Current Cottonpickers experiments

Current stuff I'm playing with...
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cottonpickers
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Re: Current Cottonpickers experiments

Postby cottonpickers » Tue May 21, 2013 7:20 pm

Today I completed a new modification to the solar pi switch. This is to provide an 'Off, Off at Night, On' settings. Perfect for daytime cameras or nightime security devices. Helps save a lot of battery too :-) I've got to change the pi case to let this fit in easier, but for now its a 'by request' option for anyone that would like it. If you've posted on this website before today I can do it as a free upgrade, otherwise its an additional £3 or $5 to add this to your case!


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Re: Current Cottonpickers experiments

Postby cottonpickers » Fri Jun 07, 2013 6:56 am

Well I'm still playing with the 3 way switch and relay to have a solution to switch the pi off at night (or off in the day) - the new switches arrived, which are a little biggeer than I want (only around 2mm but enough that needs me to modify the case to get them to fit - and of course I then have 2 styles of case to work with ;-)

I'm also looking at incorporating a small fan in the 1.5amp USB Project box. this will have a low current draw of around 150ma, and likely I'll limit that further to maybe 20-30ma. I'll have it only come on when its sunny and go off when there's not much sun. I'm not sure whether to place on the side like the pic here, or on the bottom facing down (or give both options) should help keep things a little cooler in hotter whether.

Image

I'm hoping to complete the first 'pilot' of this next week (parts are on order :-)

I've got another 'option' that I'm working on at the moment that I'm quite excited about - but for now I'm keeping quiet about it as the first few attempts haven't worked out. This option is around a month away I guess.

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Re: Current Cottonpickers experiments

Postby cottonpickers » Thu Jun 13, 2013 6:17 pm

No progress on the switch modifications. Fans are due to arrive tomorrow. BUT -whohoo- my Messenger bag arrived today. I fancy putting a solar panel on one of these... so watch this space. If I have time, I'll be trimming the panel tonight and maybe marking out and cutting the hole. This will be a pilot model.

The plan will be to incorporate a 1.1amp panel likely with apple circuitry so that you can charge an apple iPad, or iPhone or one of those battery boxes for later charging. Should keep me busy tonight

Image

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Re: Current Cottonpickers experiments

Postby cottonpickers » Fri Jun 14, 2013 4:08 pm

Well , here's how it turned out!!

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The finish is not perfect, but for a protoype I'm very pleased. It puts out 1100ma (tested today) which is amazing.

What I particularly like is that you can face it normally and the panel is concealed, but simply turn the messenger bag around and you have the power of the sun! - I used it to charge up my iPhone 5 today :-)

If anyone is interested in this Solar Messenger Bag (a truly one of a kind!) let me know - I'll send to anyone in the UK for £49 or if you have posted to this website before this email I'll send it over for £39. Inside the pocket is a USB port that you plug any usb device in to to charge up.

Aikidokajeff
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Re: Current Cottonpickers experiments

Postby Aikidokajeff » Sun Jun 16, 2013 3:55 pm

Hmmm tempting.
Thinking about it...

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Re: Current Cottonpickers experiments

Postby Aikidokajeff » Sun Jun 16, 2013 4:41 pm

Will it be ok if there is no load attached?
As the panel isn't on an internal surface you can't simply close a flap to stop it delivering power. (I know you could turn it over)
Is there a protective cover/film on the panel?

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Re: Current Cottonpickers experiments

Postby cottonpickers » Sun Jun 16, 2013 7:46 pm

Aikidokajeff: Solar is great as you can both leave it without load or short circuit to no ill effect.

