Amtech Axpert-Eazy Series Instruction Manual page 144

D302: Slip Compensation (Hz)
This parameter is for the auxiliary drive. Set auxiliary motor's rated slip. When setting manually, set
the slip frequency for the auxiliary motor rated load in respect to the base frequency. The output
frequency changes according to the auxiliary motor rated torque. The output frequency will respond
with a time constant of approximately 10msec in respect to the change in the load torque.
D303: DC Brake Start Frequency (Hz)
This is the frequency at which the dc brake will be applied, when the auxiliary drive is selected. To
enable this feature, the stop mode should be ramp down and the dc braking time should not be zero.
If dc braking time is zero, this feature will be disabled.
D304: DC brake Current (%)
This parameter decides the dc brake current when the auxiliary drive is selected.
D305: DC Brake Time (Sec)
This parameter decides the length of time that dc braking is on for the auxiliary drive.
When the stop mode is ramp down and stop command is issued, the output will ramp down with
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deceleration time. When the AC DRIVE output reaches to dc braking start frequency, the dc voltage is
injected to the motor. The amount of voltage and the length of time for which it is applied are decided
by the dc braking current D304 and D305 respectively.
The dc braking is utilized to stop high inertia load forcefully. During dc braking mechanical energy
trapped in rotor due to system inertia will be dissipated as heat in the motor. Hence for safety dc
braking is utilized at lower frequency.
GROUP – 4: LIMITING PARAMETERS
D401: Stall Current Limit (%)
This parameter is for the auxiliary drive. When the AC DRIVE output current crosses the stall current
limit, the output ramps down with current limit deceleration time A209. This is effective only when the
AC DRIVE is operating at set speed. This feature is not active while the AC DRIVE is accelerating or
decelerating. When the current decreases below the programmed value, the AC DRIVE again starts
accelerating to the set speed with current limit acceleration time A208. This feature helps in
maintaining relatively constant output torque characteristics.
Set the current limit as a percentage of auxiliary motor rated current.
D402: Adjustable Over Current Level (%)
This parameter is for the auxiliary drive. Set the upper current level as a percentage of auxiliary
motor rated current. Whenever the AC DRIVE output current exceeds the set value, the AC DRIVE
trips indicating adjustable over current fault. Always set higher side to prevent the unnecessary
tripping of the AC DRIVE during normal operation. This gives the user to program the current level
below the standard inverse time curve. This may be used in cases where excessive torque shocks
can lead to a harmful affect on the machinery.
The default setting of 300% disables this feature and standard inverse time trip remains in effect.
D403: Acceleration Current Limit (%)
This is acceleration current limit for the auxiliary drive and effective only during normal acceleration.
It stops the acceleration, if the motor current exceeds the programmed during acceleration. When the
current reduces below the programmed value the AC DRIVE again starts accelerating to the set
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