flygja
Member
Here's are some pics from my DIY LED lighting. I used 12 pieces of Cree XR-E 3W LEDs driven by 2 Luxdrive 1000mA buckpucks. The whole thing is powered by a 24V 4A laptop power supply.
It all started with a bog standard Dolphin 60cm 2x18W lighting unit. Ripped out all the innards and cut a whole on the top for a fan. A fan is needed because LEDs do get very hot and their reliability is directly related to its operating temperature.

These are the buckpucks I used. They are constant current drivers meant for LEDs. Won't go into the science but LEDs need a constant current to maintain a constant output. These are also dimmable, which adjusts the current.

Power comes into the unit via the side cap. I removed the original AC cable and replaced it with a DC socket. You can also see the potentiometer I added for dimming. It worked for the first few days but it no longer dims. No idea why, too lazy to rip it out to find out. At least its brightest in default mode.

Bought a standard 2x20W aluminium reflector and cut it down to size so it fits into the casing. Note complex calculations happening 😀

A test run once all the LEDs are connected. LEDs are supposed to be connected in series - 6 LEDs to one buckpuck.

LEDs are then glued with thermal paste + 2 drops of super glue on the side of each LED.

The fan is a normal 12V 80mm PC case fan. Had to attach a 5W 180 ohm resistor inline because my power supply was 24V.

Fan is then attached to the casing.

Everything is then slotted into the casing. I added some silicon glue on each side to hold the reflector in place.

Test firing!

What it looks like from the bottom. Don't forget to put the acrylic splash protector back!

It's been running for almost 2 months now with no issues (except the dead dimmer). Growth has been pretty good, with Rotala nanhensjan growing about 2 inches per week and Rotala wallichi growing an inch a week and maintaining its red colour. Still waiting for Jap hairgrass to take off. Limnophilla sp Vietnam is starting to creep!

Questions and comments are most welcomed.
It all started with a bog standard Dolphin 60cm 2x18W lighting unit. Ripped out all the innards and cut a whole on the top for a fan. A fan is needed because LEDs do get very hot and their reliability is directly related to its operating temperature.

These are the buckpucks I used. They are constant current drivers meant for LEDs. Won't go into the science but LEDs need a constant current to maintain a constant output. These are also dimmable, which adjusts the current.

Power comes into the unit via the side cap. I removed the original AC cable and replaced it with a DC socket. You can also see the potentiometer I added for dimming. It worked for the first few days but it no longer dims. No idea why, too lazy to rip it out to find out. At least its brightest in default mode.

Bought a standard 2x20W aluminium reflector and cut it down to size so it fits into the casing. Note complex calculations happening 😀

A test run once all the LEDs are connected. LEDs are supposed to be connected in series - 6 LEDs to one buckpuck.

LEDs are then glued with thermal paste + 2 drops of super glue on the side of each LED.

The fan is a normal 12V 80mm PC case fan. Had to attach a 5W 180 ohm resistor inline because my power supply was 24V.

Fan is then attached to the casing.

Everything is then slotted into the casing. I added some silicon glue on each side to hold the reflector in place.

Test firing!

What it looks like from the bottom. Don't forget to put the acrylic splash protector back!

It's been running for almost 2 months now with no issues (except the dead dimmer). Growth has been pretty good, with Rotala nanhensjan growing about 2 inches per week and Rotala wallichi growing an inch a week and maintaining its red colour. Still waiting for Jap hairgrass to take off. Limnophilla sp Vietnam is starting to creep!

Questions and comments are most welcomed.