Miscellaneous Elements

Wires and Connectors

Patch Cables

Wires and connectors allow you to connect the different electronic components of the system. All elements use XT30 connectors, which are keyed to fit only with the correct polarity. They are relatively easy for small hands to work with, at least compared to most alternatives. If the connectors are too hard to get together or pull apart, they can be lubricated with vaseline or other non-toxic lubricant.

Inputs always look like sockets (but are male), and outputs look like plugs (but are female). In workshops, we provide each builder four or five patch cables (plug on one side, socket on the other) and two Y cables. The Y cables have one output plug (female XT30) and two input sockets (male XT30), which allows builders to plug more than one power source output (i.e. two solar panels) into one input (a motor, or perhaps a solarengine and a motor.) We don't usually provide Y cables with one input and two outputs (the sort you might use to plug two motors into the output of a solarengine) because we find that splitting the output voltage that way makes the motors too weak.

Sourcing Parts

  1. 10 CM XT30 patch cables can be purchased on EBay from many different sellers. Be sure to shop around for price (especially with shipping) because it can vary dramatically from seller to seller. XT30 Patch on Ebay

  2. Y Cables. For input only Y cables, you'll need 1 Female (XT30 plug) to 2 Male (XT30 sockets). Here's a listing on EBay. XT30 Y on Ebay

Desired Improvements

  • We looked at a lot of connectors, but very few were robust, inexpensive, polarized, and easy to grip. XT30 has a bright yellow connector that makes the connections very visible, and is easier to grip than most. The ones we got from eBay were easy to insert and remove, unless they get sand or grit in them, in which case it helps to blow them out. But if someone finds a new connector that meets these criteria, for which inexpensive patch cables can easily be sourced, please let us know! Connectors are very important.

Past Revisions

  1. The 16 gauge wires can be a bit too firm and inflexible. We experimented with some 22 gauge smaller wires, which are plenty big enough to carry the small amount of current we are using. But these turned out to be too flimsy. In general silicon insulated wire seems better as the wire will usually have more "give" and flexibility to it. We're now using 18 gauge, but our 16 gauge wires aren't so bad.

Xt3022Gauge Patch Cable

Acrylic Mirrors


Acrylic Mirrors (usually A4 or letter size) are inexpensive and allow participants to experiment with reflecting more light onto the solar panels, which gives them noticably more power.

Desired Improvements

  • Somewhat larger parabolic mirrors - say approximately 30cm - would allow for much stronger concentrations of light to be focused onto the panels. We explored this but didn't find a simple and inexpensive means of building them. But there's great play potential here.