06-27-2018, 06:54 PM
Hi everyone, this is my first post on the forums, so I thought I'd make it a good one.
A few notes:
I have tried to do the best showing aquarium I can without spending ridiculous amounts of money on my equipment. I am very much a DIY kind of guy, which is why I went with Robo-Tank over any other tank management system. I have also looked for lower cost equipment that can do what I need and that can be modified to expand its usefulness. I am running an ~90 gallon total capacity saltwater Reef tank with a predator refugium (corals, clowns, angelfish, starfish, CUC emerald shrimp, anemones in my reef tank and two snowflake eels in my refugium) + a sump for all of my filtration and equipment. Due to the fact that I am currently running smaller tanks (55gal reef, 25gal fuge) and I plan on expanding in the future I could not justify spending high hundreds to low thousands on lighting, considering I will eventually transition these for a larger tank. I also needed full spectrum lighting to ensure proper coral/anemone growth, and to enhance fish coloration. Thus, the Fluval lights.
Anyone who has purchased the Fluval Pro series lights has probably considered the Fluval Wifi controller, which I purchased, and deemed lower than whale dung in quality and usability. Between a PTP-only wifi connection to control it, the fact that it gets HOT when operating, its $90 USD price, and that whenever power is lost to it the unit has no clock memory, I deemed it an utter piece of crap and terribly overpriced piece of garbage.
I decided to control my pair of Fluval Pro Reef lights with the Robo-Tank. In doing research, I learned that there was one small (major) issue with this - when the PWM signals are connected directly, OFF on the Robo-Tank PWM signal results in about 33% lighting, and FULL results in lights OFF. After some research I discovered why: The arduino boards do 0-5V PWM (for power feed control), while the Fluval Pro lights are wired for Ground Circuit control of the PWM (open circuit to grounded). In short, I needed to reverse the polarity of the PWM signal coming from the Arduino board inside of the Robo-Tank so that I can control my lights.
Spoiler alert: I figured it out. This will work on ANY LED lighting that is ground controlled PWM, just be aware that YMMV.
The below tutorial is designed for use with TWO Fluval Pro reef lights. Expand or reduce quantities as necessary to meet your needs
Parts list:
The Arduino board PWM outputs are geared to go from supplying zero voltage at minimum to 5V at maximum, because the arduino utilizes a PNP transistor to manage PWM outputs (in short, it controls the positive side of the PWM circuit). The Fluval LED Lights are geared to receive an open circuit at minimum and a closed (grounded) circuit at maximum (in other words, it controls the GROUNDED side of the circuit). In other words: no connection = lights off, full connection = lights MAX. Thus, we need to convert 0-5V to Open-Closed from the arduino. The easiest way to reverse the control is to substitute an NPN transistor in each control circuit to effectively REVERSE the voltage. The TIP122 is a fairly common circuit, offers decent power/amperage capability, and is highly recommended for arduino based projects. Also, it is CHEAP. We will take the PNP signal output from the arduino (wihch gives a positive voltage output) and connect that to the control circuit side of an NPN transistor (which controls an open/grounded circuit) to basically reverse voltage and allow us to control the Fluval LED lights.
The problem:
Arduino and Robo-Tank outputs a POSITIVE PWM signal. Fluval Pro LED requires a GROUNDED PWM signal
Steps I took:
When completed the result is a PWM controllable Fluval LED Pro lighting setup. I can dim and control the lights and the total power draw is well within the 5A capacity of the TIP122 transistors.
A few notes:
More pictures of my setup available upon request
A few notes:
- This post/tutorial assumes you have a basic understanding of electrical/electronics and very basic knowledge of transistors. If you do not, Google and Youtube are your friends - I highly recommend researching transistor polarity (NPN transistors and PNP transistors, their differences, polarity, and usages), PWM equipment, etc.
- DISCLAIMER: I am in no way an expert. I have no formal training, and I do this for my own entertainment and to suit my own needs. I claim no responsibility for any actions that you may take after reading my walkthrough, and this is strictly AT YOUR OWN RISK. The fact that I am willing to risk damage to my $400 in LED lighting does not in any way qualify me as an expert (if anything it qualifies me as reckless and an idiot) - so basically use my tutorial at your own risk. IF I have a failure in the future I will post it, and document as much as I can about it.
I have tried to do the best showing aquarium I can without spending ridiculous amounts of money on my equipment. I am very much a DIY kind of guy, which is why I went with Robo-Tank over any other tank management system. I have also looked for lower cost equipment that can do what I need and that can be modified to expand its usefulness. I am running an ~90 gallon total capacity saltwater Reef tank with a predator refugium (corals, clowns, angelfish, starfish, CUC emerald shrimp, anemones in my reef tank and two snowflake eels in my refugium) + a sump for all of my filtration and equipment. Due to the fact that I am currently running smaller tanks (55gal reef, 25gal fuge) and I plan on expanding in the future I could not justify spending high hundreds to low thousands on lighting, considering I will eventually transition these for a larger tank. I also needed full spectrum lighting to ensure proper coral/anemone growth, and to enhance fish coloration. Thus, the Fluval lights.
Anyone who has purchased the Fluval Pro series lights has probably considered the Fluval Wifi controller, which I purchased, and deemed lower than whale dung in quality and usability. Between a PTP-only wifi connection to control it, the fact that it gets HOT when operating, its $90 USD price, and that whenever power is lost to it the unit has no clock memory, I deemed it an utter piece of crap and terribly overpriced piece of garbage.
