CUSTOM UPS system

[Daniel Hercules]

I am interested in developing a custom UPS. I have a series of FreeNAS systems but interested in making a device that will send a signal (I need to know what kind of signal FreeNAS accepts) so the FreeNAS will turn off. I am an expert electronics developer and I have a custom made UPS system, but now I have to integrate it with FreeNAS.
I am pretty sure that someone knows if I can plug a microcontroller and make the MCU send a specific ASCII code to the FreeNAS so it shuts down.
Please help. Thanks.

 

[anodos]

I won't comment on the sanity or insanity of this project, but you'll probably want to make it so that it communicates properly with NUT - http://networkupstools.org/

 

[RoboKaren]

I also won't comment on the sanity of this project except to say that UPS devices are now so cheap (I just bought a 1500 VAC for $90) that they're essentially disposable.

Almost all UPS devices now use USB rather than serial. They communicate using the USB HID for power devices: http://www.usb.org/developers/hidpage/pdcv10.pdf

You're best off emulating a device that's already in the driver database of Network UPS Tools since NUT is so widely used. An arduino should do the trick.

But again, once you price out an arduino + batteries + your time, I can't see how to make the equation work in your favor.

 

[joeschmuck]

What is the reason behind building a custom UPS? Is it just a project you can learn from and just want to do it because you can? Or do you have a specific need and a custom unit makes more sense to you?

If you already have an UPS on a computer on your network, you could use that computer (set as MASTER) to signal other systems to shut down, like FreeNAS but it needs to be set to SLAVE. The easy way is to just buy a reasonable UPS that has the connectivity already, but I'm a tinkerer so I couldn't in good faith push that down someone throat.

 

[Ericloewe]

The best option would be to look for a very well-documented format that NUT supports and stick to that. Or you could make a USB UPS-class interface, which should be documented somewhere.

I am an expert electronics developer and I have a custom made UPS system

Care to share some details?

 

[Fox]

I understand the insanity of this project. I'm very unhappy with my two ups's.