Digital Volt/Amp Meter for Solar panel

I am planning to Measure and Display the Voltage and Current of my solar panel using a Parallel Interfaced LCD Module and a PIC Controller 16F877A...
I am having a hardtime doing it therefore i have some questions:

So far i was able to measure the voltage, but i also need to measure the current. Any idea??

Is there any other Microcontroller that Makes the job easier?

I appreciate everything you can help me with...

Thanks!

what about a current sense amplifier
Linear Technology - LTC6101 - High Voltage, High-Side Current Sense Amplifier in SOT-23

it measures the voltage across a sense resistor - you could probably feed the output of the LTC6101 into an ADC
a PIC16 would do the job but these days I would use a PIC24 - lots more power and IO and costs little more

Hi,

How about the simple Shunt resistor - you measure the voltage developed across it and then convert that to a meaningfull current reading.

Assume you are using a limiting resistor / divider when measuring the voltage from the panels ?

What language are you programming in ?

The method I have used in the past is to add a resistor in the ground side of the PV panel and measure the voltage across it with one analog input, then using a potential divider, drop the voltage at the 'top' end of the panel so it is within a safe range for the PIC and measure it on another analog input. You should protect the PIC from over voltage just in case a fault occurs. You can then calculate the current by measuring the voltage drop across the ground side resistor, measure the voltage by subtracting the bottom from the top and also calculate the power being drawn from the panel by multiplying the two together.

Brian.

Hi,

Here are some appnotes and projects using Microchip PIC for Solar Panel monitoring and data logging. If you find any of them useful please contact the relevant authors and thank them.

Hope these help you in your endeavor.

@bigdogguru: I think you forgot to add the link for those appnotes and projects on soalr panels. Can you please add it? i think they will help me a lot! Thanks

@betwixt: What i am doing is a voltage divider so that the voltage of the solar panel does not damage the PIC. I am using a relation so that when the Solar panel is outputting 21 volts (The Maximum possible) The Dividider Brings it down to 5 Volts (Max that the PIC can hold) And making some modifications to the code...Scale factor.

@wp100
How do i convert it to a meaningful reading?
i am using "C" languague!


@horace1
Thanks for that helpful link!

To ALL: I appreciate your adivises and time to assist me. I am still working on the project so if you can provide more it will be greatly appreciated!!!

Thanks!

---------- Post added at 12:03 ---------- Previous post was at 12:01 ----------

@bigdogguru: Nevemind... the link works fine. it did not load when i was reading it! Thanks!