I decided to control my pair of Fluval Pro Reef lights with the Robo-Tank. In doing research, I learned that there was one small (major) issue with this - when the PWM signals are connected directly, OFF on the Robo-Tank PWM signal results in about 33% lighting, and FULL results in lights OFF. After some research I discovered why: The arduino boards do 0-5V PWM (for power feed control), while the Fluval Pro lights are wired for Ground Circuit control of the PWM (open circuit to grounded). In short, I needed to reverse the polarity of the PWM signal coming from the Arduino board inside of the Robo-Tank so that I can control my lights.
Spoiler alert: I figured it out. This will work on ANY LED lighting that is ground controlled PWM, just be aware that YMMV.
The below tutorial is designed for use with TWO Fluval Pro reef lights. Expand or reduce quantities as necessary to meet your needs
Parts list:
- 2x Fluval Pro Full Spectrum Reef grade lights (though this will work for ALL PWM Fluval lights that are compatible with their Wifi controller) - Cost NC, already had them. If you are looking for a complete start-up, $220USD for the 36 inch, $180USD for the 24-inch, so $400USD total
- Fluval Wifi Controller: I scrapped mine for this so as to not cut my power/light cords, however if you are comfortable cutting your cords and wiring a permanently attached module to your lights then you can save the money here - cost $90 USD
- Robo-Tank or equivalent arduino-based controller (assuming you already have it, otherwise this tutorial does not apply) - price: NC
- Generic breadboard, 5cmx7cm for my needs (you could use smaller or larger - I chose one that fit snug inside of the casing for the Fluval Wifi Controller) - Price: Came in a pack of about 36 pieces from Amazon for $10, so if you have them lying around, FREE, otherwise up to $10 for a pack of breadboards
- 4X TIP122 transistors (any NPN transistors will do) - I chose these for their 5A/100V power rating since my power adapters for my lights are max 2A@24V - cost $11.20USD for 10, or $1.12/ea, so $4.50 for this project
- 4X heatsinks, 10mmx10mm (you could use smaller or larger, and I am not convinced that these are completely necessary in the first place - I err on the side of caution) - 12 pcs for $9 on Amazon, so about $3USD total here
- Soldering Iron, wire, solder, flux, etc - I already had all of this, so no calculated cost here
The Arduino board PWM outputs are geared to go from supplying zero voltage at minimum to 5V at maximum, because the arduino utilizes a PNP transistor to manage PWM outputs (in short, it controls the positive side of the PWM circuit). The Fluval LED Lights are geared to receive an open circuit at minimum and a closed (grounded) circuit at maximum (in other words, it controls the GROUNDED side of the circuit). In other words: no connection = lights off, full connection = lights MAX. Thus, we need to convert 0-5V to Open-Closed from the arduino. The easiest way to reverse the control is to substitute an NPN transistor in each control circuit to effectively REVERSE the voltage. The TIP122 is a fairly common circuit, offers decent power/amperage capability, and is highly recommended for arduino based projects. Also, it is CHEAP. We will take the PNP signal output from the arduino (wihch gives a positive voltage output) and connect that to the control circuit side of an NPN transistor (which controls an open/grounded circuit) to basically reverse voltage and allow us to control the Fluval LED lights.
The problem:
Arduino and Robo-Tank outputs a POSITIVE PWM signal. Fluval Pro LED requires a GROUNDED PWM signal
Steps I took:
- I gutted my Fluval Wifi controller. As far as I am concerned, it is garbage and I could not justify charging someone else for that hunk of garbage, so I decided to repurpose the wiring terminal connectors and casing for my project. I did discover the wiring colors and pin-outs in the process:
- WHITE: power (24V) to the lights
- YELLOW: ground (0V) to the lights
- RED: PWM daylight signal to the lights
- BLACK: PWM moonlight signal to the lights
- I kept the electrical connectors, de-soldered them from the board and cleaned up the wire ends. I then took my 5cm x 7cm board and soldered two runner wires from one end to the other to act as primary power for the lights + I joined the E terminals for each light (1+2, 3+4) together and soldered these to the common grounds (yellow feed wires from the plugs)
- I soldered 4 TIP122 transistors in place at the output end of the board. I staggered them so I had room to run a power/ground wire between them for the CH1 and CH2 lights (1st Pro light and 2nd Pro light)
- I wired in the output connectors with ground and power hooked up, then connected the BLACK and RED wires of each plug to the C terminals of their respective TIP122 transistors
- I used an ethernet cable and wired the ORANGE/ORANGEWHITE and BROWN/BROWNWHITE wires to the ground (yellow) circuits of the connectors 1 + 2 respectively
- I wired:
- BLUE wire to the B terminal of transistor 1 (for LED 1 daylight control)
- BLUEWHITE to the B terminal of transistor 2 (for LED moonlight control)
- GREEN to the B terminal of transistor 3 (for LED 2 daylight control)
- GREENWHITE to the B terminal of transistor 4 (for LED 2 moonight control)
- These wires were then connected to the GROUND and PWM 1-4 outputs
- I then packaged the circuit board inside of the original Fluval Wifi controller, drilled a hole for the wire in one end, and connected it to the Robo-Tank and the LED lights through the original Fluval Wifi plugs. When I programmed the lights I had full range from full OFF to full ON, with the Robo-Tank level of LED intensity adjustments we have all come to expect.
When completed the result is a PWM controllable Fluval LED Pro lighting setup. I can dim and control the lights and the total power draw is well within the 5A capacity of the TIP122 transistors.
A few notes:
- I actually went through 8 TIP122 transistors and 2 breadboards, simply because I am terrible at left-right identification, especially when reversing the transistor orientation
- I gutted a perfectly good $90 Fluval Wifi controller to do this - you can cut your wires and save the $90 if you are willing to void your LED lighting or power brick warranty
- I have only had this running one day. It is still running way cooler than the original Fluval LED Wifi brick, but I still felt this worth mentioning.
More pictures of my setup available upon request
