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#L010120
November 2001
Section 2: Functions
Move Number of Steps:
The move number of steps command causes the motion to start in the direc-
tion last specified. This command will move the motor the number of steps given. (Range: 0 to 8388607)
Soft Limit Switches:
These switches are used exclusively when homing to a datum point. If positioned
properly with the appropriate parameters, it causes the motor to ramp down to the base speed before
encountering the home limit switch.
Move to Position:
The move to position command specifies the next absolute position to go to. The
PCL501(PC) automatically sets the direction and number of steps needed to go to that position.
(Range: -8388608 to +8388607)
Limit Switch Inputs:
The limit switch inputs are internally pulled up by a resistor making them normally
+5 volts. To activate the input, the pin must be grounded to (0VDC) on the terminal block.
Hard Limit Switches:
When a hard limit switch is encountered, the motion will stop. The position counter
will also cease counting. Hard limits are intended as an emergency stop for your system. It should not be
used to do any indexing type functions.
Home Limit Switch:
This switch is used to establish the reference position designated “home” in home
to home limit or home to soft, home limit.
Home to Soft, Home Limit (2 Switch Operation):
This type requires two grounding type limit switches
called home and soft. The first limit switch soft will decelerate the motor down to base speed. It will con
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tinue to run at base speed until it receives a home limit switch input causing the motor to stop. The home
limit switch only activates after a soft limit is sensed. The soft limit is not bidirectional, meaning that it will
work in only one direction as specified. The soft limit switch will work for any type of motion. The home
limit switch will work only for home motions.
Note: Whenever a soft limit switch is activated, the motor will decelerate and run at base speed. Be sure
to come back passed the soft limit switch to set any origins, otherwise the motor will decelerate as it goes
passed the soft limit switch.
Home to Home Limit
: This type of homing differs in that only one limit switch is needed. The home limit
switch in this case causes the motor to ramp down to base speed, reverse direction and continue until
the limit switch is released. This is a good way to compensate for any backlash in the system. It is also
useful for minimizing the number of limit switches needed for homing.
Set Position:
The set position command sets the position register to a designated value. The number
will be the new absolute position of the motor. The default value is 0. (Range: -8388608 to +8388607)
July 2018
L010121
