Thank you all for reading this. (If this is posted in the wrong section of the forum, I trust the admin to move it accordingly).
I need some help with the following:
To use a solar panel (currently gravitating towards the "big blue 28W" model linked below) to power a DC 12V 1A input device (batter charger also linked below), the output voltage of the panel needs to be increased. The manufacturer says that two of the three USB ports provide 5V with a current that ranges between 0 and 2,4A (depending on conditions), while the third USB port provides 5V and zero to 1A of power output.
http://www.ibigblue.com/product/detail/?id=17
https://charger.nitecore.com/product/d2
1st question: I am almost sure that monocrystaline solar panels operate between 6 and 6,2 Volts (perhaps more variations exist depending on the source of the panels). Therefore, the manufacturer has already included some sort of step-down circuitry [or some other trick that allows him to power the USB ports with nominal 5V]. Can anyone guestimate how he may have gone about this, so that it can be taken into account in the rest of my questions?
2nd question: Can the output of the two - or even better all three - USB ports be combined to distribute the current requirement of 1A. If "yes" how can this be done?
3rd question: Since the whole solution is going to be [manually] portable, minimising weight while maximising reliability and longevity would be very welcome. So, if you believe that a battery or batteries are required between the solar panel and the battery charger, please try to adhere to the following "rules":
3.1 Keep weight to a minimum and prefer li-ion over other types of batteries (hopefully 18650 format for the sake of commonality).
3.2 I would prefer some redundancy (e.g. 3 "lipstick" power banks over one single power bank and/or a power bank with replaceable cells over one whose cells cannot be replaced).
4th question: Finally, how do I ensure that the battery charger [or any device for that matter] I intend to power off the solar panel is fed with no more and no less than 12V 1A DC (no need to fry it with over-current or over-voltage)?
5th question: Could the output of the combined two or three USB ports be available to me in an adjustable manner [selectable range of output voltage / current, as in some buck/boost converters I have seen] to power other devices? How do these converters manage fluctuations in their input current (e.g. from cloud coverage)?
6th question: Finally, heat dissipation, ruggedness and resistance to humidity will be of some concern. What can I do for my setup in this regard?
Thank you all for reading through this!
I hope to get some helpful answers.
I need some help with the following:
To use a solar panel (currently gravitating towards the "big blue 28W" model linked below) to power a DC 12V 1A input device (batter charger also linked below), the output voltage of the panel needs to be increased. The manufacturer says that two of the three USB ports provide 5V with a current that ranges between 0 and 2,4A (depending on conditions), while the third USB port provides 5V and zero to 1A of power output.
http://www.ibigblue.com/product/detail/?id=17
https://charger.nitecore.com/product/d2
1st question: I am almost sure that monocrystaline solar panels operate between 6 and 6,2 Volts (perhaps more variations exist depending on the source of the panels). Therefore, the manufacturer has already included some sort of step-down circuitry [or some other trick that allows him to power the USB ports with nominal 5V]. Can anyone guestimate how he may have gone about this, so that it can be taken into account in the rest of my questions?
2nd question: Can the output of the two - or even better all three - USB ports be combined to distribute the current requirement of 1A. If "yes" how can this be done?
3rd question: Since the whole solution is going to be [manually] portable, minimising weight while maximising reliability and longevity would be very welcome. So, if you believe that a battery or batteries are required between the solar panel and the battery charger, please try to adhere to the following "rules":
3.1 Keep weight to a minimum and prefer li-ion over other types of batteries (hopefully 18650 format for the sake of commonality).
3.2 I would prefer some redundancy (e.g. 3 "lipstick" power banks over one single power bank and/or a power bank with replaceable cells over one whose cells cannot be replaced).
4th question: Finally, how do I ensure that the battery charger [or any device for that matter] I intend to power off the solar panel is fed with no more and no less than 12V 1A DC (no need to fry it with over-current or over-voltage)?
5th question: Could the output of the combined two or three USB ports be available to me in an adjustable manner [selectable range of output voltage / current, as in some buck/boost converters I have seen] to power other devices? How do these converters manage fluctuations in their input current (e.g. from cloud coverage)?
6th question: Finally, heat dissipation, ruggedness and resistance to humidity will be of some concern. What can I do for my setup in this regard?
Thank you all for reading through this!
I hope to get some helpful answers.