Lenze E94P PositionServo with MVOB - Manual (Page 51)

S94H201E_13426446_EN L 49
Parameters
5.3.3 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.
5.3.4 Current Limit
The Current Limit setting determines the nominal currents, in amps RMS per phase, that 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. The Current Limit is set equal to the nominal motor phase current by default when a
motor model is selected.
5.3.5 To Change Current Limits
To modify/overwrite the Current Limit place a checkmark in the box. If this box is checked, the parameters
“Current limit”, “8 kHz peak current limit” and “16 kHz peak current limit” can be overwritten. To prevent
the motor from overloading, the “current Limit”, “8 kHz peak current limit” and “16 kHz peak current limit”
shall be set to values no higher than the corresponding current limits of the motor in use.
5.3.6 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.
The Peak Current Limit is set equal to 2.5 times the nominal motor phase current by default when a motor
model is selected. The maximum of 3 times nominal motor phase current can be obtained at 8kHz. 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 limit, refer to section
5.3.5.
5.3.7 Accel/Decel Limits (velocity mode only)
The Accel setting determines the time the motor takes to ramp to a higher speed. The Decel setting
determines the time the motor takes to ramp to a lower speed. If the Enable Accel/Decel Limits is set to
[Disable], the drive will automatically accelerate and decelerate at maximum acceleration limited only by the
current limit established by the Peak Current Limit and Current Limit settings. This parameter is only utilized
when the drive is set to Velocity mode (refer to 5.3.1).
5.3.8 Fault Reset
Fault Reset selects the type of action required to reset the drive after a FAULT condition has been generated
by the drive. On Disable clears the fault when the drive is disabled. This is useful if you have a single drive
and motor connected in a single drive system. The On Enable option clears the fault when the drive is
re-enabled. Choose On Enable if you have a complex servo system with multiple drives connected to an
external controller. This makes troubleshooting easier since the fault will not be reset until the drive is re-
enabled. Thus, a technician can more easily determine which component of a complex servo system has
caused the fault.