Control Techniques FM-3, Reference Manual

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FM-3 Programming Module Reference Manual
Registration Index
A Registration Index is used in applications where the motor must move until an object is
detected and then move a specific distance from the point of detection, such as finding a
registration mark and moving a distance beyond.
The Registration Index consists of two parts. The first part accelerates the motor to the target
velocity and continues at this velocity until it receives a registration trigger (sensor or analog).
Upon receipt of a registration trigger, the registration offset will be executed at the target
velocity. The Sensor Limit Distance Hit source can be used to turn on an output, if a sensor
input or analog limit is not received within the Limit Distance. A registration window can
also be used to determine the validity of a registration trigger. If a registration trigger is
received outside of the registration window, it will be ignored.
Rotary Plus and Rotary Minus Indexes
Rotary Plus and Rotary Minus Indexes provide forced directional control of moves to
absolute positions. The position entered for a Rotary Plus or Minus type index must be within
the rotary range (i.e. 0
≤
Position < Rotary Rollover Point). All other parameters function the
same as they do with absolute indexes. An Absolute Index is a direct move to a specific
position, regardless of the starting point. A Rotary Plus Index moves to the specified position,
but is forced in a positive direction. Similarly, a Rotary Minus index moves to the specific
position, but is forced in a negative direction.
Rotary Plus and Minus Indexes are usually used in rotary applications, therefore the rotary
rollover feature on the Setup - Position view in the PowerTools Pro software must be enabled
to use them.
1. In the following examples the term “D” = (absolute position specified) - (current
position). If “D” is negative, motion in the negative direction is implied.
2. In the following examples the Rotary Rollover parameter on the Setup - Position view is
set to 360.00°. This means that with each revolution of the motor (or rotary table),
feedback will count up to 359.99°, then roll over to Ø°.
Indexes with Rotary Rollover Enabled
Incremental move distances can be outside of the rotary rollover range. See the Setting
Up Parameters section for an explanation of Rotary Rollover.
Example 1: If the starting position is at Ø° and 720° is the specified distance, an
Incremental index would move 2 revolutions in the positive direction. At the completion
of this index the motor position would be Ø°.
Absolute indexes will take the shortest path to the specified position. Absolute index
positions must be within the rotary rollover range.
Example 2: If the starting position is at 90° and 80° is the specified position, an Absolute
index would travel 10° in the negative direction. At the completion of this index the
motor position would be 80°.