Automatic transfer switch for generator, in this project you will learn about mostly used circuit of automatic transfer switch for small power generators. There are many automatic transfer switches are available in market. Some of them are expensive and some are cheap. The reason behind their price difference is type of technology used. There are two kind of Automatic transfer switches are available in market. Analog electronics based automatic transfer switch and digital electronics based automatic transfer switches. Analog electronics based transfer switches use analog electronics in their circuit like operational amplifier , comparators, transistors, diodes and mechanical relays etc. But there is no digital display in analog electronics based transfer switches. Digital automatic transfer switches are most commonly used now a days. Because it use liquid crystal digital display to show values of current and voltage to user. It also shows the status of AC main power and generator to show which power source is currently being feed to load. You can use as many functionalities as you want. Some examples are given below :
- Over voltage and over current protection
- Battery status or amount of battery charging available
- protection alarm and many others.
In this project, I will discuss digital automatic transfer switch and give you brief idea about its circuit diagram and programming. I will discuss following things?
- what is automatic transfer switch for generator?
- main components used in automatic transfer switch.
- circuit diagram of automatic transfer switch.
- how to write code for automatic transfer switch?
What is automatic transfer switches?
As it name suggest, automatic transfer switch is used to transfer from one state to another. In electrical terms , it is used to transfer load from one power source to another power source. Although it have many applications, but in this project, we are using automatic transfer switch to transfer load between AC main power and generator in case of failure of either power source. Automatic transfer switches for generator is used to turn on generator automatically in case of non availability of main power source. it is also used to transfer load to generator after generator transient period. Block diagram of automatic transfer switch is given below :
Above block diagram is self explanatory, but if you still do not feel comfortable let me know with your comments.
main components used in Automatic transfer switches :
Automatic transfer switch use following major components which are used to control the main function of ATS.
- AC voltage measurement of main AC power supply from wapda and out put of generator A, it is used to sense either AC supply from wapda is availble or not. You should have a knowledge about alternating voltage measurement with the help of microcontroller. If you don’t know how to measure AC voltage using microcontroller, check following article :
- Microcontroller : it is used to measure AC voltages of AC main power from wapda and generator. It is used to take necessary actions against availability or non availability of either source. It is also used to display digital values of voltage and current on liquid crystal display.
- Liiquid crystal display is used for digital display of current and voltage values. it is also used to show status of both sources.
- Relays are used to transfer from one source to another based on actions performed by microcontroller subjected to availability of sources.
circuit diagram of automatic transfer switch of generator :
Circuit diagram of ATS using pic microcontroller is shown below. I have used pic microcontroller to measure voltage and to take necessary actions on relays.
[button-green url=”http://store.microcontrollerslab.com/product/automatic-transfer-switch-for-generator/” target=”_self” position=”center”]click here to buy code and circuit diagram in proteus [/button-green]
I will post separate article on working of above circuit diagram and how to write code for this project. keep visiting our website to know more about this project. thanks 🙂
45 thoughts on “Automatic transfer switch for generator”
Thank for this good post.
Could you please give a little explanation about the variable resistors connected to the PIC and about the role of the third relay because I think that two relays are sufficient to switch between the AC power and the generator, aren’t they?
I think that the role of the third relay is to connect the load to the generator after the stabilisation delay, is that correct?
how far did you get with the articles and has this circuit been built and tested
yes it is tested circuit
i downloaded the circuit diagram from your link and get a .DSN file which i am struggling to open
can you tell me what software i need to open the file
circuit diagram is design in proteus
i have opened the file in proteus
when is press simulate i get the following errors
no modules J1 – J3
when i press the button in the schematic nothing happens
can you tell me what i am doing wrong as proteus is new to me i am used to using Diptrace
it is schematic diagram of ATS. You can purchase the code from shop
Please send the complete code and circuit to me…. [email protected]
Please I need information and a circuit diagram for Automatic changeover switch with wireless generator control abilities or mechanism.
