PMAC Product Guide I-Variables Setup Before attempting to move any motor, it is essential to set up the corresponding I-Variables that will determine, for example, how fast the motor will accelerate, how fast it will move, and how well the motion will be performed based on its tuning parameters. Note: The EZ-PMAC Setup Software has dedicated screens for the configuration of each I-Variable. The Catalog function of the EZ-PMAC Setup Software has the description of each I-Variable. The section below is a summary of the I-Variables involved in each feature. For more information, refer to the complete I-Variables description chapter. Some I-Variables might be expressed as, for example, Ix00.
In the case of a motor I-Variable, x stands for the motor number in the range of 1 through 8. In the case of a coordinate system I-Variable, x stands for the coordinate system number, also in the range of 1 through 8. Note: Completely reset PMAC before start the I-Variables setup process. The $$$*** online command resets all PMAC I-Variables to factory defaults. This global reset command also deletes any motion program or PLC program present in memory before reset. Motor Definition I-Variables Ix00 - Motor x Activate : For controlling an actual physical motor, this PMAC motor I-Variable should be set to one.
If there is no physical motor associated with this PMAC motor x, then this variable should be set to zero which is the case when using the encoder input or DAC output of this motor for a different purpose than controlling an actual physical motor. Motor Safety I-Variables Ix11 - Motor x Fatal Following Error Limit : This variable setup the maximum number of counts of allowed following error before the motor is shutdown. Warning: Setting Ix11 to zero can lead to a dangerous motor runaway condition. For example, if the encoder feedback information is lost, PMAC will shutdown the motor when the following error exceeds Ix11 and so will prevent the motor to runaway in an uncontrollable fashion.
Ix13 - Motor x + Software Position Limit : This variable determines the maximum allowed range of motion in the positive direction. Enabling this function is useful when no actual end-of-travel limit switches are used. Ix14 - Motor x - Software Position Limit : This variable determines the maximum allowed range of motion in the negative direction. Enabling this function is useful when no actual end-of-travel limit switches are used. Ix15 - Motor x Abort/Lim Deceleration Rate : This parameter sets the deceleration rate used when a programmed motion is aborted either by the A abort command or when a maximum position limit is reached. Ix16 - Motor x Maximum Velocity :
This parameter setup the maximum allowed velocity for a motor performing a linear move commanded from a motion program. This maximum value is not observed if variable I13 is greater than zero. Programming PMAC 51