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This is absurdly simple circuitry... as in, none really. I couldn't find a better place to ask this question, though  The right channel of my headphones(Sennheiser HD-555) quit working. I disassembled them and looked at all the solder points and everything seems OK and connected properly, but without a multimeter I can't be sure. Would it be possible for the driver to fail or is this problem almost guaranteed to be caused by a short? Drivers are pretty simple, just an electromagnet on one side of the cone and an earth magnet on the other side(right?) so I can't really see what would fail...
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Nov 29, 2011 02:36
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ashgromnies posted:This is absurdly simple circuitry... as in, none really. I couldn't find a better place to ask this question, though More likely caused by an open in the cord. Those things get bent, stepped on, chewed on, etc, and are pretty flimsy. Without a multimeter, you're guessing, though.
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Nov 29, 2011 02:55
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ashgromnies posted:This is absurdly simple circuitry... as in, none really. I couldn't find a better place to ask this question, though If you've already got it open and have a DMM you could measure the resistance from the driver to the plug, or you could just assume it's the plug and get a new one to solder on.
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Nov 29, 2011 11:53
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I'm trying to create an LED panel with 12 LED lights. I've had to learn a ton in the past week but I think I have it figured it out, but I would still like some advice in case I'm about to kill $140 worth of LEDs. I need a total of at least 3000 lumens, so I selected LEDs that provide 315 lumens at 350 mA. The max current they can handle is 1000 mA. Now I know that current drivers prevent LEDs from using too much current and burning out, however rather than more than double my costs by getting current drivers, I selected a 12 VDC, 4.17 A power supply. Now if I wire all these LEDs in parallel, the total amperage comes to 4.2 A. I know they will end up being slightly dimmer as a result of exceeding the available current, but that's OK (unless it's not, will that harm the power supply?). Will these LEDs be OK without a current driver if I'm supplying less than the total current requirements? Now, the other thing with these LEDs is that they have a forward voltage of 9.0V at 350 mA and 9.6V at 700 mA. I believe I read somewhere that I want to provide enough voltage to meet the forward voltage, plus two Volts, so my 12 V power supply should do the trick. So are all my assumptions and reasoning OK with all of this?
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Nov 29, 2011 17:48
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Hidden Under a Hat posted:I'm trying to create an LED panel with 12 LED lights. I've had to learn a ton in the past week but I think I have it figured it out, but I would still like some advice in case I'm about to kill $140 worth of LEDs. I need a total of at least 3000 lumens, so I selected LEDs that provide 315 lumens at 350 mA. The max current they can handle is 1000 mA. Now I know that current drivers prevent LEDs from using too much current and burning out, however rather than more than double my costs by getting current drivers, I selected a 12 VDC, 4.17 A power supply. Now if I wire all these LEDs in parallel, the total amperage comes to 4.2 A. I know they will end up being slightly dimmer as a result of exceeding the available current, but that's OK (unless it's not, will that harm the power supply?). Will these LEDs be OK without a current driver if I'm supplying less than the total current requirements? Now, the other thing with these LEDs is that they have a forward voltage of 9.0V at 350 mA and 9.6V at 700 mA. I believe I read somewhere that I want to provide enough voltage to meet the forward voltage, plus two Volts, so my 12 V power supply should do the trick. So are all my assumptions and reasoning OK with all of this? You've created a pretty nasty edge case - I would be pretty nervous plugging it in as it wouldn't work in an ideal world, and you're basically relying on nonideal characteristics of your LEDs and power supply to keep things from smoking out on you (and this is certainly no guarantee). I'm guessing if you plugged it in and powered it up, your LEDs are going to draw a tremendous amount of current. You claim the forward voltage is 9.6V at 700mA. That means if you apply 12V, you should draw more than 700mA. Even so, using 700mA with 12 LEDs gives a total current draw of 8.4A. Drawing 2x what the supply can provide will either blow the supply up, or make the voltage sag. There is a chance it will sag into a safe spot for the LEDs and continue running there indefinitely, but I sure as hell wouldn't count on it. Usually you put some sort of constant current source or current limiting resistor or something to control LEDs. 12V-9V = 3V drop across a theoretical current limiting resistor, giving a resistance of 8.6 ohms at 350 mA. This resistor is burning 1W, so you will need special resistors for that but it's within the realm of possible. Do you have datasheets/part numbers for these parts?
