How to make generator(GENSET) ON/OFF using a contactor?

[bikashh]

Dear friends,
I am doing a project in which i need to make the GEN SET on/off using microcontroller.
for this purpose I've chosen to use the emergency button to make the same ON or OFF.Here i want to replace the emergency button with a contactor which will carry heavy current through it and also i'll be able to make it ON/OFF using microcontroller.But the contactor can be energized using a 12/24V DC which i don't have.Can anybody have any alternate solution for this.

Thanks in advance

 

[cameo_2007]

There are contactors with coil Voltages of 230V AC

 

[bikashh]

can you give me some details about the contactor you have mentioned

thanks for the reply

 

[cameo_2007]

there is nothing much detail in that.

Choose your contactor rating. I mean the heavy current rating what you want.

and look for that in the manufacturer catalogue. They will have the contactor for that current rating with both DC coil as well as AC coil.

What is your voltage and current you want to switch and is it single phase or 3phase?

 

[kabiru]

You can follow this link for more info about the contactors,i buid something similar to it but in my own case i use a time delay circute when ever there is failure of mains supply the generator start after 30sec and if the power is restored back it of the generator.You can also follow this link for your contactors.dccontactors.com/Contactors_and_Kits.html

 

[bikashh]

As i said i want to use the emergency button to control the GENSET. Alternatively, can i use a DC contactor between the battery and the starter to do the same job.
thanks for the reply

 

[cameo_2007]

As i said i want to use the emergency button to control the GENSET. Alternatively, can i use a DC contactor between the battery and the starter to do the same job.
thanks for the reply

could you please make it clear once again..

 

[bikashh]

I've two option
first-> to replace the emergency switch and place a AC contactor
here i can turn off the GENSET anytine.
second->to cutoff the battery supply to starter(in GENSET) using a DC contactor
here i can make sure the GENSET will not run in the next ON

Both the contactors are controllable from microcontroller

According to you which one would be better and how should i implement this.

thanks for the reply

 

[cameo_2007]

It depends on your requirement. If you want to make the GEN off in emergency conditions then you need to cut off the line to Generator itself.
Whereas as you said, if it ok the Generator turns off only during the next cycle, probably disconnecting the starter would do.

What is the current rating you would need in case you cuts off the Generator. ?
Dont worry about the coil. The contactors are available in AC and DC coils.

 

[chuckey]

If you bypass the emergency off switch with a contactor contact set, you are defeating its safety function. These switches are normally closed for run, so an additional contact in series that opens to stop the generator is OK, there are already some for over temp, low oil etc. However to start it you must use the proper switching sequence.
Frank

 

[bikashh]

If you want to make the GEN off in emergency conditions then you need to cut off the line to Generator itself.

Dear friend can you please explain how can i do this.

thanks for the reply

---------- Post added at 07:23 ---------- Previous post was at 06:46 ----------

Can i disconnect the supply to the ignition key.I think this will do.

thanks

---------- Post added at 07:37 ---------- Previous post was at 07:23 ----------

m sure the supply to ignition key is DC and is below 24V