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[on:]

Hello frnds,
I am using arduino uno and i want to measure the current from the solar panel for my project , i don know what to interface to read the current, and i am newbie to arduino.

Please suggest some ideas ,

The current rating is from 0-5 A DC

[Reply #1 on:]

Put a small value, precision shunt resistor in series with the cell and measure the voltage drop across it.

[Reply #2 on:]

Hi,

I've used a few of the hall effect current sensors from Pololu for this type of thing also.  In a project on a boat I measured solar and generator input as well as total battery discharge using 3 of these modules.  I also use them in my benchtop power supply.  This +/- 5A one based on Allegro ACS714 will give you the best resolution for the range you're measuring.

Cheers ! Geoff

[Reply #3 on:]

Thank you Afremont and Strykeroz,

To strykeroz : can u also tel me how to design a dc-dc converter , and tell about your solar project , i have to design a solar charge controller,, it will be very useful for me ,

[Reply #4 on:]

Hi

Unfortunately neither of those projects will be too useful to you I think. The bench supply uses an ATX PSU with power broken out to 3v3, 5, 12 and variable posts on the enclosure.  A 20x4 character display outputs the current drawn from each... Plus temperature and a clock since it was already over the top.

The power hub on the boat is really a fuse box and power distribution board with a screen. The solar and outboard power are routed through it before the battery and all battery output goes through it also. This gives a simple indication of total charge or discharge of the battery since reset, instantaneous and cumulative moving average for those statistics... And cabin temperature, because I had extra pins

Geoff

[Reply #5 on:]

Atmel has an application note on battery charging. Starting in section 3.3 they start explaining the voltage and current measuring.

With respect to solar panels Tim Nolan's MPPT design is a must read.

[Reply #6 on:]

Thanks Chagrin

Those links were so useful

[Reply #7 on:]

Put a small value, precision shunt resistor in series with the cell and measure the voltage drop across it.

In solar battery charging systems every bit of energy is precious. A current shunt is just throwing away energy. Granted that it is a small amount but, if it can be avoided it should be. The use of a Hall sensor would be my first choice. Search ebay and you will find Hall sensors ranging from 5A to 30A .

[Reply #8 on:]

Put a small value, precision shunt resistor in series with the cell and measure the voltage drop across it.

In solar battery charging systems every bit of energy is precious. A current shunt is just throwing away energy. Granted that it is a small amount but, if it can be avoided it should be. The use of a Hall sensor would be my first choice. Search ebay and you will find Hall sensors ranging from 5A to 30A .

True, but the first couple of Hall sensors that I checked out used 50mW while operating so you'd have to be careful.