Ndrive HL User’s Manual
Glossary of Terms
www.aerotech.com A-7
Rotor
The rotating part of a magnetic structure. In a motor, the rotor is
connected to the motor shaft.
RS-232C
Industry standard for sending signals utilizing a single-ended
driver/receiver circuit. As such, the maximum distance is limited
based on the baud rate setting but is typically 50-100 feet. This
standard defines pin assignments, handshaking, and signal
levels for receiving and sending devices.
RS-274
Industry standard programming language. Also referred to as G-
code machine programming. A command set specific for the
machine tool industry that defines geometric moves.
RS-422
Industry communication standard for sending signals over
distances up to 4000 feet. Standard line driver encoder
interfaces utilize RS-422 because of the noise immunity.
Run-Out
The deviation from the desired form of a surface during full
rotation (360 degrees) about an axis. Run-out is measured as
total indicated reading (TIR). For a rotary stage, axis run-out
refers to the deviation of the axis of rotation from the theoretical
axis of rotation.
Servo System
Refers to a closed loop control system where a command is
issued for a change in position and the change is then verified
via a feedback system.
Settling Time
Time required for a motion system to cease motion once the
command for motion has ended.
Shaft Radial Load
Maximum radial load that can be applied to the end of the motor
shaft at maximum motor speed.
Shaft Run-Out
Deviation from straight-line travel.
Slot-less
Describes the type of laminations used in a motor that eliminates
cogging torque due to magnetic attraction of the rotor to the
stator slots.
Stator
Non-rotating part of a magnetic structure. In a motor, the stator
usually contains the mounting surface, bearings, and non-
rotating windings.
Stiction
Friction encountered when accelerating an object from a
stationary position. Static friction is always greater than moving
friction, and limits the smallest possible increment of movement.
Straightness of Travel
Measure of the side-to-side deviation of a stage as it travels in a
horizontal plane.
Torque
Rotary equivalent to force. Equal to the product of the force
perpendicular to the radius of motion and distance from the
center of rotation to the point where the force is applied.
Torque, Continuous
Torque needed to drive a load over a continuous time.
Torque, Peak
Maximum amount of torque a motor can deliver when the
highest allowable peak currents are applied.
Torque, RMS
Root Mean Square is a mathematical method to determine a
steadfast or average torque for a motor.
Torque, Stall
The maximum torque without burning out the motor.
Total Indicated Reading
The full indicator reading observed when a dial indicator is in
Artisan Technology Group - Quality Instrumentation ... Guaranteed | (888) 88-SOURCE | www.artisantg.com