PSO Input Frequency Specifications

PSO supports a maximum input frequency of 100 MHz. But, the type of incremental position feedback signals that you are tracking and how these inputs are connected to your drive have an effect on the maximum input frequency. Refer to the table that follows to see how different operations change the maximum input frequency limits.

Table: PSO Input Frequency Limits

Operation Limit (million counts per second) Cause

Documentation

Tracking a square wave primary or auxiliary encoder input

40

The maximum supported encoder input frequency is 10 MHz, which is 40 million counts per second

Drive hardware manuals (see Manuals & Help Files online)

  • Tracking a sine wave primary or auxiliary encoder input

  • Tracking an absolute encoder with sine wave incremental signals

100

Emulated quadrature signals in the drive that are generated from the sine wave signals can be up to 100 MHz

PrimaryEmulatedQuadratureDivider Parameter or AuxiliaryEmulatedQuadratureDivider Parameter

  • Tracking auxiliary encoder input signals from another Automation1 drive that is using Drive Encoder Output

  • Tracking SYNC port signals from another Automation1 drive that is using Drive Encoder Output

25

The maximum supported frequency for the Drive Encoder Output feature is 25 MHz

Configuring the Drive Encoder Output section on the Device Functions page

Tracking the drive pulse stream when using part-speed PSO

95

The maximum frequency for the pulse stream feature is 95 MHz

Pulse Stream section on the Device Functions page

MX Quadrature Warnings and Errors

High-frequency changes in the velocity of the axis can cause the rate of quadrature generation to exceed the maximum allowable limit, even if the commanded velocity is within limits. This occurs because the quadrature generation for sine wave encoder signals is faster than the data collection rate of the drive.

Use the MxQuadratureWarning and MxQuadratureError status items in the AuxililaryFeedbackStatus and PrimaryFeedbackStatus enums to identify if the axis is violating the maximum quadrature generation rate. See AeroScript Enums. The descriptions of these status items are as follows:

  • MxQuadratureWarning: The axis is violating the maximum allowable quadrature generation rate. The controller can momentarily buffer extra encoder counts, but while the buffer is doing this, quadrature generation is delayed.

  • MxQuadratureError: Encoder counts are lost because the buffer in MxQuadratureWarning is full and overflowed.