Six Outlet 12v Power Center

The goal of this project was to 1) make a power center that was comparable to the craftsmanship used in the Obsession telescope and 2) make a power center that could run most anything in the field. I got the basic plans at Astronomy Magazine's website featuring Joseph Kempter's Jan '96 article. It took about a month to complete with my first attempt deemed a "prototype". I am not a very skilled woodworker and relied on assistance from Glen Ward who made the box. Thank you, Glen! I did cut the various holes using my neighbor's shop and equipment (thank you, Rich!). I used a polyurethane stain combination for the finish and installed all of the hardware and electrical components. I'm pretty pleased (if you couldn't tell) of the outcome. I also managed to complete the project without zapping myself on the battery.

This project cost about $240. I know this seems expensive but I really went overboard on the battery (65 amp hour rated, deep-cycle marine). I could have easily saved $100 by getting a cheaper, lower capacity battery. My philosophy on batteries is this: always get the highest capacity you can afford because all batteries have a finite number of times they can be recharged. Fewer charging cycles should result in a longer useful life of the battery. I also used premium Baltic birch plywood, brass hardware and higher quality electrical components.

Marine outlet covers are a nice feature because they help to keep moisture and debris out of the outlets. All outlets are fused, as is the circuit supplying power to the meter and LED.

The volt meter was modified by drilling a hole to accommodate the installation of a red LED which provides indirect illumination of the meter face. Silicone sealant was used to secure the meter and switch in the box holes. Both the meter and the LED are switched, although I've found that keeping the switch on (and the LED illuminated) helps to let everyone know where the power center is in the dark.

Ten, 1/4 inch holes (five on each side) are for ventilation to prevent the build-up of any explosive gases from the battery. I didn't like the rope hinge called out in Kempter's article so I installed a locking hinge to keep the top open during recharging (or battery removal).

I like to compare this power center to that offered by Kendrick Studios. Granted, this isn't as high tech as those offered by Kendrick but this unit really complements my Obsession telescope. Plus, I have more outlets and should get at least twice as many viewing hours' worth of use between charges (compared to the 33 amp hour unit). If you're interested in this design e-mail me and I'll return e-mail the design specs and materials list (Adobe PDF or MS Word 97 document).