Ok I figured it out, you have to have a load connected and then connect the leads in series with one of the wires.
Steve.
Steve.
portable solar charger
- Thread starter ateallthepies
- Start date
yes, i use an led star for ease. Sorry, i could have written my first post better. I find the most accurate way is to read voltage first then resistance and divide to get current although it wont be far out doing it the direct way. What numbers did you get. real sun will produce more than a tungsten based light but i would hope to see at least 400mah.
Not sure if my meter is working properly but set on 2 A it's reading 0.003, set to 200 mA it's 0.3 and set to 20 mA it's 0.03 ? Would not say 300mA read as 0.300 set on the 2 A setting on the meter?
Steve.
Steve.
300mah would be 0.3 if using amps. presuming your meter doesnt have a separate mah socket. have a look at this. covers all readings
http://www.youtube.com/watch?v=bF3OyQ3HwfU
http://www.youtube.com/watch?v=bF3OyQ3HwfU
I had a 400 mAh output AA battery charger plugged in and split the lead going to it to attach the cables. My MM has a 10 A and 2 A socket (had to use the 10A socket as the 2 A gave no readings) but it also a dial with the DC current ratings from 10A, 2A, 200mA, 20mA, 2mA, 200micro A and 20 micro A.
Hopefully we will get some sun tomorrow and I can see what's what? I also went ahead and ordered a second XL panel so hopefully will get it this week.
Steve.
Hopefully we will get some sun tomorrow and I can see what's what? I also went ahead and ordered a second XL panel so hopefully will get it this week.
Steve.
Ok I figured out my 2 A port had a blown fuse so with that fixed I am getting proper readings using the dial settings. With my 60 watt tungsten light bulb as a source of light I'm getting 34 mA at the charger. This is obviously a rubbish amount of generated elecy so all's I can do is wait for some sun.
Ta for the linky to that MM demo, I now think my testing method is OK whereas before I was reading a 3 behind various numbers of zeros using the 10A port, with the 2 A port now working i'm getting more sensitive readings and it all makes sense now!
Steve.
Ta for the linky to that MM demo, I now think my testing method is OK whereas before I was reading a 3 behind various numbers of zeros using the 10A port, with the 2 A port now working i'm getting more sensitive readings and it all makes sense now!
Steve.
Today is overcast, no sun at all. My panel is sending about 60 mA to the charger, I have no idea if this is good or bad? Wish I had paid more attention in electronics class at collage
The cheapo charger in the pic is input rated at 6 volts at 800 mA with an output of 450 mA at 5 volts. I'm getting over 5 volts out the panel but with such low mA I wonder if the charger is actually doing anything or just charging real slow? Does an electronic gadget need full current or can they work with less mA but work just a bit slower?
Steve.
The cheapo charger in the pic is input rated at 6 volts at 800 mA with an output of 450 mA at 5 volts. I'm getting over 5 volts out the panel but with such low mA I wonder if the charger is actually doing anything or just charging real slow? Does an electronic gadget need full current or can they work with less mA but work just a bit slower?
Steve.
the fact that its drawing power means it will be charging but just really slow. In cloudy conditions what you are seeing is about the norm. my 12v 10w panel will not charge my iphone unless there is good sun but will put out about 150-200mah to a usb battery charger. Even my 40w panel doesnt put out huge current in cloudy conditions. As a rule from April onwards my 40w panel sustains a leisure battery that runs my home office (just a laptop and all my gadgets) but a long period of cloudy weather will see the battery dip low. to make sure of good chariging of usb devices in cloudy weather takes about 80w
This one - its great and holds the charge for some time!!!
http://www.amazon.co.uk/New-Trent-i...MP50/ref=sr_1_4?ie=UTF8&qid=1328979534&sr=8-4
Thanks for the heads up on this one...I decided to take the plunge and treat myself to one as I'm always carrying at least a couple of spare phone batteries around as well as a small top-up charger. With this I can charge my bluetooth headset. headphones, phone, etc all from the one source.
It arrived this morning already mostly charged which I topped up. I've now had a full charge for my phone from it and plan to charge anything else I can find with it but so far it's looking good and just what I was looking for..
It will be great for hillwalking, camping and such but for fishing as well where my GPS and bluetooth are on constantly as well as uploading stuff to my fishing club's blog. (The GPS isn't for finding my way around, my wife gets nervous when I take the kids fishing so it helps her see exactly where we are at any given time...personally, I think it's so she can at least recover my fishing gear to put on ebay).
