Rockwell Automation 1746-HSTP1 Stepper Controller Module/ User Manual - Manual (Page 49)

Publication 999-121 - December 1999
5-14 Configuration and Programming
speed and runs at that speed until the home limit switch is contacted
or marker is detected (depending on which is configured), and then
stops. Without a home proximity limit switch present, the axis speed
moves at the configured starting speed until the home limit switch is
detected. In this instance, the normal acceleration/deceleration and
velocity parameters are disregarded.
The find home command requires the presence of at least one end
limit switch, whether or not a home proximity switch is present. If
only one end limit switch is used, it is the programmer's responsibility
to ensure that the find home command has the correct direction (
+ or
–). The Module does not accept a find home command unless the
corresponding end limit switch is present [CW limit switch for
+/(CW)
command; CCW limit switch for –/(CCW) command]. An incorrect find
home command generates an invalid command input error.
Homing Routines Home to Limit Switch
When Find Home is initiated, it performs the Home at base speed
until the Limit Switch is found. It then stops and sets the position to
zero.
Home to Proximity Limit Switch and Home Limit Switch
When the Find Home command is issued, it homes at the commanded
speed until the proximity switch is reached. It then moves at the base
speed until it reaches the limit switch where it stops and sets the
position to zero.
Home to Proximity Limit Switch and Marker
When the Find Home command is issued, it moves at the commanded
speed until it contacts the proximity switch. It then moves at the base
speed until the marker is found. Upon finding the marker it stops and
sets the position to zero.
If either of the end limit switches is reached during a home operation,
the motor reverses direction and searches for the home limit or home
proximity switch. For this reason, it is important to set the velocity at a
low enough rate to guard against motor lock up during direction
changes.