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Chapter 6

 Interfacing 

Overall automation and SCADA system is developed by interfacing

• PLC and HMI

• PLC wit Arduino !coordinator"

• Arduino wit Switcgear systems

6.1 Interfacing of Switchgear System with Arduino:- 

PLC sends signals to arduino and te coordinator #igbee on tis arduino broadcasts tesesignals$ %e routers at te receiving end& receive te signals and send to arduinos wic respond

accordingly$

Since& arduino operates at '( and to control te operations of switcgear systems )*(

signals are needed$ %o convert te '( signals to )*( level an +,cannel '( interface relay boardis used$ It contains + - '( relays rated at ./A0)'/($ 1ac relay is switced on0off by an opto,

isolated digital input tat can be connected directly to an arduino output pin$

 

Fig 6.1 Schematic Diagram of an Opto-Isoated !eay

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  Opto,isolation assures tat no ig voltage surge travels from te switcgear system to

arduino and ence provides protection to it$

  2outers #igbees on te switcgear systems receive signals and send to arduino to control

different operations of switcgear$ 3or tis& an interfacing panel is developed wic contains

relay board and 4L2 switces !male"$ %is panel is connected to bot arduino and switcgear 

system$ 3or eac switcgear system& eleven connections are re5uired !tree for modes and eigt

for start stop"$ 4L2 connectors are used$ It as tree pins$

3ig 6$) 4L2 Connector on Switcgear System !3emale"

  Pin . is for earten& ) is grounded and pin 7 is connected to be connected to )*($ 8ires

from te relay board wit male switces on one side are used to connect to female switces on

te switcgear systems as sown in 3ig$ 8enever arduino ma9es its output pin low& respective

relay is actuated& connecting :)*( from adopter to pin 7$ ;egative terminal of te adopter is

directly connected to te ground i$e$ pin )$

Same connections are present on eac switcgear systems !eleven on eac"$

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Fig 6." #ard $are Connections from Arduino to !eay

%oard and Switchgear System

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