Emerson P/N 400518-02 manual Modbus, Nvm, Ntc, Pid, Plc

Glossary

mA

Milliamp, which is 1/1000th of an Ampere.

MB

Mega-byte.

MODBUS®

Communication Protocol by Gould, Inc. for industrial communications systems comprised of programmable controller interface units, protocol software and modems. The MDS drive module follows the Modbus specification outlined in the Modicon Modbus Protocol Reference Manual, PI-MBNS-300 Revision G, November 1994.

Module

Function Module

Most Significant Bit

The bit in a binary number that is the most important or that has the most weight.

ms

Millisecond.

NVM

Non-Volatile Memory. NVM stores specifically defined variables as the variables dynamically change. It is used to store changes through a power loss.

NTC

Negative Temperature Resistor

Option Button

Also known as the Radio Button. Round button used to select one of a group of mutually exclusive options.

Opto-isolated

A method of sending a signal from one piece of equipment to another without the usual requirement of common ground potentials. The signal is transmitted optically with a light source (usually a Light Emitting Diode) and a light sensor (usually a photosensitive transistor). These optical components provide electrical isolation.

Output Function

A function (i.e., Drive OK, Fault) that may be assigned to an output line.

Output Line

The actual transistor or relay controlled output signal.

Parameters

User read only or read/write parameters that indicate and control the drive operation. These variables generally hold numerical data defined in the Setup Views.

PE

Protective Earth.

PID

Proportional-Integral-Derivative. An acronym that describes the compensation structure that can be used in many closed-loop systems.

PLC

Programmable Logic Controller. Also known as a programmable controller, these devices are used for machine control and sequencing.

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