Solar setup for 10 baofengs

[jadant]

I am going to try to pick the brains of the awesome people of this forum. I'm trying to create a solar setup that will be able to fairly quickly charge around 10 cheap baofeng transceivers. So far I have acquired a 12V 100AH AGM deep cycle battery, a Morningstar PS-30M PWM ProStar Solar Charge Controller, and a 245 watt solar panel View attachment 96255
as well as battery connection and cables to charge controller. I guess I'm trying to figure out the cheapest most effective way to transfer the DC energy from the battery to charge the transceivers. Anyone got any idea which type cables could be useful or do I need an inverter? Does anyone have any experience with using this type of setup to charge 10 in a reasonable time frame. Any suggestions would be useful, such as do I need more solar panels, batteries, etc. As you can see I dont have any experience working with solar and am trying not to sink more money into the project than needed. Thanks. Jared.

 

[krokus]

How do you plan on connecting to the radios? Barrel connectors? Drop-in single unit chargers? Multi-unit bank charger? (Not sure if anyone makes a bank charger for CCRs.)

 

[dcr_inc]

Retevis has bank chargers for the CCR's.. look on www.retevis.com... Also on Ebay

 

[bchappuie]

I would just get an inverter and use 110V bank chargers.

 

[cmjonesinc]

I would just get an inverter and use 110V bank chargers.

The ac adapter with the bank charger mentioned above outputs 13.2vdc. It would be a waste of energy to use a dc to ac inverter to immediately turn that ac back in to dc to power the charger.

 

[mmckenna]

Inverters are not efficient, and when using solar, efficiency can be critical. As CMJones said, going from your 12 volt DC system to 110v AC and back to 12 volts DC isn't an ideal solution. You'll be losing a lot of energy converted to heat in the inverter and transformers. You could certainly do that, but you'd want to spend some time figuring out the actual current draw of the inverter when running all those wall warts, then designing your solar panel system accordingly. But solar panels (good ones) are expensive.

Keep in mind that the rating on the solar panels is for full sun. You'll not see full output the entire time the sun is up.

If the radio chargers do a 12 to 13.8 volt DC input, you'd save some juice by just running them directly off DC and skipping the wall warts and inverters.

 

[a417]

Keep in mind that the rating on the solar panels is for full sun. You'll not see full output the entire time the sun is up.

If the radio chargers do a 12 to 13.8 volt DC input, you'd save some juice by just running them directly off DC and skipping the wall warts and inverters.

The battery would be important, as every time a cloud passed overhead and the solar voltage dropped below the charger threshold for undervoltage, the cycle would likely restart - making charging time unreliable and longer than neccessary. God only knows how those CCR batteries would hold up with stop-again start-again cycling.

 

[jadant]

Inverters are not efficient, and when using solar, efficiency can be critical. As CMJones said, going from your 12 volt DC system to 110v AC and back to 12 volts DC isn't an ideal solution. You'll be losing a lot of energy converted to heat in the inverter and transformers. You could certainly do that, but you'd want to spend some time figuring out the actual current draw of the inverter when running all those wall warts, then designing your solar panel system accordingly. But solar panels (good ones) are expensive.

Keep in mind that the rating on the solar panels is for full sun. You'll not see full output the entire time the sun is up.

If the radio chargers do a 12 to 13.8 volt DC input, you'd save some juice by just running them directly off DC and skipping the wall warts and inverters.

Any idea if they make DC cables for the baofengs or baofeng chargers?

 

[jonwienke]

The battery would be important, as every time a cloud passed overhead and the solar voltage dropped below the charger threshold for undervoltage, the cycle would likely restart - making charging time unreliable and longer than neccessary. God only knows how those CCR batteries would hold up with stop-again start-again cycling.

Not really. Li-ion batteries don't have a fixed charge cycle, so a simple CVCC circuit will stop charging when the battery reaches full charge, even if charging is interrupted every few minutes. And that is what is in the Baofeng chargers.

 

[MarkVee]

Any idea if they make DC cables for the baofengs or baofeng chargers?

Yes, this one for example: www.amazon.com/BAOFENG-Output-Charger-Baofeng-BF-F8HP/dp/B06XNLPQKP I use a similar one for charging a single radio (in it's charging cradle) from a cigarette lighter socket.

So if I understand correctly you want to charge all 10 radios, in the desktop charging cradles, at the same time right?

The panel wattage and battery capacity look OK to me for this application. The panel is actually oversized, but no problem when using a charge controller. Double check yours, but pretty sure the Baofeng charging cradles require 10 volts at 500 mA each (or 5 amps @ 10 volts for charging all 10 at once), and that's in line with the 20 hour discharge rate (at ~12v) for your battery based on this.

So the problem, or missing piece, is you need a constant 10 volts to each charging cradle but the battery output is a (nominal) 12 volts and can go up to about 14.8 volts when it's being charged - so you need to step down the voltage.

Just one possible solution of many but this should work, get a DC-DC step down converter that is rated to handle the 12-15 volt battery input and the 10 volts @ 5 amps output, maybe this one: www.amazon.com/WHDTS-1-2V-35V-Converter-Adjustable-Constant/dp/B0819Y8PJZ

Wire the step down converter to the battery and adjust the output to 10 volts. 14 or 16 AWG lamp wire would be fine. On the output side of the converter attach both a positive and negative bus bar (www.amazon.com/Terminal-Power-Distribution-Block-Bus/dp/B07TJ2GPBF), this will allow wiring each of the 10 chargers to the converter fairly easily and cleanly. Wire each of the chargers to the bus bars with the same lamp cord, with an appropriate connector to fit the charging cradles, think this is the right sized ones (but double check): www.amazon.com/Xenocam-2-1mm-5-5mm-Camera-Adapter/dp/B01AGQVYQQ