I need a circuit that start generator automatically when electricity failure. When electricity restore then generator automatic shutdown.

 

Hi ..
In order to stay within the rules of this site RE mains connected equipment I have to advise you that all you need to detect supply fail is a relay, or simmilar, driven from a transformer or other commertial power supply and not to muck about with anything that directly connects to the mains supply.

That said .... if you are controlling a generator detecting a supply fail is not what you need to be concentrating on ...

Engine and starting control will be far, harder if you dont want to break things and then you need to think about how the generator output is connected to your distribution circuits.

It is unlikley you will get advice here with respect to the latter, mostly because it would be very dangerious if you got it wrong, with both fire and electricution being significant risks.

I dont mean any offence but if you dont know how to detect a supply fail you definatly shouldnt be messing with standby generator switching.

I can advise RE engine strating and control, mechanical and electrical, but it wont do you much good without the supply switching interlocks.
Sorry to be blunt but playing with this stuff and getting it wrong will kill your genny for cirtain and might kill you in the process.

Perhaps one of the moderators can advise what scope of advice can be offered without contraviening board rules ....

Al

 

This is a perennial one, the poster from some region where mains supplies are difficult, trying to make up a standby supply or UPS on the cheap, and generally wanting to avoid using purpose-built equipment. Typically if storage elements are required they are to be vehicle batteries, despite their unsuitability for this type of use.

Basically it can't be done, at least not using methods which could be approved of by those in the more developed world. Giving you half-baked advice could put us in a lot of trouble, as well as exposing you and others to potential danger.

 

One thing you must be aware of is shutting down the connection to the main(from the power company) power when running a generator in the house. You could without meaning too kill someone trying to restore the power.