BT, had some very hazy sun today and got up to 220 mA out my rig so I'm guessing a clear day at this time of year should produce around 300+ mA? Should get higher readings in full summer though? Looks like my 2 XL panels lego'ed together should give a minimum of 120 ish mA on a cloudy winter day or around 600 mA on a clear one? Should be no problem charging anything as summer progresses?
Not really worried about things taking a long time to charge though as it is more of an emergency gadget!
NS40, my Trent power pack arrived today as well! Have it on charge as we speak so I look forward to seeing how it performs? If it will take a charge from my panels I will be very happy!
Steve.
Not really worried about things taking a long time to charge though as it is more of an emergency gadget!
NS40, my Trent power pack arrived today as well! Have it on charge as we speak so I look forward to seeing how it performs? If it will take a charge from my panels I will be very happy!
Steve.
im working on a 10000ma battery pack which will hopefully charge my iphone and anything else and the total cost should be about £9. Will share details when ive finished it but im just waiting on a voltage booster.
any bright conditions really improve things and even full winter sunshine is quite effective. in full summer they can overheat and power drops. you cant win with these things lol.
any bright conditions really improve things and even full winter sunshine is quite effective. in full summer they can overheat and power drops. you cant win with these things lol.
got my gear today
Its overcast but half bright. The 18650 box is stonking. charges iphone 3g, 3gs and 4 with no adapter needed. Thats over 10amps of charge for under a tenner (excluding cells which i already had). panel charges the box too in overcast conditions but probably not putting much out. its happily charging from the usb port though as i type. Love the little volt meter too and ive just ordered a load of bits from DX to make some up given the amount of battery based kit i use. Noticed you can get the 18650 boxes on ebay for about £7.50 delivered (china). some piccies below. ignore date on phone, its my old one i use for testing kit im not sure about.
Its overcast but half bright. The 18650 box is stonking. charges iphone 3g, 3gs and 4 with no adapter needed. Thats over 10amps of charge for under a tenner (excluding cells which i already had). panel charges the box too in overcast conditions but probably not putting much out. its happily charging from the usb port though as i type. Love the little volt meter too and ive just ordered a load of bits from DX to make some up given the amount of battery based kit i use. Noticed you can get the 18650 boxes on ebay for about £7.50 delivered (china). some piccies below. ignore date on phone, its my old one i use for testing kit im not sure about.
So the box has a built in charger? Also does it take 4 cells and are they arranged all in parallel, there must be a boost circuit to up the voltage to 5-5.5 volts? Not bad for less than a tenner! Like you say if you have the cells already your sorted and if one ever goes bad you can just swap it out unlike the one I bought.
Steve.
Steve.
Hi Steve
yes it has a charge circuit built in that can use either 5pin mini usb or 3mm jack. Batteries are fitted in parallel and boosted to 5v. You dont even have to fit 4 cells. will work with just 1.
edit - does take 4 cells though
yes it has a charge circuit built in that can use either 5pin mini usb or 3mm jack. Batteries are fitted in parallel and boosted to 5v. You dont even have to fit 4 cells. will work with just 1.
edit - does take 4 cells though
Last edited:
My second XL panel just arrived
But there is heavy, heavy cloud cover
Will get some results later.
Steve.
But there is heavy, heavy cloud cover
Will get some results later.
Steve.
You may be right, I have heard of poor results with solar chargers especially with our weather, have not had clear sun since I bought my panels! My initial tests though are encouraging and with both my panels running I will easily have enough current to charge all my AA and li-on batteries as I only need 500 mA for the AA charger and 700 mA for the li-on.
Steve.
The box puts out 700mah of usb voltage power. There will be some inefficiency in taking the 3.7v of the lithium cells up to 5v but with genuine 3000mah cells this will still leave 10 amps of power. I accept that the solar panel will not replenish the pack unless there is full sun but i think its misguided to say its useless?
Cheers
Paul
Think I need to make a bag to carry all this crap lol. Thinking a respirator bag with neoprene cases for everything to slip into. could keep all my brights and power gizmos in one place
I need to sort all my stuff as well, it looks like a bomb has gone off in a electronics factory
Steve.
Steve.
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