Rockwell Automation 1771-QB Linear Pos. - Manual (Page 172)

Glossary of Terms & Abbreviations
Appendix A
AĆ3
Feedback Resolution: The smallest increment of dimension that the feedback
device can distinguish and reproduce as an electrical output.
Feedback Signal: The measurement signal indicating the value of a directly
controlled variable, which is compared to a commanded value to obtain
the corrective error signal.
Feedforward Control: Converting information on upstream conditions into
corrective commands to minimize the effect of disturbances.
Firmware: A series of instructions in read-only memory. These instructions are
for internal processor functions only.
Forward Motion: Axis movement in a positive direction along a coordinate
axis.
Gain: The ratio of the output of a system to its input.
Incremental Position: A position described by its distance from the previous
position along a coordinate axis.
Initialize: To cause a program or hardware circuit to return to an original state.
Integral Control: The component that causes an output signal to change as a
function of the error signal and time duration.
Instability: The state or property of a system where there is an output for which
there is no input.
Instruction: A statement that specifies an operation and the values or location
of its operands.
Integrator: A device that integrates an input signal, usually with respect to
time.
Interface: The boundary between two systems.
I/O: Input/Output
ips/s: Inches per second per second.
ISA: Instruments Society of America
Jog: A control function that provides for the momentary operation of a
servo-valve or motor for manual control of axis motion.
Linear Displacement Transducer: A position-sensing transducer mounted
along an axis.
Loop: A signal path.