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Nov 29, 2011 18:03
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Okay, so I'm not sure if this is the best place to post this, but just jostle me a bit if it's not and point me to a better location. I have an old Panasonic window air conditioner unit. While it does a great job of cooling, it does a terrible job of turning itself on and off. The basic (1-10) thermostat control works, it's just awful at actually determining when to turn on and off. It's nowhere near as sensitive as it needs to be. Thus it will cool the room to 60F, and then let it heat up to 80F. Moving on to the point of this post, I had the brilliant/awful idea to use an Arduino with a temperature sensor to bypass the unit's own thermostat. I took off the front plate of the unit, and the controls seem to all be in AC, which means I can't simply just wire it to the Arduino directly. Now, I know very little about electronics besides the reading I've been doing recently. What would the best solution for this be? Should I abandon controlling the unit electronically, and go for a more manual approach (with motors)? What would be the best way to handle that approach?
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Nov 29, 2011 18:56
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Does it plug into standard 120VAC? If so, http://www.ebay.com/itm/RANCO-ETC-111000-DIGITAL-TEMPERATURE-CONTROL-120-240V-/120586443603?pt=LH_DefaultDomain_0&hash=item1c13831b53#ht_2239wt_1199 That unit is hugely popular with home brewers controlling their fridges, but will operate in both heat or cooling mode. It requires no modification of the device it is controlling. All you do is put that thing in between the wall outlet and the device being controlled as if it were an extension cord/surge protector, stick its temperature sensor wherever you want, and set the desired temp and swing. When the sensed temp gets down to setting - swing, it'll turn on power to the device and run it until the sensed temp gets to setting + swing. Or the opposite if you're in cooling mode. You will have to do a very little bit of wiring with that unit, but we're talking literally "cut an extension cord in half and plug the wires into a few screw terminals as per the very clear included instructions." No soldering, nothing funny, really anyone can do it. My dad did it solo and he sometimes has trouble finding his email. He's using his to control a heater in his crawlspace to keep some pipes from freezing in the winter. I use mine to control a freezer for storing kegs. Granted, it's $50, but it's an extremely rock-solid solution and you can take it with you when you ditch the old AC unit, since it literally just acts as an extension cord for the device. Put it on your fridge and have precise digital control if you want. Really, it'll work with just about anything, and there are wiring diagrams for most any application. And definitely get it from that patriot supply place on ebay, they're good people. Good customer service, and a fair price. Bad Munki fucked around with this message at 19:07 on Nov 29, 2011 |
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Nov 29, 2011 19:04
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We use the same Ranco unit to control a fridge we modified into a burn-in chamber. Works great, absolutely no complaints or regrets.
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Nov 29, 2011 19:09
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Literally the only problem I've ever seen someone have was when one guy had one controlling his fridge in his basement and said basement flooded, and the water got in his unit and shorted it out. Which is hardly an issue with the device itself. 
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Nov 29, 2011 19:14
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Cool Matty posted:Okay, so I'm not sure if this is the best place to post this, but just jostle me a bit if it's not and point me to a better location. If I were doing it I'd have a binary output that goes to 1 when I want it to come on and 0 when its off. Hook the binary out to a 120V relay rated for more than the amperage of the unit. If the arduino cant source enough power from an out to latch a relay, use a power transistor in between. Then hook the larger side of the relay to the hot wire on your AC. Donezo. Be sure to code in some hysteresis or a time delay in your controller or it will be shutting on and off ever few seconds. e: Go with the ranco unit. You will spend twice that on parts doing it my way. Besides that's likely exactly what the Ranco unit is, just premade. Cosmik Debris fucked around with this message at 19:29 on Nov 29, 2011 |
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Nov 29, 2011 19:26
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Delta-Wye posted:You've created a pretty nasty edge case - I would be pretty nervous plugging it in as it wouldn't work in an ideal world, and you're basically relying on nonideal characteristics of your LEDs and power supply to keep things from smoking out on you (and this is certainly no guarantee). The power supply is part number 7009K83 at McMaster-Carr (http://www.mcmaster.com/#standard-dc-power-supplies/=f5bs9j). The LEDs are here: http://www.ledsupply.com/07007-pw750-n.php So should I try to find a 9 V power source so that the LEDs are never trying to pull more than 350 mA? You say I would need a special resistor. What's the best way to do this so I wouldn't need that? LUXDrive has current drivers at 350 mA, are those essentially the same thing as resistors or would the fact that they have to burn 1 W of power not be as big an issue with those? I appreciate the reply and the information.
