Hi all,
I am working on building a business doing solar integration, which means I help design and install solar panels for homes and businesses, and I need some assistance with something. I'd like to make a security system for the panels, which I envision will be a bunch of little RFID tags that will send signals to a central receiver, so that if a panel is moved, the receiver can send a text message or a phone call to the client alerting them. I'd like to do this myself, and I have a fair amount of basic knowledge about electronic engineering, but am over my head on how to construct something like this. The design will need to incorporate the fact that the panels may be as much as 50 or 60 feet from the receiver, and (obviously) cost is a factor and I'd like to keep this thing under a few hundred bucks all told. Most installations have 50 panels or less, but they'll each need to have their own RFID tag that actively sends a signal to the receiver, but hopefully at an intermittant rate so as to conserve battery life. I have a microcontroller programmer, an oscilloscope at my disposal if that will help, and an old HP spectrum analyzer that I can use for diagnostics as well. I'd really appreciate any and all help anyone could offer. Thanks in advance!

 

I don't think RFID is going to be the right technology for this, although there is a "long range" that might work. It's not as cheap as regular rfid stuff. Steve Wozniak was once working on a technology to watch a herd of kids, and keep them within a geofence. That'd be great, but it never made it to market. But maybe the technology is out there.

 

Sounds like a great idea. Almost anything could be tagged! Another market might be air conditioner condensors because of the high theft rate (to sell them for their copper content). A $500 machine that phones home when someone moves it is a great idea!

 

So nobody has any ideas on how I might put something along those lines together?

 

I think you'd be better off using the panels' existing electrical connection to decide that something has failed or been removed. For one thing RFID operates over a much shorter range than you've mentioned, and then, the panels are already wired together. Why not just check for continuity or consistent voltage or resistance?

 

I'd do it with xbee modules versus RFID

Of course there are "better" ways to prevent the theft in the first place.. Like simply using "security fasteners" where a special bit is required to unscrew them or tons of other methods that don't involve electronics...

You really need to figure out how they are being stolen and then prevent that.

 

I would love to have an RFID tag reader (low cost) that can get more than a few feet of range!

Anyway, RFID is definitely not the way to go on this, I would go with John P.'s and mcgyvr suggestions, just to keep the cost down, which you can also pass along to your customers..... adding wireless and a bunch of other electronics to the panels will just increase the cost and maintenance on the end users part.

or if you really want to add costs to the products, and go with wireless, check into zigbee and also MiWi...... and there are also some decoders/encoders made by Holtek that are addressable so you could have a whole bunch of transmitters connecting to 1 receiver, you can pair these encoders/decoders with some 433Mhz tranceivers or similar which can be had from here >> http://www.linxtechnologies.com/...... linx also makes GPS modules, just in case you want to integrate that into the panels so they can be tracked... almost like a lojack for solar panels...

 

Thanks guys.. I am all for the low tech solution, so will look into something like that for the installations. I like all the suggestions though, and it's always good to learn more about all things electronic