Arduino controller
- Thread starter eagle
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vbsaltydog
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If you can match the power then the motor shield may work, the problem is that the meanwell driver input signal uses very low amperage and DC motors require higher amperage so in one sceanario you must increase the voltage and in the other scenario you must decrease the amperage. Take your pick.
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eagle
Active Member
Right. What im thinking is taking the meanwell out and just driving the leds by dc voltage from a motor shield. Match your power supply to the motor shield with your max voltage on the leds. Then use digital psm to dim the led.
vbsaltydog
Active Member
The purpose of the meanwell driver is to deliver variable voltage at a constant current (hence the term constant current driver), you would need to hold the current at a constant current (~750mA) while varying the voltage from the motor shield.
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eagle
Active Member
Why couldn't you run constant voltage with variable current. ie PWM. I could see it working either way as it's just a dc voltage and current to a dc led. You don't have to use the analog write function on arduino either. You can just write your code to blink the led in different variables.
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eagle
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No problem dorky. I'll help out all I can. It's a learning process and maybe you'll figure something out that I can learn from. I really haven't looked at the led side yet as I still have halides and I'm working on pump control and reading inputs from probes and liquid level sensors. I haven't found anything that is very hard about it yet, or that there isn't a lot of information about it. Just google what you're trying to do and there is something out there about it lol. The arduino is still relatively new and growing by the day. When you look at what it is and what it's capable of doing I think it's a big step forward in automation. I had no experience in electronics other than building some computers but it's getting easier everytime I read about it or put something together. I think my brother was even surprised at how easy it was to load up an example sketch in the arduino IDE and start controlling stuff or reading an input. I know everyone's a little different but I've always been the type to jump right into something and figure it out as I go. I figure if someone else can do it then there's no reason why I cant figure it out and do it to. I'm sure that anyone that has a reef tank has some of the same characteristics because most people I know would've stopped at freshwater lol. Just because it's easier.
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eagle
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Hey Dork,
I have looked into it a little. Here's a site/calculator to design an array of led's. LED series parallel array wizard I'm not sure what led's you are looking at. I looked at the cree 3 watt datasheet and plugged in the numbers here as per what I saw there. I basically figured a 12 led array. I know when I get to that point I would be breaking down the different colors into different arrays of led's. Whites, blues etc. So 12X3 watt led's would be 36 watts. So I figured using a 36 watt power supply. From what I see the forward current with cree would be 350mA. I did see it says 1000mA max. So I used 350mA in the calculator. Dunno if that's correct. It designed the array and says to use a 1 ohm resistor. I have also been looking at pwm and it seems to be a common way to control brightness of led's with a microcontroller. Instead of adjusting the voltage up and down to adjust brightness, a microcontroller would adjust the on off cycles by milliseconds. It basically blinks faster than your eye can see. The voltage stays constant. With your dimmable driver the voltage is adjusted up and down to control the brightness. I don't believe this driver is necessary. If you look here at the jarduino controller user manual he is using pwm to run all his led arrays. I figured he was because in his video I could see the power supply run to the arduino in the hood. JARDUINO USER MANUAL v1.2 beta.pdf - jarduino-aquarium-controller - USER MANUAL for Jarduino v1.2 (beta2 release) - Jarduino Aquarium Controller v1.2 - Google Project Hosting
I have looked into it a little. Here's a site/calculator to design an array of led's. LED series parallel array wizard I'm not sure what led's you are looking at. I looked at the cree 3 watt datasheet and plugged in the numbers here as per what I saw there. I basically figured a 12 led array. I know when I get to that point I would be breaking down the different colors into different arrays of led's. Whites, blues etc. So 12X3 watt led's would be 36 watts. So I figured using a 36 watt power supply. From what I see the forward current with cree would be 350mA. I did see it says 1000mA max. So I used 350mA in the calculator. Dunno if that's correct. It designed the array and says to use a 1 ohm resistor. I have also been looking at pwm and it seems to be a common way to control brightness of led's with a microcontroller. Instead of adjusting the voltage up and down to adjust brightness, a microcontroller would adjust the on off cycles by milliseconds. It basically blinks faster than your eye can see. The voltage stays constant. With your dimmable driver the voltage is adjusted up and down to control the brightness. I don't believe this driver is necessary. If you look here at the jarduino controller user manual he is using pwm to run all his led arrays. I figured he was because in his video I could see the power supply run to the arduino in the hood. JARDUINO USER MANUAL v1.2 beta.pdf - jarduino-aquarium-controller - USER MANUAL for Jarduino v1.2 (beta2 release) - Jarduino Aquarium Controller v1.2 - Google Project Hosting
I believe you can just get a simple motor controller/shield that supports pwm and a power supply (match voltage and total amperage to the voltage of your array) and simply use the pwm function of the arduino to control the brightness however you like. This should be much cheaper than buying drivers as most motor shields will control 4 seperate dc motors. That could be 4 different led arrays. There are a ton of motor shields out there that will handle different voltages and amperage. And there are a lot of switching power supplies as well. I hope this helps ya out some D. Just research it.
