Example programs, Chapter – Rockwell Automation 1771-QA Stepper Positioning Assembly User Manual User Manual

Page 79

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Chapter

4

Publication 1771-UM002A–EN–P – May 2000

Example Programs

Two example programs are presented in this chapter. The purpose of
these programs is to illustrate the procedure and documentation that
should be used and to explain the relationship between the ladder
diagram program, positioning profile(s) and move data.

The ladder diagram program presented in this section is written for a
1-axis machine application having a positioning profile of 10 moves.
Values for ramp time, final rate, decel time and final position for
each move can be programmed using an industrial terminal and a
Mini-PLC-2/15 or PLC-2/30 programmable controller in a local or
remote system configuration. The program would have to be
modified (substitute multiple get/put instructions for file-to-file
move instructions) in order to use a PLC-2/20 controller. The
following operational functions can be selected when programming
the positioning profile.

Controlled stop

Reset

Initialization preset

Software jog forward

Software jog reverse

Jog rate

Type of profile

Profile length

Profiles that are longer than 10 moves (one moveset) can be
programmed by adding movesets. This can be done by
programming additional file-to-file move instructions and entering
move data in their corresponding files. Also, user-supplied inputs to
the pulse output expander module can provide the following options:

Hardware jog forward

Hardware jog reverse

Hardware stop (E-Stop)

The program is written for a 1-axis machine application and requires
one Stepper Controller Module (cat. no. 1771-M1) and one Pulse
Output Expander Module (cat. no. 1771-OJ). The user-supplied
stepper translator that interfaces with the pulse output expander
module should accept low true inputs.

General

1-Axis Program

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