Menu 3: Speed Feedback And Speed Control - Emerson Mentor MP Advanced User's Manual

Parameter Keypad and Advanced parameter Serial comms
Performance Menu 3
format
protocol
structure descriptions
Parameter description
5.4

Menu 3: Speed feedback and speed control

Speed accuracy and resolution
Digital reference resolution
When a preset speed is used the reference resolution is 0.1 rpm. Improved resolution can be obtained by using the precision reference (0.001 rpm).
Analog reference resolution
The analog input has a maximum resolution of 14bits plus sign. The resolution of the reference from analog inputs 2 or 3 is 10bits plus sign.
Analog feedback resolution
The resolution for both Armature voltage and tachometer feedback is 10bit plus sign.
Accuracy
With encoder feedback the absolute speed accuracy depends on the accuracy of the crystal used with the drive microprocessor. The accuracy of the
crystal is 100ppm, and so the absolute speed accuracy is 100ppm (0.01 %) of the reference, when a preset speed is used. If an analog input is used
the absolute accuracy is further limited by the absolute accuracy and non-linearity of the analog input. If analog feedback is used the accuracy is even
further limited.
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Mentor MP Advanced User Guide
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