A/Volt. To calculate this
value use the following formula:
Iscale = Imax / Vin max
Imax maximum desired output current (motor phase current RMS)
Vin max max voltage fed to analog input at Imax
Example: Imax = 5A (phase RMS)
Vin max = 10V
Iscale = Imax / Vin max
= 5A / 10V = 0.5 A / Volt (value to enter)
5.3.6 Analog Input Scale (velocity scale)
This parameter sets the analog input sensitivity for the velocity reference used when the
drive operates in velocity mode. Units for this parameter are RPM/Volt. To calculate this
value use the following formula:
Vscale = VELOCITYmax / Vin max
VELOCITYmax maximum desired velocity in RPM
Vin max max voltage fed to analog input at Velocity
max
Example: VELOCITYmax = 2000 RPM
Vin max = 10V
Vscale = VELOCITYmax / Vin max
= 2000 / 10V
= 200 RPM / Volt ( value to enter)