Case StudyCase Study

Computer ControlledComputer Controlled Radiation Radiation Monitoring SystemMonitoring System

Nuclear Research Center for Agriculture & MedicineNuclear Research Center for Agriculture & Medicine

Atomic Energy Organization of IRANAtomic Energy Organization of IRAN

Prepared by: A.siminfar, A.bahramiPresented By : Abbas Bahrami

Health physics officer & Network Administratorbahrami@nrcam.org

ALARAALARA

• Radiation protection is an important Radiation protection is an important rule in practices that involve rule in practices that involve radioactive sources.radioactive sources.

• For reducing the absorbed dose of For reducing the absorbed dose of personnel, the working areas must be personnel, the working areas must be under control.under control.

• For this, the health physics officer must For this, the health physics officer must be able to be able to monitoringmonitoring all hot areas. all hot areas.

RequirementsRequirements

– Single area radiation Monitor (stand Single area radiation Monitor (stand alone)alone)

– Area radiation monitoring SystemArea radiation monitoring System

• Single Area Radiation MonitorSingle Area Radiation Monitor

Measures the environment dose rate around the Measures the environment dose rate around the detectordetector

Displays the measured value on a display boardDisplays the measured value on a display board

More sensitive than other dose monitors (e.g. More sensitive than other dose monitors (e.g. Personal dosimetersPersonal dosimeters

• Area Radiation Monitoring SystemArea Radiation Monitoring System

Consists of several single area radiation Consists of several single area radiation monitors, that is controlled through a central monitors, that is controlled through a central unitunit

Communication between monitors and central Communication between monitors and central unit is carried out by a networkunit is carried out by a network

Measured values on monitors are displayed in Measured values on monitors are displayed in central unit (on line)central unit (on line)

Data is stored in central unit for further usesData is stored in central unit for further uses

Computer Controlled Area Monitoring Computer Controlled Area Monitoring SystemSystem

• 1- Area radiation monitors (called as terminals)1- Area radiation monitors (called as terminals)

• 2- Central control unit (PC)2- Central control unit (PC)

• 3- Network3- Network

RS485 (Design a network and define a protocol) RS485 (Design a network and define a protocol)

Consist of:

A terminal mounted in waste room

Area radiation monitor (Terminal)Area radiation monitor (Terminal)(Implemented system)(Implemented system)

Two Area Monitors installed in the Hot Cell Laboratory of Cyclotron

1- Normal State LED1- Normal State LED2- Warning LED2- Warning LED3- Alarm LED3- Alarm LED4- Audio Alarm ON LED4- Audio Alarm ON LED5- Audio Alarm OFF LED5- Audio Alarm OFF LED6- Set Alarm ON/OFF6- Set Alarm ON/OFF7- Pulse LED7- Pulse LED8- Setting Display Un 8- Setting Display Un 9- Display Count/Sec 9- Display Count/Sec LEDLED10- Display Dose Rate 10- Display Dose Rate LEDLED11- Display 7_SEGs11- Display 7_SEGs12- CAT5 Connectors12- CAT5 Connectors13- CAT5 Connectors13- CAT5 Connectors14- Fuse14- Fuse15 – Detector Probe15 – Detector Probe

Top View

Front View

Block Diagram of an Area Radiation Monitor

Send line ADM485 is enabled by the Microcontroller for releasing the BUS after sending data

Using ADM485, Microcontroller’s serial data in TTL format is converted to RS 485 format

Connection of Area Radiation Monitor to BUS-RS485

Terminals connected to the central computer via an interface module

Communication between the terminals and interface is carried out by two transmission lines for send & receive, using RS485 standard

Data busInterface

Digital I/O

Copmputer

Main Software

Terminal 1 Terminal 16

Keyboard

Monitor

. . . .

Interface

Terminal 1 Terminal nTerminal 2

2

2

. . . .

Send

Receive

Software of Area Monitors (Terminals)Software of Area Monitors (Terminals)

Has been Designed for 8051ED2 Microcontroller by assembly language

Has been designed for :

• Count and Process the output pulses of the detector

• Calculate the dose rate regarding to pulse rate

• Display the dose and count rates

• Alarm in high dose

• Communication with the Interface

• communication with user by some micro-switches and display board

Central Control UnitCentral Control Unit

• Designed By VC++, so it is object orientedDesigned By VC++, so it is object oriented

• Can be run with WindowsCan be run with Windows

• is user friendlyis user friendly

• Has following duties:Has following duties:• Communicate with terminals via interfaceCommunicate with terminals via interface• Show the dose rate of terminals On lineShow the dose rate of terminals On line• Save the data in DB ( Save the data in DB ( *.mdb Access format*.mdb Access format))• Show off line data in daily, monthly and yearly Show off line data in daily, monthly and yearly

graphsgraphs• Make ReportsMake Reports• Adjust Alarm level of terminalsAdjust Alarm level of terminals

Main Page of Radiation Monitoring System’s Software

Page2 of Main PagesPage2 of Main Pages

Monitoring of off line dataMonitoring of off line data

Monitoring of Off Line data by GraphMonitoring of Off Line data by Graph

Setting the Alarm Level of TerminalsSetting the Alarm Level of Terminals

Setting the Alarm & Warning Level of a TerminalSetting the Alarm & Warning Level of a Terminal

Networking of The SystemNetworking of The System

Using RS485 StandardUsing RS485 Standard

Terminals is connected to the central computer via an interface module

The communication between the terminals and interface is carried out by two transmission lines for send & receive, using RS485 standard

Interface module controls the network and acts as a BUS master

RS485 StandardRS485 Standard

Interface

Terminal 1 Terminal nTerminal 2

2

2

. . . .

