Eaton Smart Grid solutions for Ring Main Units

Remote Terminal Unit

(RTU)

The Remote Terminal Unit is a device for acquiring,processing, storing and transmitting information

Measurement and control on the medium voltage (MV) andtransformer side of a Ring Main Unit (RMU) will reduce the outagetime and the possibility of outages. In more advanced applicationswith directional fault indicators and some logic, outages can besolved within seconds after a fault has occurred. After an anomalyhas been detected, the RMU will automatically contact theoperating center where the information is shown on a SCADAsystem and where actions can be taken to solve or preventproblems.

An RTU can also measure Current and Voltage at the low voltage(LV) side of the RMU. By comparing these figures with theinformation from smart meters, deviations can be detected easilywhich indicates either a fault or an illegal power tap.

Benefits of using RTU for Utilities

Nowadays, utility companies are mainly looking for automatedmedium voltage solutions due to the focus of these two goals:

• Improve standard IEEE reliability indices:n SAIDI: System Average Interruption Duration Index (SAIDI)n SAIFI: System Average Interruption Frequency Index (SAIFI)

• Overview of the grid (Voltage, Current, Direction, otherparameters, etc.)

Functionality with an RTU

• Control and status monitoring up to 5 panels

• Alarming, event recording and data logging

• Programmable logic according to IEC 61131-3

• Communication (Ethernet and Wireless)

• IEC 61850 compliancy

• Web interface (monitoring)

Eaton developed this Remote Terminal Unit (RTU)

especially focusing on Ring Main Units applications

for the medium voltage grid.

The RTU enables utilities to reduce the duration of poweroutages. This reduces the downtime in three ways:

• Customers do not have to report an outage by phoneanymore

• Service Engineers do not have to drive to the transformersubstation

• A diagnosis can be made more efficiently

Types Description

RTU Remote Terminal Unit without modemRTU-M Remote Terminal Unit with modem

Operating voltage 24 Vdc +/- 20%Operating temperature -25 .. + 70ºCMedium voltage environment IEC 62271-1 and IEC 61271-304 compliantExternal storage memory Secure DigitalDigital IN 24Digital OUT 8Soft PLC Programmable logic according to IEC 61131-3Web server Web server and web pages availableSecurity Firewall and VPN clientExtension interface Add in additional digital I/O modules

Add in additional analogue I/O modulesReliability High reliability

DIN-rail mountedPluggable connectors for I/O195 x 90 x 60 mm

Communication connections 2x RS-4852x EthernetRS-232 for GPS time synchronisation

GPRS modem Optional and suitable for the protocols IEC 60870-5-104, HTTP(S), NTP and Modbus TCP/IP.

Environmental Standard

Cold, IEC 60068-2-1Dry heat, IEC 60068-2-2Damp heat, steady state, IEC 60068-2-78Cyclic humidity, IEC 60068-2-30Vibration response, IEC 60255-21-1Shock and Bump, IEC 68255-21-2Ageing, IEC 62271-304

Electromagnetic Compatibility Standards

Electrostatic discharges, IEC 61000-4-2Radiated electromagnetic field disturbance, IEC 61000-4-3Fast transient, IEC 61000-4-4Surge, IEC 61000-4-5Conducted radio frequency interference, IEC 61000-4-6Power frequency magnetic field, IEC 61000-4-8Ripple on DC input power port immunity, IEC 61000-4-17Damped ring waves, IEC 61000-4-18Voltage dips, short interruption and Voltage variations on DC input power ports, IEC 61000-4-29Dielectric test, IEC 61180-1Radiated emissions modem, ETSI 301 489Radiated emission, CISPR11, EN55011Conducted emission, CISPR11, EN55022

Communication protocols Ethernet GPRS RS485 RS232

Standard protocols

IEC 60870-5-104 slave • •IEC 60870-5-101 slave •HTTP/HTTPS • •NTP • •Modbus TCP/IP master/slave • •Modbus RTU master/slave •Suitable for

IEC 61850 • •DNP3 • •FTP • •SNMP • •IEC 60870-5-103 •GPS time synch - NMEA •

Eaton RTU General Specifications

Eaton Industries (Netherlands) B.V.P.O. Box 237550 AA HengeloThe Netherlands

Tel.: +31 (0)74 - 246 40 10Fax: +31 (0)74 - 246 40 25info.electric@eaton.comwww.eatonelectric.com

© 2012 Eaton CorporationAll rights reserved.

Form No. SA02200001U-v2May 2012

Medium voltage system application

MV Transformer

SCADA

Ring Main Unit

Operating Center

RTUSmart Platform

LV

Power supply

Batteries

Modem

GPS time sync.