HeatsinkUSA 5.886" x 25.5" Aluminum Heat Sink (1)
Mean Well ELN-60-48P Constant Current Drivers (2)
Cree XT-E Royal Blue LED (24) supplied by LED Group Buy
Cree XP-G Neutral White LED (12) supplied by LED Group Buy
Thermal Tape Pre-Cut (36) supplied by LED Group Buy
DIY Arduino Driven Controller
Weller WES51 Soldering Station
Well alright, a word about the design of the controller. I have been working with Amtel microcontrollers for awhile now. I like them because they are cheap, and easy to program. In the above picture you see three boards. The larger blue one is a development board. You would wire your circuits up on solderless bread boards and then connect jumper wires to the pins. The tiny blue one in the middle is actually the same as the larger one but only acts as a breakout board with no on board power regulation. The one on the right is the prototype board complete with the RTC and headers for a temperature probe.
This controller already has provisions for ATO, Wavemaker, Temperature Probe, LEDs and Water Level as part of the design. I am going to start with the LEDs and move on from there. In the software the foundations are already laid down for the extra additions later.
With respect to the LEDs, I plan to drive the XP-G NW LEDs at the stock 1300mA provided by the Mean Well drivers in a single series circuit. As for the XT-E Royal Blue LEDs, it gets a little more complicated. My plan is to run two parallel strings of twelve LEDs each. According to Kirchhoff’s Current Law, the total current is the sum of the currents through the individual branches. In this case the total current is 1300mA so that means there should be about 650mA available to each string. The current rating for these LEDs is only 1000mA so a failure of either parallel string will likely result in fried LEDs. As such I plan to employ, at the very least, fast blow fuses on each branch of Royal Blue LEDs. I am also toying with the idea of using a current mirror circuit to balance the current as well as offer another way shut down the LEDs in case of individual component failure.
I plan to suspend this fixture from my ceiling using braided cable or something similar. And I have a line on a fellow who will do plastic work for the cost of the materials. If that's the case, I may end up with a fancy little enclosure as well.
That's it for now, I'll be back updating as I go.
Edited by Cintax, 24 October 2011 - 05:59 PM.