faqs and overview on scada, telemetry and telecontrol using tetra-infrastructure

FAQs and Overview onSCADA, Telemetry and Telecontrol

using TETRA-Infrastructure

Funk-Electronic Piciorgros GmbHMichael D. Piciorgros (CEO)

Piciorgros GmbH * Germany

Why TETRA and not ….

APCO 25

DMR

WiMAX

WiFi

GSM, Edge, 2G, 3G, (4G)

Other digital Wireless Systems


… because ?

Try to compare all technical and commercial aspects of the following presentation with the

mentioned technologies


SCADA (Supervise Control and Data Acquisition)

The term “SCADA” basically includes the whole system starting from the Monitors and Computers in the Control Room, the Interfacing to the Infrastructure, the Infrastructure itself, up to the Outstations the PLC’c and Sensors or Actors.

This presentation will show how the SCADA Control Room Part can be interfaced to TETRA Infrastructure using different options and how the data communication can be optimized.

Ref.:

http://de.wikipedia.org/wiki/Supervisory_Control_and_Data_Acquisition


Ref:Scada: WikipediaMonitor: Samsung

Typical SCADA Server Layout


What can TETRA provide for Supervise Control and Data Acquisition?

Keywords are:

Status MessageSDS Messaging

Secondary Control ChannelPacket Switched DataMulti Slot Packet Data


STATUS Message:

A Status message is the shortest and fastest way to send or receive command or status information over TETRA

Status Message size is 16 BitCan be sent/received from control room

(SCADA) or from any outstation

STATUS messages can be used for:Alarm Information from outstationsPolling Request “Silence Command” from SCADA


SDS Message:

An SDS message can be compared with a SMS text message in GSM networks but a SDS will be instantly delivered

SDS single message size is up to 254 byteMulti SDS can be used for larger data

SDS messages can be used for:Text communicationData communication (protocols, alarms, . . . )


Secondary Control Channel:

SDS Messages are sent on the MCCH (Main Control CHannel) on the first time slot

Additional control channels (SCCH) can be configured for each of the remaining three time slots

On one carrier a maximum of four control channels is possible

SCCH can be used for:Separate data from MCCH or Voice TrafficReduce MCCH loadSplit applications


Packed Switched Data:

With Packet Data, IP communication is possible on TETRA networks

Packed Data uses Traffic Channels for communication, in the same way as voice communication

TETRA provides Packet Data channel sharing between devices

Packet Data can be used for:UDP communicationTCP communication (!)Any low speed IP application (Data)


Multi Slot Packed Switched Data:

Multi Slot Packet Data uses two up to three traffic channels on the first carrier

Multi Slot Packet Data can use up to four traffic channels on the second carrier

MSPD can be used for:UDP communicationTCP communication (!)Any low speed IP application (Data)


Typical SCADA Applications:


Surface Coal Mining (Water Level Control)


GAS Flow Control with Solar Power


GAS Quality Control


Waste Water Treatment Plant


Utility (Energy Companies)


Network Structures when using TETRA for SCADA applications

Keywords are:

Radio to Radio CommunicationSwMi to Radio Communication

SDSPacket Switched DataMulti Slot Packet Data


SCADA using based Radio-to-Radio

Communication

Control Room

TETRA Switch

AMR

Command and Control Line Device

Serial Communication

TMO-100

TMO-100

TMO-100

SDS

SDS

SDS

SDS

SDS

TMO-100

Serial Interface

Serial Interface

I/O


SCADA with Radio to Radio Communication

Easy to set upNo need to be physically linked to the TETRA

switch (infrastructure)Point to Point and Point to Multi PointLow cost solution

Two RF links to the TETRA infrastructure neededReduced communication speed


SCADA – using an

Control Room

TETRA Switch

AMR


Public Lighting

TGW-100SDS Gateway

Two Serial Interfaces

IP Communication

TMO-100

TMO-100

TMO-100

SDS Gateway

SDS

SDS

SDS

I/O


SCADA using an SDS Gateway

No RF traffic on the control room sideAbout 50% faster than Radio-to-Radio

communication

Needs an SDS Gateway ($$$)Needs to be connected to the TETRA switch


SCADA – using a Gateway

(Serial over IP)

Control Room

TETRA Switch

AMR


TGW-100P Packet Data

Gateway

Two Serial Interfaces

IP Communication

TMO-100

TMO-100

TMO-100

Packet Data

PD

PD

PD

Serial Interface

Serial Interface

I/O


SCADA using a Packet Data Gateway

No TETRA uplink on the control room sideAbout 50% faster than Radio-to-Radio

communicationMCCH is NOT used for data communication

Needs an SDS GatewayNeeds to be connected to the TETRA switch


SCADA – using direct Communication

Control Room

TETRA Switch

AMR


Direct IP Communication

TMO-100

TMO-100

TMO-100

IP

IP

IP

PD

PD

PD

I/O


SCADA using IP Communication

No TETRA uplink on the control room sideAbout 50% faster than Radio-to-Radio

communicationMCCH is NOT used for data communicationNo special SCADA to TETRA gateway needed

Only IP communication possibleNeeds to be connected to the TETRA switch


Some FAQ:


What serial Protocols can be used with TETRA?

Most of the common serial protocols like Modbus, DNP3, Pak Bus, BSAP, ROC, IEC60870-5-101, ... and also others can be used with TETRA.Depending on Radio-to-Radio communication or Switch-to-Radio communication the SCADA Server response timeout should be set to an appropriate value between 2 and 5 seconds.


What IP Protocols can be used with TETRA?

On Radio-to-Radio communication care should be taken when using TCP protocol, but it is no problem to use UDP.


What is “Serial over IP” and when should it be used?

I cases where the TETRA infrastructure does not support Secondary Control Channels (SSCH) and the Main Control Channel (MCCH) should not be overloaded, the serial data can be packed into IP frames of up to 1,5 k Bytes and sent on traffic channels with Packet Data or Multi Slot Packet Data.


What is “Packet Data Channel Sharing”?

Most of the SCADA applications use polling protocols. That means that the SCADA Server (Control Room) sends a request to an outstation asking for process data. And once the outstation device has responded, the next field device will be polled.In case of Packet Data communication, with each polling the specific outstation will switch to the packet data traffic channel and respond to the SCADA Server request.As there is no logical “End of Data” for the TETRA infrastructure, each device will stay after the data communication has been terminated for some additional time until a “Ready Timer” expires.With the Packet Data Channel Sharing, additional devices can use these still occupied channels


How can TETRA be used efficiently for SCADA applications?

For SCADA applications group communication should be avoided because it generates unwanted traffic

Data compression should be used if available Switch to Radio communication gives best performance For Data Applications using a dedicated SCCH avoids the

overload of the Main Control Channel


Can TETRA modems also use the TETRA voice feature?

Yes! Depending on the modem design, voice and data features are available


Please don’t forget:

All of that was:


Funk - Electronic Piciorgros GmbH

Claudiastr. 5

51145 Köln-Porz

Germany

www.piciorgros.com

www.TetraModem.com

Thank you very much for your interest in our Products

faqs and overview on scada, telemetry and telecontrol using tetra-infrastructure

Documents

scadapiciorgros gmbh

switched data

piciorgros ceopiciorgros

control room scada

scada control room

separate data

devicespacket data

solar powerpiciorgros