Switches are simple devices that consist mainly in Ethernet ports and a processor that performs the switching, without containing too many other components. As part of the plan to reduce current consumption, a D-Link switch has been acquired that turned out to require input. However, all the hardware in the system is meant to work at such that a buck converter will be embedded inside the switch in order to drop down the voltage from from the solar panels and down to that is required by the switch. Furthermore, the buck converter is also a stabilizer, that works with a large input range and requiring the input voltage to only be at least above the consumption voltage.

The D-Link switch is rated at being a simple device without any sort of management that just routes packages between the available ports. The switch additionally does not require a lot of current to operate, reaching up to a maximum of such that the buck converter can be a minimal device that can be embedded inside the switch itself.

First, the switch has to be opened up, which seems to be an easy task with four screws on the side that allows the top cover to slide off, and then two different screws on the inside that holds the PCB in place.

The power jack is to be found on the side of the PCB and is soldered down. The plan would be to remove the power jack in order to sever the positive power line and feed both ground and the positive line into the buck converter. Here, the difficulty lies in removing the jack without damaging it such that it can be fitted back in place after the modification.

With some solder wick and a heat gun, the jack is removed without damaging the PCB after which the PCB is cleaned up. The back pin of the power jack, representing the positive lead, is then bent upward in order to allow a wire to be connected and power drawn to the buck converter. As for the buck converter itself, it is glued down onto the PCB using liquid tape - alternatively, of course, hot-melt glue should also do a good job but the liquid tape is far superior because it leaves even less of a residue in case removal is desired.

Wires are soldered to both input and output pins of the buck converter that will sap power from the input jack and then feed the converted voltage into the PCB. Of course, the PCB is tested for connectivity in order to find a better place to connect the output wires.

The red wire coming out the extreme end of the buck converter is bent and slid underneath the other wires in order to be connected to a point on the PCB that has been measured to connect to the middle (positive) pin of the power jack. The black wire, the ground is connected together to the input ground on the side of the input jack given that there is a lot of clearance on the small tin lamelle of the ground pin of the power jack.

The D-Link switch is reassembled and then connected to in order to check that the build is working properly.

As it was mentioned in the environmentalism section, the hardware should scale to the power generated, preferably without having to step-up nor step-down the voltage due to the losses incurred in doing so.

Unfortunately, there are cases such as very basic switches that run on a different voltage than the setup - in this case, fortunately, the voltage required is less than the voltage being generated such that losses are minimal compared to having to step-up the voltage. That being said, the modification allows reducing some cabling by allowing the switch to accept as input by using the buck converter to scale down to as required by the D-Link switch.