User`s manual

6-4 Motion Mate™ DSM314 for Series 90™-30 PLCs User's Manual – January 2001 GFK-1742A
6
to the home position first, then initiates the find home command. To assist the operator in
jogging to the correct position, a set of alignment marks indicating a close proximity to the home
position is sometimes placed on the machine and machine axis.
Move – (Minus) Home Cycle Example
The next picture shows an example of the Home Position parameter set to Move – (minus). In
this example, the operator jogs the axis until the moveable mark on the machine slide lines up
with the stationary mark on the alignment plate mounted to the machine frame. (Note that the
marks align on the positive side of home position since the Home Position parameter is set to
Move –). Then the operator initiates the find home routine, which causes the axis to move in the
negative direction until the marker pulse occurs.
.
Machine Slide
Moveable Alignment Mark
Direction
+-
Stationary Alignment Mark
Home Position
Negative Overtravel Position
45742.cvs
Positive
Stop
Figure 6-2. Move – (Minus) Home Position Example
Find Home Routine for Move + or Move –
When the find home command (an OFF to ON transition of the
Find Home
%Q bit) is initiated,
the following sequence of events occurs:
1. The axis is accelerated at the
Jog Acceleration
rate
and moved at the configured
Final Home
Velocity
(positive direction for MOVE+, negative direction for MOVE–) until a marker pulse
is sensed. This marker pulse establishes the home reference position.
2. The axis is stopped (at a position past the marker pulse) using the configured
Jog
Acceleration
rate and with the configured
Jog Acceleration Mode
.