What is the easiest way to accomplish this task? I'm having a hard time finding an inexpensive existing product that will perform this task + log it so statistics can be run on the information. It needs to support 170vdc and 8a.
I've attached an image from an ebay item that will read the volts and amp, but not log.
![s-l500[1].jpg](https://europe1.discourse-cdn.com/arduino/original/3X/d/1/d1022054763b92caa0a48fc292e84460cbc472a5.jpg)
170 volts DC is a dangerous voltage -what does the panel supply ?
If it’s feeding and AC system via an inverter, then that might be easier / safer to connect to.
If you don’t have qualifications for this sort of work , don’t do it .
I know what I'm doing and how to do it safely. I just want to log the information without needing to run the electricity through a dc -> ac converter.
scotty562:
I just want to log the information without needing to run the electricity through a dc -> ac converter.
So you want to measure/log voltage and current of the panel without connecting the panel to a load?
Open circuit voltage is useless information, and only a load can draw current.
There should be a MPPT device between panel and load that constantly adjusts voltage/current to extract the most energy from the panel with changing light conditions and panel temperatures.
That MPPT device should already have the voltage/current/power info available.
Leo..
My setup currently has a load. A MPPT device would be great if I was charging batteries, but to run my load it's not required. One of THESE little guys can read the volts and amps. I'd imagine the hall sensor it's using could be rigged up to an Arduino somehow..
scotty562:
My setup currently has a load.
What load.
The load has to variable resistance or constant voltage (battery) to compensate for the changing power output of the panel.
And 170volt/8Amp (1360watt) can't be taken by a simple resistor or zener diode.
Leo..
The load is a 1500 watt 120v heating element for testing. Initial tests have been quite fun as well as successful. A large Dunkin donuts size cup of water boiled quite quickly at <80v (cloudy).
I don't see the point in testing a solar array with a fixed resistive load, apart from having some fun.
Solar panels behave more like a current source, unlike batteries, which are a voltage source.
To test performance of a panel, you need to keep panel voltage constant at the optimum power point.
Current can also be measured with a 10Amp ACS712 hall sensor module and an Arduino.
Voltage can be measured with a voltage divider to <= 5volt.
Plenty of examples for that on this site. Use the search field on top of this page.
Take care. That voltage is lethal, and DC is more dangerous than AC.
Leo..
Thank you for the advice. The future load Wii be an acdc12c which is a solar mini split which is designed to run directly off of solar panels.