The solar instrumentation has been lacking for a couple of months since the solar panels’ current sensor blew up. It took 2 months because there has been a lot mistakes and learning along the way. It should have been simple, replace the 30A sensor by a 100A one right?
Well it wasn’t. First I ordered the wrong 100A sensor, meant for AC use. Then I had a myriad of issues around calibration.
- at the 5V input port, a 0V reading didn’t translate to 0A, this sensor goes from -100A to 100A so it is 2.5V which translate to 0A.
- with the skew from miscalibration, the value I was getting made no sense for what I know the panels can make
- orientation matters as again, this sensor can read negative values
- a cloudy day makes fluctuations hard to detect
- moving the sensor from one interface kit to another after calibration resulted in another skew.
All these little things I could have picked on their own, but together they conspired to make me thoroughly confused and left me seeking support from the Phidgets forums. I was once more impressed by Phidgets, the help I got was fast and efficient. Phidgets are more expensive but I was proven once more that they are worth every penny. They have many other advantages, I have nothing but good things to say about them.
Calibration, I really need to tidy things up in there
I’ve learned a LOT of lessons with this one. Not the least of which is to be ok with the imperfections of analog data. I’m a discrete data type of guy, it doesn’t come naturally to accept skews & variations.