Feedback Interface Types

Feedback interface technologies include:

Other modern feedback interfaces supported are:

Hiperface

and

Hiperface

DSL (by Stegmann) and

EnDat

2.1 and

EnDat

2.2 (by Heidenhain). The Usage column for a feedback attribute is based on the context of the Feedback Type. Abbreviations for the various Feedback Types are defined in this table:

Feedback Type abbreviations

Tamagawa (TG), Nikon (NK), and Stahl SSI (SL) are serial interface protocols for encoders. Track Section (TS) and Track Mover (TM) are applicable to track-based systems. The position feedback characteristics of the track split between track sections and track movers. Section electronics determine feedback resolution and the feedback range for the Track Section component of the feedback electronics.

This section defines the minimal set of required attributes to support CIP Motion device interchangeability. This guarantees that there is sufficient parametric data provided by the controller for any CIP Motion compliant drive to effectively interface to a wide range of feedback device types.

Multiple feedback device interfaces are currently defined by the Motion Control Axis per axis to serve specific control or master feedback functions. These feedback devices are accessed using their assigned logical channels, for example, Feedback 1 and Feedback 2. Each logical feedback channel is mapped to a physical feedback interface port of the device, for example Port 1, and Port 2.

Logical Feedback Channel Control Functions

When the Control Mode is set to something other than No Control, Feedback 1 is associated with the motor mounted feedback device while Feedback 2 is associated with the load-side or machine mounted feedback device. Feedback 1 is always required for PM Motor commutation.

When Control Mode is set to No Control for a Motion Control Axis, different logical feedback channels can be used as the master feedback source, for example, Feedback 1 and Feedback 2. Generally, Feedback 1 is used.

For

Rockwell Automation

devices Feedback 3 is used to provide a redundant logical feedback channel for Feedback 1 while Feedback 4 is used to provide a redundant logical channel for Feedback 2.

To minimize the length of the feedback attribute tables below, the letter

n

in the generic Feedback n attribute name is used to specify the associated feedback channel number. Valid channel numbers for open standard feedback attributes of the Motion Control Axis are 1, 2, 3 and 4.

Attribute IDs are assigned based on the channel number. Support for feedback interface channels 1, 2, 3 and 4 are optional in the device implementation. If no feedback interface channel is present in the device the associated set of feedback channel attributes are not applicable.

However, if hardware support for any of these feedback channels is available in a given device, these attributes are clearly applicable in the implementation and will follow the Usage rules. A Usage rule of 'Req - E' or 'Opt - E' indicates that the attribute is generally applicable to all Device Control Codes where the feedback channel itself is applicable, hence the 'E' for Encoder.

If a specific logical feedback channel, feedback n, is not applicable based on the current feedback configuration, then attributes for feedback n are not applicable; no feedback configuration attributes for that channel are set by configuration software, nor are any such attributes sent to the drive device. This table outlines these rules: