Kollmorgen BDS5, Installation And Setup Manual

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BDS5 G
LOSSARY
Glossary-xiii
SPS
Steps-Per-Second. A measure of velocity used with
stepping motors.
Stall Torque
The torque available from a motor at stall or zero
rpm.
Static Torque
The angle the shaft rotates upon receipt of a single
step command.
Stator
The non-rotating part of a magnetic structure. In a
motor the stator usually contains the mounting
surface, bearings, and non-rotating windings or
permanent magnets.
Stiffness
The ability to resist movement induced by an applied
torque. It is often specified as a displacement curve,
indicating the amount a motor shaft will rotate upon
application of a known external force when stopped.
Synchronism
A motor rotating at a speed correctly corresponding
to the applied step pulse frequency is said to be in
synchronism. Load torques in excess of the motor's
capacity (rated torque) will cause a loss of
synchronism.
Tachometer
An electromagnetic feedback transducer which
produces an analog voltage signal proportional to
rotational velocity. Tachometers can be either brush
or brushless.
Tachsyn
A brushless, electromagnetic feedback transducer
which produces an analog velocity feedback signal
and commutation signals for a brushless servo motor.
The tachsyn is functionally equivalent to hall sensors
and a tachometer.
Torque
The 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 Constant
A number representing the relationship between
motor input current and motor output torque.
Typically expressed in units of torque/amp.
Torque Ripple
The cyclical variation of generated torque given by
the product of motor angular velocity and number of
commutator segments.
Torque-to-Inertia Ratio
Defined as a motor's torque divided by the inertia of
its rotor, the higher the ratio the higher the
acceleration will be.
Transducer
Any device that translates a physical parameter into
an electrical parameter. Tachometers and encoders
are examples of transducers.
Transfer Function
The ratio of the Laplace transforms of system output
signal and system input signal.
Trapezoidal Profile
A motion profile in which the velocity vs. time profile
resembles a trapezoid. Characterized by constant
acceleration, constant velocity, and constant
deceleration.