[LEDE-DEV] solar wifi AP designs

[Daniel Golle]

Hi!

I use EPSolar Tracer MPPT controllers here, the older RN series got a
3.3V-level TTL serial port for which I've written a small tool which
allows easy integration with collectd:

https://github.com/dangowrt/tracertools/
(package can be found on github.com/openwrt/packages as well)

The slightly newer BN series is different because it got an RS-485 port
and speaks proper Modbus, ie. you can use collectd-mod-modbus to query
the controller and won't need any specific tools (but an RS-485
tansceiver and a proper UART with RTS/CTS signals to drive it -- I
didn't find any USB-to-serial solutions which are as realiable as an
in-SoC UART and won't randomly stop working after a couple of weeks)

collectd.conf for 'true' Modbus capable 'BN' series controllers:

https://pastebin.com/tzGWi5tX

The BN series is also nicer because you can attach more power than
the controller can take, so eg. have up to 350Wp connected to a 10A
controller and still be fine in winter without burning the MPPT in
summer...

A screenshot taken from a slightly larger system:

http://picpaste.com/solar-fSkWIMVQ.png


I admit that a 10A+ controller with a pricetag starting around EUR 70
is too much to just drop it with a small panel somewhere on a tree to
power a single router -- for those cases I've sometimes used TP-LINK
MR2030 with a 5V USB powerbank and simple step-down converter to charge
it directly form a solar panel (obviously without MPPT nor monitoring).
It will be fine in the summer, it won't survive the long nights in
winter (also because those crappy batteries don't like extreme
temperaturs). So I look forward to see a nice and small solution for
5A Elektra is currently working on. And I'd love to see it charing
lithium batteries recycled form old laptops rather than lead-acid....

Watch her talk about that:

https://www.youtube.com/watch?v=NLP4MxQp8kk



Cheers


Daniel



On Sat, Jun 10, 2017 at 01:01:00PM +0000, Vieno Foo wrote:
> At the local hackspace we changed some WRT54GL to do PoE. Power the WRT
> via a 12 V battery and have the same voltage on the output. Input
> voltage = output voltage.
> The battery could be replaced by a solar panel or a combination of both. ;-)
> 
> http://picpaste.com/IMG_20170605_064049.jpg
> 
> kind regards
> txt.file
> 
> Eric Luehrsen:
> > On 06/04/2017 08:46 PM, Dave Taht wrote:
> >> I keep finding nicely integrated solar/battery/camera designs like these
> >>
> >> https://www.amazon.com/s/ref=nb_sb_noss_2?url=search-alias%3Delectronics&field-keywords=solar+wifi&rh=n%3A172282%2Ck%3Asolar+wifi
> >>
> >> But what I'd like is just something with solar and battery that could
> >> function as an AP, that was well supported by lede. Ideas?
> >>
> > A router that runs on a 12V supply
> > 
> > - 
> > https://www.amazon.com/TP-Link-Archer-C7-Wireless-Gigabit/dp/B00BUSDVBQ/ref=sr_1_2?ie=UTF8&qid=1496629045&sr=8-2&keywords=tp+link+archer+c7
> > 
> > Good old fashioned lead acid battery
> > 
> > - 
> > https://www.amazon.com/Interstate-Batteries-SLA1116-Lead-Battery/dp/B004KNPIWS/ref=sr_1_4?ie=UTF8&qid=1496628899&sr=8-4&keywords=Interstate+Batteries
> > 
> > 12V Solar Panel
> > 
> > - 
> > http://www.homedepot.com/p/Nature-Power-22-Watt-Amorphous-Solar-Panel-Charging-Kit-with-8-Amp-Charge-Controller-for-12-Volt-Systems-42022/300854090?MERCH=REC-_-PIPHorizontal1_rr-_-204759893-_-300854090-_-N
> > 
> > Duct Tape :-)
> > 
> > - 
> > http://www.homedepot.com/p/NATIONAL-1-89-in-x-40-yd-Utility-Grade-Duct-Tape-Silver-1118105/202352331
> > 
> > _______________________________________________
> > Lede-dev mailing list
> > Lede-dev at lists.infradead.org
> > http://lists.infradead.org/mailman/listinfo/lede-dev
> > 
> 




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