About: I used to get paid for designing computer and networking hardware and software. Now I design stuff for fun and give it away.

NOTICE: Please contact me at csatt1@gmail.com if you are interested in building the hardware for people who don't have the time, skills, or tools to do it themselves. I get requests occasionally from such people, but cannot do this myself.

IV Swinger 2 is an IV curve tracer for photovoltaic (PV) solar panels (modules). There is also a version that works with PV cells.

The total cost of materials is about $50 (for the least expensive version) but may be more to build a single IV Swinger 2 since that assumes some items are purchased in larger quantities. It also does not include shipping, tax, tools or the Windows/Mac laptop that is required to use it.

This is a successor to IV Swinger, which was used for Gil Masters' CEE176B class at Stanford in 2015 and 2016. IV Swinger 2 has been used for that class since 2017. It is my sincere hope that IV Swinger 2 will be used at other colleges and universities that teach PV principles. For that matter, it can be very useful for anyone wanting to learn about the effects of insolation/irradiance, temperature, and especially shading on the power production of a single PV module. While the software does support calibration, there are no guarantees as to the device’s precision or accuracy.

The following two YouTube videos demonstrate IV Swinger 2 in action:

Part I (7:02)

Part II (6:48)

The hardware and software designs and documentation for the original IV Swinger and IV Swinger 2 are on GitHub:

https://github.com/csatt/IV_Swinger

I also want to acknowledge Jason Alderman (whom I have never met or even corresponded with). I stumbled on his wireless IV curve tracer design (http://jalderman.org/?p=57), and that was the "Aha!" moment without which IV Swinger 2 might not have happened.

The original IV Swinger 2 designs (for PV modules and PV cells) use an Adafruit "Perma-Proto" board and hand-cut, hand-stripped, hand-soldered hookup wires for all of the connections between the resistors, capacitors, ICs, and power/ground rails. Hookup wire is also used for the connections between the Perma-Proto and the Arduino.

Now there are printed circuit boards (PCBs) available that provide all of these connections, making the construction much simpler, faster, and more mistake-proof. Furthermore, there are versions of the PCBs that support on-board solid-state relays (SSRs) instead of the off-board electromagnetic relays (EMRs).

It is still possible to build an IV Swinger 2 using a Perma-Proto; the documentation still exists and the software doesn’t care. However, it is recommended that moving forward, all IV Swinger 2 constructions use the PCB-based designs.

Still interested? First, let's get familiar with the basics of the hardware design so you know what you'll be building.