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Why the encoder card VW3A3401 is not provided with speed measurement and limit in RPM or pulse/sec? instead it is provided with Pulse/Rev?

The term, pulse per revolution (pulse/rev) is called as resolution and it is deciding the accuracy level. Also speed is calculated by drive from the number of pulses received from encoder. As per our understanding none of the encoder will give direct speed feedback in RPM and I do not find any of encoder is mentioning the speed in pulses / second in encoder specification. 

The encoder card is always mentioned with pulse per revolution (pulse/rev). It is the specification of resolution, means encoder card accuracy limit. As encoder card is concerned, there is no separate maximum speed limit applicable, it will consider the maximum speed limit related to the Altivar series VFD, where it is installed. But the encoder will have the maximum speed limit based on its mechanical design, which will be mentioned in encoder datasheet by the manufacturer. The parameter PGI is indicating the pulse per revolution, not the maximum speed. Based on this parameter the drive will keep on counting the pulses and calculate the speed of the encoder shaft and motor.
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