Kollmorgen BDS5, Installation And Setup Manual

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G
LOSSARY
BDS5
Glossary-x
Open Collector
A term used to describe a signal output that is
performed with a transistor. An open collector output
acts like a switch closure with one end of the switch
at ground potential and the other end of the switch
accessible.
Open-Loop System
A system where the command signal results in
actuator movement but, because the movement is not
sensed, there is no way to correct for error. Open
loop means no feedback.
Operator Interface
A device that allows the operator to communicate
with a machine. This device typically has a keyboard
or thumbwheel to enter instructions into the machine.
It also has a display device that allows the machine to
display messages.
Optically Isolated
A system or circuit that transmits signals with no
direct electrical connection. Used to protectively
isolate electrically noisy machine signals from low
level control logic.
Oscillation
An effect that varies periodically between two values.
Overshoot
The amount of the parameter being controlled
exceeds the desired value for a step input.
Phase-Locked Servo System
A hybrid control system in which the output of an
optical tachometer is compared to a reference square
wave signal to generate a system error signal
proportional to both shaft velocity and position
errors.
Phase Margin
The difference between 180 degrees and the phase
angle of a system at the frequency where the open
loop gain is unity.
PID
Proportional-Integral-Derivative. An acronym that
describes the compensation structure that can be used
in a closed-loop system.
PLC
Programmable Logic Controller. An industrial
control device that turns on and off outputs based
upon responses to inputs.
PMDC Motor
A motor consisting of a permanent magnet stator and
a wound iron-core rotor. These are brush type motors
and are operated by application of DC current.
Point to Point Move
A multi-axis move from one point to another where
each axis is controlled independently. (No
coordination between axes is required.)
Pole
A frequency at which the transfer function of a system
goes to infinity.
Pole Pair, Electromechanical
The number of cycles of magnetic flux distribution in
the air gap of a rotary electromechanical device.
Position Error
The difference between the present actuator
(feedback) value and the desired position command
for a position loop.
Position Feedback
Present actuator position as measured by a position
transducer.