[Commotion-discuss] Remote site, solar-battery data logger.

[Andy Gunn]

Hi Jared - just to follow up on Dan's message, I think you will probably
have to use a few products to accomplish this task, or plan on spending
quite a bit for a higher-end charge controller.

Just a note: I'm not a solar expert, but I did do a stint as an
electrician, working on solar installations along with the usual
residential stuff. I am more of an expert on remote monitoring,
instrumentation and control from my time working in radio, where remote
control of distant transmitter sites is a must.

That said, I was able to find a charge controller from a company I have
actually heard of that has Ethernet access and some semblance of control
over the web. Note: I have not used this controller before, so I can't
speak to it's features:
http://www.midnitesolar.com/productPhoto.php?product_ID=331&productCatName=Charge%20Controllers%20-%20Classics&productCat_ID=21&sortOrder=5&act=p

Obviously, it's not cheap, so that doesn't fit your low cost need. My
suggestion is to use an off-the-shelf charge controller, and combine it
with a remote monitoring sensor or remote control unit that you can
program to monitor voltages, temperatures and use internal relays to
reboot or disconnect equipment.

Some examples of lower cost PWM charge controllers are here:
http://www.solar-electric.com/stpwmchco.html
(Though PWM are not the most efficient charge controllers, they are
lower cost)

A company called Control By Web has a series of very good remote control
units with web interfaces:
http://www.controlbyweb.com/products.html

While they are not exactly cheap, they are robust and some have multiple
features. They are also small, DIN rail mountable, and low power. My
recommendation is the X-320, though it might be overkill:
http://www.controlbyweb.com/x320/

If you have more time on yours hands, something like an Arduino or
Raspberry Pi can be set up to take in voltages or sensor data on the
analog inputs, control external relays, and is fully programmable. I'm
not an expert with those, so I am only speculating, but I think would be
able to serve your purpose very well.

Sorry I don't have a magic bullet, but I'm hoping someone out there is
working on one!
-A


On 05/13/2014 09:54 AM, Dan Staples wrote:
> That sounds like a tall order :)
> 
> I've had little experience with solar powered tech, but from what I have
> worked with and seen, there isn't any sort of all-in-one package like
> the kind of thing you describe. Folks I've seen that have rigged up
> solar panels and batteries to routers and the like have had pretty DIY
> setups.
> 
> One person who I would suggest talking to is Danny Iland
> (http://www.dannyiland.com/). He does solar-powered wifi router stuff,
> which he demoed at last year's Int'l Summit for Community Wireless Networks.
> 
> -Dan
> 
> On 05/08/2014 01:23 AM, Jared Hoy wrote:
>> I'm thinking about setting up some high vantage point routers that are
>> operated by a solar panel and some small SLA or lithium batteries. I
>> have been looking around for low cost solar chargers that incorporate
>> "smart charging" capabilities combined with data logging and
>> network-ability. 
>>
>> Does anyone know of any small, low cost, weatherproof solar chargers
>> that can charge a single sealed lead acid battery, lithium ion, or
>> similar battery? Something that also incorporates a small data logging
>> memory that can be accessed and visualized remotely over a network
>> connection? Something that is HTML so it can be viewed in a webpage on
>> any platform? Maybe even email alerts to alert when the system requires
>> maintenance?
>>
>> Like I said, the routers would be located in difficult to reach and
>> remote locations and should be stand alone and off the grid. I need a
>> way to keep an eye on the system without being physically present unless
>> absolutely necessary. Ideally the only malfunction that should occur
>> would be a failing battery and would need to be continuously monitored
>> for the continued safety and security of the community.
>>
>> I'd like to avoid building my own chargers unless there is no
>> commercially viable and inexpensive solution.
>>
>> Any comments, thoughts, suggestions?
>>
>> thanks,
>> Jared

-- 
Andy Gunn, Field Engineer
Open Technology Institute, New America Foundation
andygunn at opentechinstitute.org | 202-596-3484