Kollmorgen BDS5, Installation And Setup Manual

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G
LOSSARY
BDS5
Glossary-viii
Inrush Current
The current surge generated when a piece of
equipment such as a servoamplifier is connected to an
AC line. This surge is typically due to the impulse
charging of a large capacitor located in the
equipment.
Instability
Undesirable motion of an actuator that is different
from the command motion. Instability can take the
form of irregular speed or hunting of the final rest
position.
Lead Ball Screw
A lead screw which has its threads formed as a ball
bearing race; the carriage contains a circulating
supply of balls for increased efficiency.
Lead Screw
A device for translating rotary motion into linear
motion, consisting of an externally threaded screw
and an internally threaded carriage (nut).
Least Significant Bit
The bit in a binary number that is the least important,
or having the least weight.
Limits
Properly designed motion control systems have
sensors called limits that alert the control electronics
that the physical end of travel is being approached
and that motion should stop.
Linear Coordinated Move
A coordinated move where the path between
endpoints is a line.
Linearity
For a speed control system it is the maximum
deviation between actual and set speed expressed as a
percentage of set speed.
Logic Ground
An electrical potential to which all control signals in a
particular system are referenced.
Loop, Feedback Control
A control method that compares the input from a
measurement device, such as an encoder or
tachometer, to a desired parameter, such as a position
or velocity and causes action to correct any detected
error. Several types of loops can be used in
combination (i.e. velocity and position together) for
high performance requirements.
Loop Gain, Open
The product of the forward path and feedback path
gains.
Loop, PID: Proportional, Integral, and
Derivative Loop
Specialized very high performance control loop
which gives superior response.
Loop, Position
A feedback control loop in which the controlled
parameter is motor position.
Loop, Velocity
A feedback control loop in which the controlled
parameter is mechanical velocity.
Master Slave Motion Control
A type of coordinated motion control where the
master axis position is used to generate one or more
slave axis position commands.
Mechanical Time Constant