Send

Receive

AdvantagesAdvantages

Simple and low cost hardwareSimple and low cost hardware

(no Hub, switch and Ethernet card are needed )(no Hub, switch and Ethernet card are needed )

Distance between terminal and central control can be Distance between terminal and central control can be increased increased (up to 5 Km)(up to 5 Km)

Possibility of saving data in the interface when the computer Possibility of saving data in the interface when the computer is offis off

RS485 StandardRS485 Standard

DisadvantageDisadvantagessNeed to design and apply a suitable protocolNeed to design and apply a suitable protocol

A hanged terminal may occupy the BUSA hanged terminal may occupy the BUS

(in the end of communication between a terminal and Interface, (in the end of communication between a terminal and Interface, terminal must release the BUS)terminal must release the BUS)

A central computer is required for connecting to A central computer is required for connecting to the terminalsthe terminals

((terminals can not be connected to Ethernet directly)terminals can not be connected to Ethernet directly)

In Existence of LAN, another cabling is need for In Existence of LAN, another cabling is need for this systemthis system

An interface module for connecting the BUS to An interface module for connecting the BUS to computer is required computer is required

RS485 StandardRS485 Standard

Development for futureDevelopment for future

• IP-Based (in progress)IP-Based (in progress)

• Web Based Monitoring (Connecting Monitors directly to Web Based Monitoring (Connecting Monitors directly to InternetInternet))

• Using serial to TCP/IP converter (Network Using serial to TCP/IP converter (Network Enabler for Serial Device), monitors are connected Enabler for Serial Device), monitors are connected to LAN and controlled by a central computerto LAN and controlled by a central computer

• Without considering converter, each terminal is Without considering converter, each terminal is the same as the last one.the same as the last one.

• An IP address is assigned to each terminal’s An IP address is assigned to each terminal’s converterconverter

• Data is sent in the format of TCP/IP from central Data is sent in the format of TCP/IP from central computer, the converter extracts the pure data computer, the converter extracts the pure data and pass it to the terminal’s microcontrollerand pass it to the terminal’s microcontroller

IP Based Area Radiation Monitoring SystemIP Based Area Radiation Monitoring System

IP Based Area Radiation Monitoring SystemIP Based Area Radiation Monitoring System

Ethernet

• Add a Network enabler device (Serial To TCP/IP Converter) in Add a Network enabler device (Serial To TCP/IP Converter) in each terminal instead of TTL to RS485 convertereach terminal instead of TTL to RS485 converter

• No need to an Interface moduleNo need to an Interface module

• Use HUB/switches in networkUse HUB/switches in network

• Ethernet card in control computerEthernet card in control computer

Hardware modificationHardware modification

Hardware modification in the IP-Based Hardware modification in the IP-Based System regarding to RS485:System regarding to RS485:

IP Based SystemIP Based System

• In the Terminal software:In the Terminal software:

Network Enabler (Converter) in each terminal causes:Network Enabler (Converter) in each terminal causes:

• A terminal receive only its own dataA terminal receive only its own data

• A terminal send data without any request - data A terminal send data without any request - data collision do not happencollision do not happen

• In the Central Computer Software:In the Central Computer Software:

Connecting to the Network Enabler Devices instead of Connecting to the Network Enabler Devices instead of interface that was carried out by serial port in the last oneinterface that was carried out by serial port in the last one

Software modificationSoftware modification

Software modification in the IP-Based Software modification in the IP-Based System regarding to RS485:System regarding to RS485:

IP Based SystemIP Based System

AdvantagesAdvantages

• In Existence of LAN, no extra cabling is neededIn Existence of LAN, no extra cabling is needed

• TCP/IP is the transmission protocol, no new protocol in TCP/IP is the transmission protocol, no new protocol in neededneeded

• High reliability of the networkHigh reliability of the network

IP Based IP Based SystemSystem

DisadvantagesDisadvantages

• HUBs/Switches is needed for networkingHUBs/Switches is needed for networking

• Network Enablers for Serial Device is NeededNetwork Enablers for Serial Device is Needed

• To connect a computer in the LAN directly to a To connect a computer in the LAN directly to a terminal, a software must be installed in the terminal, a software must be installed in the computercomputer

• Terminals can not be directly connected to Terminals can not be directly connected to internetinternet

IP Based SystemIP Based System

Web Based Monitoring System

Web pages must be designed in terminals

Terminals must support TCP/IP protocol

AdvantagesAdvantages

• From all over the world each terminal can be From all over the world each terminal can be accessed via internetaccessed via internet

• Central computer can be anywhere Central computer can be anywhere

• Protocol and network hardware are standardProtocol and network hardware are standard

Web Based SystemWeb Based System

Thank youThank you