Specifications

37
Pulse rate
The frequency of step pulses applied to
a step motor. The pulse rate multiplied by
the resolution of the motor yields the
rotational speed of the motor in
revolutions per second. The rotations per
second multiplied by the lead of the
screw and divided by the gear ratio
provides the extension speed in inches
per second.
Radial load
A load on the side of the actuator
extension tube. Normally considered to
be detrimental to the life of the unit. Also
referred to as “side load”.
Resolution
The smallest positioning increment that
can be achieved. This depends on the
lead of the screw, gear ratio and using
either full, half or micro-stepping
controls.
Retracted length
Minimum length of the actuator in its
retracted state.
RS-232
A data communications standard that
encodes a string of information on a
single line in a time sequential format.
Side load
Force applied perpendicular to the axis
of the extension tube. (see radial load)
Static load
The maximum non-operating load
capacity.
Stroke length
The total travel of the extension tube
from full retract to full extend.
Tension load
A load that would tend to stretch the
actuator.
Thermal dissipation
The transfer of heat from a system to its
environment.
Trapezoidal motion profile
A type of motion profile in which the
actuator is linearly accelerated to and
decelerated from the desired running
speed to provide the desired incremental
move time. See page 33 for an example.
Triangular motion profile
A type of motion profile in which the
actuator is linearly accelerated and
decelerated to provide the desired
incremental move time. All of the
movement is either in acceleration or
deceleration with no steady run speed.
See page 33 for an example.
Limit switch
A switch used to limit motion or travel in
a particular direction.
Load
The force axially imposed on the
actuator
Logic ground
An electrical potential to which all control
signals in a particular system are
referenced.
Micro-stepping
A control technique that proportions
current in stepmotor windings to provide
additional intermediate positions
between poles. It also provides higher
positional resolution and smooths
rotation over wide speed ranges. It
provides somewhat lower torque than full
or half-step operation.
Open collector
A transistor which is connected to
operate like a single pole single throw
(SPST) switch. The load must be
connected between the open collector
and the voltage source.
Open loop
A motion system where no external
feedback devices are used to provide
position or velocity correction
information.
PC
Abbreviation for personal computer.
Ramping
The acceleration and deceleration of a
step motor. Ramping is required to
overcome the inertia of the load without
stalling the step motor.
Reed switch
A sealed magnetically operated
mechanical switch. The switch either
opens or closes when passing through a
magnetic field.
Repeatability
The degree to which the positioning
accuracy for a given move can be
duplicated given the same control
signals and loads.
Wrong
Actuator Axis