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Starting an automated backup generator project


Backup generators seem to be quite a lot more expensive than they need to be. I'm about to start working on a project involving a few contactors, an arduino with some relay cards and a raspberry pi to make a backup generator system that can be wired into any generator you want. I'll keep you posted (and it probably wont be moving along too fast as I've been tasked to do this in my free time). I want to post all of the plans and code up here afterwards for all to see and use!





Seems like  good idea. Do you mean to make the generator more "smart" so it's got the same features as those overpriced fancy one's?



Interesting. How about remote controlled as long as there is a ups in line?



Thats the idea. The arduino will do all the motor control and circuit switching, and the Pi will do things like email reports for power outages, length of time, generator run time, load etc. (Much of the data for that will be sent over serial connection from the arduino, but I was just going to run an apache server on the Pi to give you a web access point to look at reports from)

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Do it, you should document what you did so others can see and learn from it too.



I plan on it (though thats usually something I fall woefully behind on) got the go ahead from my boss. Going to be buying a little pile of parts soon. 

The list so far consists of:

-one arduino uno (just for starters)

-one raspberry pi (cause he'll pay for it and I want one to play with)

-2 60a contactors(one for each 120v lead, I will be doing the entire office)

-1 arduino relay board (4 relay)

-1 24v ac transformer(for activating contactors)

The power will get cut off from the pole power, then the generator will be started, and the power cut back on. This will keep from having the messy power that occurs from 0-3600 rpm. The 2 relays and 24v transformer are to activate contactors. the other two are for the ignition and starter on the generator.

The Pi will send email alerts and keep updates available on a screen that will be mounted on the outside of the breaker box for realtime info. I'll let you know when i start building.

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here's some ideas: add an ups after your generator, so you get a seamless power, also an on-line one is better, in case the generator messes it up
you could also add a gas level monitor, and something to identify if the motor is running, that alerts you in case it didn't start, so you can start it manually

this interests me, because I thought about it 2 days ago



I'm not sure if you looked into generator costs (and batery bank for switching over), but a 4kVA generator is pretty quickly gonna cost around 400$, plus the cost for an UPS that can bridge the gap between power loss and generator startup.

If you are planning to do big setups I'm guessing price will be around 100-200$ per computer that needs to be powered (at 400 watt per computer), and the gas bill will probably be pretty insane as well.



Any updates on this? i’m looking to do exactly this.

I have a UPS on all the important devices



use the arduino relay board to control ice cube relays ( with the proper diodes to prevent debounce) and the ice cubes to control the contactors
solid state relays while low power consumption and mechanically isolated tend to intermittently contact if static electricity is high enough to switch the opto coupled circuit in the relay, and the latent time the ice-cubes take to close a contact can overcome nuisance firing from the ssr. and they can also negate ghost voltages.
your arduino can also monitor the temperature of the generator with the proper thermo-couple but its just makes for a more complex program to write.

I designed and did a lot of industrial automation before i retired so we had to cover a lot of bases (a whole lot of fun to get old machinery and newer computer systems to work together)