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Glossary of Terms M to Z

Terms and abbreviations used throughout this website are briefly explained on this page. Click a link to find a short description of that term.

 
MCC
Modbus
MPM
OSM

Recloser
Rogowski Sensor
RTU
SCADA
SEF
SF6
Telus
   

MCC - Motor Control Centre
A modular cabinet system for powering and controlling motors in a mine or factory.


Modbus
Modbus is a communications protocol used for automation applications. It is often used in SCADA systems especially in substation automation. NOJA Power's range of OSM reclosers are supplied with the Modbus protocol as standard.


MPM - Main Processing Module


OSM - Outdoor Switch Module
The Outdoor Switch Module is an outdoor, pole-mounted, medium voltage recloser. It features full-directional protection, current and voltage measurement on all six bushings, no SF6 or oil insulants and is light weight. Full SCADA and communications features are standard along with programmable digital I/O.


Recloser
A recloser is a circuit breaker incorporating a multishot, autoclosing relay, installed on a medium voltage feeder. They are designed to trip when a fault is detected, then automatically reclose after a set amount of time in an attempt to clear transient faults on the feeder. They can save considerable time when restoring power.
More info - Recloser product page


Rogowski Sensor
A Rogowski sensor is an air-cored CT design made out of a helix coil. They are immune to core saturation at high fault currents, produce safe voltages (millivolts) have an increased accuracy over a wider range and are very lightweight. NOJA Power use Rogowski coils for phase and earth current measurement in the OSM recloser.


RTU - Remote Terminal Unit
Remote control and monitoring unit used in SCADA systems.


SCADA - Supervisory Control And Data Acquisition
SCADA systems are used to monitor and control a population of remote devices from a central control room. A communications protocol is required to receive and transmit alarms and other data. NOJA Power reclosers are SCADA ready with RS485, RS232 ports and protocols such as DNP3 and Modbus.


SEF - Sensitive Earth Fault
Sensitive Earth Fault is a form of Earth Fault protection capable of detecting low fault currents. The OSM recloser can detect SEF from 4 - 80A.


SF6 - Sulfur hexafluoride
Colourless, odourless gas used to insulate electrical switchgear. Identified by the KYOTO protocol as one of the 6 greenhouse gasses. SF6 gas has a an environmental impact 24000 times CO2 (Carbon Dioxide) and has an atmospheric lifetime of up to 3200 years


TELUS
TELUS is a software package that allows easy configuration of an OSM recloser via an RS232 connection. It features a graphical protection curve tool, I/O mapping tool, SCADA protocol configuration and can be used to change every setting inside the control cubicle. TELUS is also used to transfer event data from the recloser to a pc for off-line analysis of faults, load profiles, events and other recorded information.