Setting Up Parameters
Low Pass Filter Group
Low Pass Filter Enable Check Box
This check box when selected enables a low pass filter applied to the output of the velocity command before the torque compensator. The low pass filter is only active in Pulse and Velocity modes, not Torque Modes.
Low Pass Frequency
This parameter defines the low pass filter
Position Error Integral Group
Position Error Integral Enable Check Box
When selected this enables the Time Constant parameter.
Time Constant
Position Error Integral is a control term which can be used to compensate for the continuous torque required to hold a vertical load against gravity. It is also useful in low speed applications which have high friction.
It also helps maintain accurate command execution during steady state or low frequency torque disturbances (typically less than 10 Hz) or when holding a
The adjustment parameter is Position Error Integral Time Constant which is available in the Tuning View of PowerTools Pro. This parameter determines how quickly the drive will attempt to eliminate the following error. The time constant is in milliseconds and defines how long it will take to decrease the following error by 63%. (3 time constants will reduce the following error by 96%). The range for this parameter is 5 to 500 milliseconds. In certain circumstances the value actually used by the drive will be greater than the value specified in PowerTools Pro because the minimum allowed time constant value is a function of the ‘Response’ parameter. The formula is Min. Time Constant = 1000/Response.
For example, with ‘Response’ set to 50, the minimum time constant value is 1000/50 = 20 msec. A higher time constant value will minimize instability with more compliant loads such as long drive shafts, or spring loads. A lower time constant setting will increase the response and will stiffen the system.
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