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eagle
Active Member
Ok, going over the datasheet better CREE XP-G R5 5W Cool White LED - Rapid LED and getting my head wrapped around this a bit. Wiring an array of Cree 5 watt led's in series. From the data sheet the max forward current is 1500 mA. So I used 1000 for forward current, and at 1000mA forward current the forward voltage says 3.1. So with wiring 10 of them in series you would need at least a 32 volt power supply. That's what I am getting from this calculator so far lol.
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eagle
Active Member
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eagle
Active Member
Dorky and I have found some more info about the led's. Most people are driving them via constant current controllers. You can do it via a power supply and resistor but with these higher power led's it's recommended to use a constant current power source instead of constant voltage. When you look at the datasheet from cree the difference in even a half a volt is really dramatic in output. So I've looked around and dorky has too and these are what most people are using. I found these on Ebay for cheap. Will drive 5 amps of led's. Voltage and current can be adjusted. DC 5A Buck Converter Constant Current Solar Battery Charger LED Driver with PWM | eBay. Dorky found these shields here that they are using on the jarduino led controller. Power LED Shield : Chester's Garage. These shields will drive 4 strings of led's and are stackable for more strings. You can use buckpuck drivers like these BuckPuck - LED Supply.com, but you are limited to how many led's these will run. I think they will run 6-8 high power crees. So there are a few options.
That's prolly all the led lookup I'll be doing for a while lol. I got my waveline motors in. They are a 3 phase brushless DC motor with a hall effect sensor (like an older cdrom drive), so driving them is a little bit trickier than your standard DC motor. You can either use a ESC (electronic speed controller) or there are motor shields that will drive them. One in particular is the megamoto driver. ESC's are used a lot in the RC hobby and they make some 24 volt ones for hobby airplanes. I'm leaning toward the megamoto shields. I ordered a regular small (450 gph) dc pump that's actually built for a pond pump. After looking into it and talking to the owners they say it can be run in fresh or salt water. I'll run my feed to the pellet reactor/skimmer with it. It'll be nice to be able to control the flow via the pump and not a valve.
I got a ph shield ordered from andrew that ill run with my dosing arduino. I'm trying to distribute these shields around. As all the arduino's will be able to communicate with each other it really won't matter where the shields are located. I'll monitor PH with the dosing pumps since I will be dosing Kalk. So for now I'm stuck at work. Can't wait to get home and check out the new pumps but it'll be a couple weeks yet :(
That's prolly all the led lookup I'll be doing for a while lol. I got my waveline motors in. They are a 3 phase brushless DC motor with a hall effect sensor (like an older cdrom drive), so driving them is a little bit trickier than your standard DC motor. You can either use a ESC (electronic speed controller) or there are motor shields that will drive them. One in particular is the megamoto driver. ESC's are used a lot in the RC hobby and they make some 24 volt ones for hobby airplanes. I'm leaning toward the megamoto shields. I ordered a regular small (450 gph) dc pump that's actually built for a pond pump. After looking into it and talking to the owners they say it can be run in fresh or salt water. I'll run my feed to the pellet reactor/skimmer with it. It'll be nice to be able to control the flow via the pump and not a valve.
I got a ph shield ordered from andrew that ill run with my dosing arduino. I'm trying to distribute these shields around. As all the arduino's will be able to communicate with each other it really won't matter where the shields are located. I'll monitor PH with the dosing pumps since I will be dosing Kalk. So for now I'm stuck at work. Can't wait to get home and check out the new pumps but it'll be a couple weeks yet :(
Fishyj
Well-Known Member
I know this works, so maybe it will help you out. https://sites.google.com/site/caddnima/myreeftank/led_controller
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