We are using Basebox2’s and rb951’s in an areas with unreliable power. It’s expensive to set up full solar power stations in some of these areas. It’d be great to use an external battery with usb outputs.
I think the question was to get a UPS-like solution and NOT a solar panel because it would be too expensive.
Of course the mUPS requires a battery, but it can be used to build a working solution. A USB battery cannot.
It’s expensive to set up full solar power stations in some of these areas
I understand he want’s solar panel also because of the solar battery from the link. An ups or mups with external battery is a better solution if there is some power out of the outlet.
Another gotcha with the USB batteries is that 99% of such batteries CANNOT be delivering power and be charged/topped-up at the same time!
So when you have a device that can be USB-powered (e.g. Raspberry Pi) and you have a suitable charger, it is NOT possible to make it into a UPS-like solution by putting a USB battery inbetween!
I have another device here that was advertised as “with USB battery” suggesting that this could be used to make it operate on unreliable power, but that simply cannot be done. The battery has a button to turn on its output and when you press that, it stops charging. And vice-versa. So you can make the device operate in charge/use cycles, NOT make it operate continuously while keeping the battery topped-up and available to power the load should the mains drop out.
Thank you all for your responses. I was hoping to use the main grid to power the devices and when the power went down shift to the usb battery. So we would not need to be charging the batteries and using them at the same time.
So if we have a USB battery that can deliver 2.4A at 5 v = 12Watts. The basebox 2 requires max of 10 watts. So from a power perspective it should be ok. But can the Basebox2 handle 2.4 A?
You cannot use a USB battery! A USB battery is 5V and the basebox requires between 12 and 24V. So it won’t work.
However, you can use that exotic device that you showed the Amazon link for.
It can output the correct voltage. But probably it will have the problem I mentioned before: you cannot wire everything
up and wait for the power to fail and the battery to take over automatically. You will have to have the basebox on its
original powesupply and the battery on a charger until the power fails, then you go to the basebox, remove the plug
of the original supply and connect the battery, and it works on the battery until it is empty. When the power comes
back you re-wire everything as original.
This is not convenient and it would not be required with the mUPS, where you install everything and it will automatically
switch over when power fails, decide when to charge the battery, etc.
Also, you probably want to know how long it will operate on the battery, and there is really no way of telling that.
Why? Because the manufacturers of those batteries are known to be outright LIARS. The specs they mention on
the website are inflated because they know the customers go for the highest figure and will not have the knowledge
to later check if the product they bought complies to those specs.
Example on your link: in the header it says “Weiyi 40000mAh Ultra Slim Portable Power Bank”.
When you scroll down, in the details it says: “Specification Capacity:33600mah(124.32Wh)”
See how they already have rounded up the 33600 to 40000?
But, the Wh spec indicates that the 33600 mAh spec is at 3.7V, the voltage of the actual battery in the brick.
When you select an output voltage of 12V, the Wh number remains the same (when the converter is 100% effective)
so the mAh number at 12V is only 124.32Wh/12V = 10.36Ah = 10360mAh.
That is quite a lot less than 40000. And I guarantee you that when you buy the unit and test it, it will be even less.
How much less, well it depends. Could be 4000 or so when it is a really crappy manufacturer, or 8000 when he is honest.
But he knows that 4000 or 8000 does not sell, and 40000 does, so that is what goes on the label.
Think more about something like this:
12000MAH Large Capacity Long Battery Life DC 12V Rechargeable Li-ion Battery Portable Li-ion Backup Battery For Camera http://s.aliexpress.com/J3yiqy6b
Or think about using the mppt solar charger with a 12v accumulator and approximately 15v power supply instead the solar panel.
Battery, and battery clustering
AC, DC and solar panel input for power sharing
scheduling option
voltage regulation
Charge regulation (for all batteries)
Alarm and communications bus
Bus for temperature sensors
Gigabit support
A, B and A+B Poe standards
Surge protection, short protection and overcurrent protection.