ROC827 Instruction Manual

M

 

 

 

m

Meter.

 

 

mA

Milliamp(s); one thousandth of an ampere.

 

 

MAC Address

Media Access Control Address; a hardware address that uniquely identifies each node of

 

a network.

 

 

Manual mode

For a ROC, indicates that the I/O scanning has been disabled.

 

 

MAU

Medium Attachment Unit.

 

 

MCU

Master Controller Unit.

 

 

Modbus

A popular device communications protocol developed by Gould-Modicon.

 

 

MPU

Micro-Processor Unit.

 

 

mm

Millimeter.

 

 

MMBTU

Million British Thermal Units.

 

 

msec

Millisecond, or 0.001 second.

 

 

MVS

Multi-Variable Sensor. A device that provides differential pressure, static pressure, and

 

 

 

temperature inputs to a ROC for orifice flow calculations.

 

 

mV

Millivolts, or 0.001 volt.

 

 

mW

Milliwatts, or 0.001 watt.

 

 

N

 

 

 

NEC

National Electrical Code.

 

 

NEMA

National Electrical Manufacturer’s Association. See http://www.nema.org.

 

 

O

 

 

 

OH

Off-Hook modem communications signal.

 

 

Off-line

Accomplished while the target device is not connected (by a communications link). For

 

 

 

example, “off-line configuration” refers to configuring an electronic file that is later loaded

 

into a ROC.

 

 

Ohms

Units of electrical resistance.

 

 

On-line

Accomplished while connected (by a communications link) to the target device. For

 

 

 

example, “on-line configuration” refers to configuring a ROC800-Series unit while

 

 

 

connected to it, so that you can view the current parameter values and immediately load

 

new values.

 

 

Opcode

Type of message protocol the ROC uses to communicate with the configuration software,

 

as well as host computers with ROC driver software.

 

 

Operator

Also LOI or Local Port; the serial EIA-232 (RS-232) port on the ROC through which local

Interface

communications are established, typically for configuration software running on a PC.

 

 

Orifice meter

A meter that records the flow rate of gas through a pipeline. The flow rate is calculated

 

 

 

from the pressure differential created by the fluid passing through an orifice of a particular

 

size and other parameters.

 

 

P, Q

 

 

 

Parameter

A property of a point that typically can be configured or set. For example, the Point Tag

 

 

 

ID is a parameter of an Analog Input point. Parameters are normally edited by using

 

 

 

configuration software running on a PC.

 

 

PC

Personal Computer.

 

 

Pf

Flowing pressure.

 

 

 

 

 

 

Issued Mar-06

Glossary

A-5

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Emerson ROC827 MAC Address, Manual mode, Modbus, Msec, Off-line, Ohms, On-line, Opcode, Operator, Interface, Orifice meter