Power Distribution Boards

One problem I’m constantly having in building medium-sized prototype robotics systems is power distribution. I’ve got enough sensors and things that I don’t want to have one massive wire junction tied into my power supply. Terminal blocks are sort of OK, but I’ve always felt they were a bit lacking and also didn’t provide any circuit protection. Recently, I’ve run across a few power distribution boards which look pretty nice and are pretty cheap, especially compared to the price of building a one-off.

The Altronix PD8 (Amazon) comes out of the security industry (alarm systems) and which takes up to 28VAC/VDC @ 10A as input on a pair of screw terminals and distributes it to 8 individually fused outputs on two strips of screw terminals. There is a handy slide switch to switch power on and off, along with an indicator LED. Dimensions are 5/25″ x 3.25″ x 1″. The board takes standard 3AG (1.25″ x 0.25″) glass fuses. For some odd reason, even though the instructions say the board is good to 10A, the main bus fuse I got was rated for 5A. The output fuses are 3.5A. A pretty good deal for around $20. Good documentation on the Altronix website, including CAD drawings. Altronix also makes 4 and 16 output versions, as well as PTC fused versions.

If you have a smaller robot, or just don’t need all the circuit protection, there’s the Miller Engineering #4805 (near the bottom of the page). Originally designed for lighted signs for model train sets, this takes in power via a pair of binding posts or a DC barrel jack and gives you 10 outputs on two rows of screw terminals. Dimensions are 4.5″ x 2.25″. In the original application, this took 4.5VDC and drove 180mA signs. This is a bit low for many robotic applications, but I’m sure the board can probably handle more current unless they really skimped on trace widths. As I mentioned, there is no circuit protection for this board. Runs about $15.