Solar Remote Station Power Circuit

Thread Starter


Joined Jun 8, 2017
I am an electrical engineering student doing a work term for a university doing magnetic field research and building a remote monitoring station to be put in the field. Despite my couple years in school, I have very little practical knowledge of power systems and the way they work so I would appreciate any guidance you could give me.

I have a solar panel and turbine leading to a charge controller (Phocus CIS-N). This powers the two 12V batteries in parallel and the load output leads to my main breaker. With this system I have to power:
Power Supply Unit ( 12V 1.25A )
BulletPlus Modem ( 12V 2A )
BeagleBoneBlack ( 5V 2A)
I have a CUI Inc 12V to 5V converter that outputs 5VDC 3A to power the BeagleBone. I have attached a rough drawing of the circuit if it is easier to visualize.
Station Power.jpg

I am very new to power calculations and have never set up a circuit on my own so I am wondering if there is someway that I have to limit the input current into my devices or if they will only draw what they need. I realize that this might be a really simple question but I have almost no experience with power circuits.

Thank you in advance


Joined Sep 9, 2010
They will only draw what they need, when supplied the voltage (range) they are designed for. No worries. Don't feel bad, this is one of the most frequently asked questions here. I like to remind folks of light bulbs: You don't need to worry about anything other than supplying them their designated voltage.

Unfortunately, LEDs are very common these days and they are a glaring exception to this. They'll conduct as much current as you can supply until they blow like a fuse. You can make them work by controlling voltage within a very narrow range, but in general you control the current supplied to them.

But anything that is labelled for a particular voltage will be safe to supply with that voltage without controlling current. Of course there are always exceptions to every rule.