Technical information

186
230V FX Series Positioning Drive Reference Manual
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. Usually indicated as the forward path gain value
only.
Loop, PID: Proportional, Integral and Derivative Loop
Specialized very high performance control loop which accommodates for three factors associated with
machine control to deliver 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 the position or
velocity commands for one or more slave axes.
Mechanical Time Constant
The time for an unloaded motor to reach 63.2 percent of its final velocity after the application of a step
function velocity command.
MOS and CMOS
Metal Oxide Semiconductor and Complementary MOS.
Most Significant Bit
The bit in a binary number that is the most important or that has the most weight.
Motor, AC
A device that converts electrical alternating current into mechanical energy. Requires no commutation
devices such as brushes. Normally operated off commercial AC power. Can be single or multiple phase.
Motor, AC Asynchronous or Induction
An AC motor in which speed is proportional to the frequency of the applied AC. Requires no magnets or
field coil. Usually used for non-precise constant speed applications.
Motor, AC Synchronous
Another term for brushless DC or AC motor which uses rotor magnets.
Motor, DC
A device that converts electrical direct current into mechanical energy. Usually refers to a motor with a
brush commutator on the stator.