This does not have a protective cover (I did think about putting it under the flap but it would have sat lower down and I figured that would not have looked as nice.
Best regards
David

ForestBE
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Re: Current Cottonpickers experiments

Postby ForestBE » Mon Jun 17, 2013 7:52 pm

cottonpickers wrote:Well I'm still playing with the 3 way switch and relay to have a solution to switch the pi off at night (or off in the day) - the new switches arrived, which are a little bigger than I want (only around 2mm but enough that needs me to modify the case to get them to fit - and of course I then have 2 styles of case to work with ;-)
I'm also looking at incorporating a small fan in the 1.5amp USB Project box. this will have a low current draw of around 150ma, and likely I'll limit that further to maybe 20-30ma. I'll have it only come on when its sunny and go off when there's not much sun. I'm not sure whether to place on the side like the pic here, or on the bottom facing down (or give both options) should help keep things a little cooler in hotter whether.
I'm hoping to complete the first 'pilot' of this next week (parts are on order :-)
I've got another 'option' that I'm working on at the moment that I'm quite excited about - but for now I'm keeping quiet about it as the first few attempts haven't worked out. This option is around a month away I guess.


Dear experimenting Cottonpickers,

I am very interested to she how this experiment evolves.
Having read through all these threads here I am not certain now what type of batteries (NiMH or Li) you will be using for the for your 1.5amp USB Project box. I am definitely interested in it (the larger the power storage capacity the better - I am looking for 4 days of reserves for a Pi A with WiFi, i.e. 4x10000 mAh D Cells or your 8 D Cell version).
However, from the pictures I doubt that the casing is really water tight (i.e. leave it out in the forest for the whole year without any water intrusion - the Belgian weather was already quoted here). Thus, your fan idea is interesting, but defeats the purpose of watertight. Maybe use a (partly) metal casing and link heat sinks (heat pipes) to it (like in small computer housings)?
Finally, concerning your switch: this is a must have to allow for a full year's unattended operation (i.e. switch itself off during no sunlight to preserve power - and on again once the sun shines; a 8:00 to 20:00 timer solution would do for my project too).

Thanking you for the inspiring work and staying tuned for your mystery other option,

ForestBE

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Re: Current Cottonpickers experiments

Postby cottonpickers » Tue Jun 18, 2013 6:15 am

ForestBE: Oh I should have been clearer :-) the 1.5amp panel is suited to any 'External USB Battery Pack' - and these are almost always Li-ion. I can offer empty battery packs now (2, 3, 4 or 6 cell models) but I figure most people will go and buy them direct, with batteries already installed. Theres so many to choose from out there that I think most folks will either use one they have already or enjoy picking the one that means their needs (eg some have displays to show remaining voltages, some have massive capacity, some have multiple ports to power other devices etc)

The hole for the lead to go through is barely any bigger than the lead and uses Fish tank sealant (so that hole should be fine) The housing top and bottom overlaps by about an inch - Its not airtight, but there is a good overlap. As the panel is A4 sized there are a lot of boxes out there that would fit this panel perfectly - I'd be happy to look at others. Alternatively once you have a pi set up in the sun you might consider some foam in between the top and bottom cases or even silicone sealant. However , hoping that for most folks its unecessary.

The fans have arrived -woohoo - so any new orders for the 1.5amp panel/box combo will come with a fan - unattached and no hole cut- to give people the option to install one if they like.

Well I've let slip elsewhere so may as well give the game away.... I'm getting some 5V "7 day" Timers made up. These have a usb input at one end and a USB output at the other. Using the LCD display you can then instruct the timer to switch on the Pi every weekday at say 11am for 15 mins and maybe every Saturday and Sunday for 1 hour etc. They are fully configurable just like a mains power timer. Using a script on the Pi it would be easy to get it to do some stuff, and then shut itself down waiting to be powered off. Around 2-3 weeks til these are available I should think. I'll offer these at low cost for people who've posted already to this site.

ForestBE
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Re: Current Cottonpickers experiments

Postby ForestBE » Tue Jun 18, 2013 5:57 pm

Dear Cottonpickers,

Thanks a lot for the explanations and clarifications. Reading thorough the reviews of most of the USB Power Packs you get this scary feeling that they will eventually explode in your face ...
One does not mess with LiPos!
That is why I am considering your solar panel with an USB timer. However, the solar panel would be connected to an adafruit LiPo charger with a 6000 mAh LiPo; from the charger into your timer and then further to the Pi.
I hope that this makes a saver and more reliable setup (compared to USB Power Packs).

With many thanks for your advice,

ForestBE


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