The generator rating is going to be between 2.2kva up to 2.5kva, and must be an automatic embedded systems generator on its own not the manual gen set.. Single phase generator and the Mains will be single phase too.. Ie 220volts 50hz…..
The system will be designed to select between two available source of power Givin preference or priority to one out of the two sources of power.
In this case, the selection is between public supply Mains and generator.
The ATS should monitor the Mains supply and check for complete failure or power outage upon which it changes the load over to the generator supply, sends command to the generator wirelessly to start ie ON.. And when the public supply is restored the ATS detects this sends an OFF command to the generator wirelessly to shut down.
check your email
please can u send me the complete code and schematic diagram or circuit drawing my email is [email protected]
contact me at [email protected]
tank you very much i have got so money knowledge about different projects but i am electrical power engineering instructer , so i want to do some projects on my specialization. please help me if you have project related to my specialization.
Pleas I’m working on Automatic change-over switch with fuel level detector,using micro controller. could you please guide me on how the micro-controller works in the circuit.
you can avail my project service by contacting me at [email protected]
Thank you for this idea Mr Bilal Malik
Dear Bilal Malik,
I am working on “GSM based backup generator monitoring using pic16877A and SIM300” including
* Fualt detection (Commercial power failure, breaker trip etc.
*Generator status (Auto, manual, running…
*Fuel level, running hours…
THANK YOU FOR ALL OF YOUR CONSIDERATION !!!
contact me at [email protected] if you need my project assistance
plz bilal snd me ats code on pic control;er
on this id\
thank you for your effort
We want you program
Plz send me Code & circuit diagram :
I need ATS circuitdiagram ATS in proteus with complete cote working in proteus,
may u send me for practice,
I m 70 ears old and jobless so i sit in home and passing time without any business
ABdul Majeed Tahir
Hola señor bilal soy nuevo en el forum me gustaría si usted puede mandarme el diagrama completo del diagrama de circuito de interruptor de transferencia automática del generador o en que pagina lo puedo descargar porque en el sitio donde esta publicado no se ve bien el diagrama del circuito .. ATT Cesar serrano.
Mr. Bilal could you guide me how are you cutting off generator ignition? or pls guide me about its mechanism.
through relay and microcontroller signal
From where are you sensing microcontroller signal and could you tell me about three relay what they are doing?
Please send me microcontroller code at [email protected].
Oh you mean relay cuts ignition when generator turns on? am i right?
by sensing main power supply and code is not free of cost.
Ok…will It sense when generator stables at 220v or will sense at low voltage?
these features can be included
You mean when generator produces excat 220v then microcontroller will sense and during generator stablization ignition continously turns on. so the output: flywheel tooth will be spoil.
please tell me code price.
please i need the code
HI MY BOSS, I REALLY APPRECIATE YOUR POSTING MAY GOD CONTINUE TO OPEN WAY FOR YOU AND KNOWLEDGE.
Bhai how can i get the code and remaining explaination?
Please send me the circuit diagram and code on this email
ok! I am final year of last graduating electrical power engineering . I want to do the project on automatic transfer switch , please send the design and simulation of ATS.
Please help me on design and simulation of automatic transfer switch
thank you for posting this different projects. now I am graduating class of 2018 by electrical power engineering. so I want to do project on ” automatic transfer switch design and simulation ”. for this if you have any source or document on simulation part please send for me . our last presentation will held on February 29/2018 G.C so please please help me by complete simulation of the circuit of automatic transfer switch .
I wait you as you will send within this week on my site [email protected]
Could you please let me know if this system is sending a start and stop pulse to generator or it is just transfering the switch. Can we implement start and stop pulse with a required duration.
I need your help, My email ID is [email protected]
Thank you sir for your help…
Would you please send me schmatic and part values.
Hi, thanks for your post. I’m studying electronic and I was finding this kind of project. Can you help me, with the price or how I can get diagram and code.