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Nov 29, 2011 20:20
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Hidden Under a Hat posted:The power supply is part number 7009K83 at McMaster-Carr (http://www.mcmaster.com/#standard-dc-power-supplies/=f5bs9j). The LEDs are here: http://www.ledsupply.com/07007-pw750-n.php Interestingly enough: quote:Also known as DC power supplies, these transformers conveniently install on a 35 mm DIN rail. An overload protection feature decreases output voltage and automatically resets when the output current returns to the rated range. All have a green LED output indicating light and screw terminal input/output connections. So it sounds like the power supply might go into constant current mode when it's overloaded, which would be perfect. That said, looking at the LED's datasheet, they hit 1A at 3.4V individually, or 10.2V in total for each unit, so driving it at 12V isn't a great idea. You can get a 1 or 2W resistor with a value close to 8.5-8.7 for each LED, and that will limit the current. Something like this may be appropriate: Vishay Metal Film Resistor
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Nov 29, 2011 21:05
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Delta-Wye posted:Interestingly enough: I thought about using these: http://www.ledsupply.com/0a009-d-v-1400.php The 12 LEDs are going to be arranged in groups of 4, so one of these 1400 mA drivers on each grouping of four LEDs would ensure that each is only getting 350 mA. Would that work? However, it would still be drawing 4.2 A total from the power supply which is only rated at 4.17 A. What would be the result of that due to the overload protection? Would that power supply drop the voltage slightly in order to slightly increase the available current? If it only needs an extra 30 mA, I think I would be ok running the power supply slightly overloaded if the voltage would simply be slightly decreased since the supplied voltage is overkill anyway. Are current drivers better able to handle the waste power that results from the extra 3 volts than resistors?
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Nov 29, 2011 21:50
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Bad Munki posted:Does it plug into standard 120VAC? While I'm a bit sad I won't find a use for my Arduino, this sounds like far too simple of a solution to ignore. Thanks!
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Nov 29, 2011 22:18
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You'll really be happy you went this route. Besides, there's always another use for an arduino. Like, having your doorbell tweet or something.  I love my arduinos
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Nov 29, 2011 22:29
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After much more researching, I've come up with the following wiring scheme for my LED array in order to get the desired lumen output for the best price:code:B = 1400 mA current driver: http://www.ledsupply.com/0a009-d-v-1400.php X = Cree XPG cool-white: http://www.ledsupply.com/creexpg-w139.php So, if I have this correct, each branch is getting 24 V and 0.65 A. With 7 LEDs in series, at 3.2 V / 700 mA, that is 22.4 V being used in each branch. The BuckBlock prevents more than 1400 mA from being drawn, or 700 mA per branch. Now, since 1.35 A is being supplied, but 1400 mA will be pulled, the power supply with be slightly overloaded, however the description says it has protection and will decrease output voltage to meet current demands. Since there is 1.6 V to spare in this arrangement, that means the power supply can afford to output 22.4 V in order to supply that extra 500 mA. If this is incorrect or a bad idea, I can go up to a 24 VDC, 2.1 A power supply, however the BuckBlock will then be trying to burn off an extra 700 mA. Is that OK? Am I just totally off base with all of this?
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Nov 29, 2011 23:44
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Hidden Under a Hat posted:Am I just totally off base with all of this? V = IR Hidden Under a Hat posted:If this is incorrect or a bad idea, I can go up to a 24 VDC, 2.1 A power supply, however the BuckBlock will then be trying to burn off an extra 700 mA. Is that OK? Am I just totally off base with all of this? I looked through the datasheet for the buckblock. It didn't have a schematic, but it seemed to be an efficient switch mode supply of some sort. It doesn't work like a resistive load (which would be 'absorbing' excess voltage), from what I gathered it turns on and off rapidly (far too fast for your eyes to detect) in order to get the correct average current. If you want the dimming ability, the buckblock isn't a bad idea. Hidden Under a Hat posted:
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Nov 29, 2011 23:58
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Delta-Wye posted:Yes. For the DC supplies, if the drawn current is below the rated current, they are in constant voltage mode. The provide the rated voltage to the load, and the load determines the current according to Ohm's law (for your circuit, at any rate). What if I put a 700 mA BuckPuck on each branch before the LED series instead of one 1400 mA before the branch? It would only cost a little bit more.
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Nov 30, 2011 00:13
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Hidden Under a Hat posted:What if I put a 700 mA BuckPuck on each branch before the LED series instead of one 1400 mA before the branch? It would only cost a little bit more. That is the typical way to do multiple strings of LEDs. I think you have gradually morphed your design into a standard configuration.
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Nov 30, 2011 00:14
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Hidden Under a Hat posted:What if I put a 700 mA BuckPuck on each branch before the LED series instead of one 1400 mA before the branch? It would only cost a little bit more. If you're going this way, not get one that runs directly off of AC? http://www.ledsupply.com/lt-901018700p.php http://www.ledsupply.com/xi-led120a0700c24f.php Just glanced through their products and picked the first two that looked promising. EDIT: The Xitanium model is much less than 1/2 the cost of the DC supply, saving you money! Huzzah.
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Nov 30, 2011 00:18
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longview posted:If the cords isn't physically damaged then it's almost definitely the plug, those things fail constantly. Alright, I actually just ordered a new cord assembly because it was only $5 and I'd rather have something that looks decent than the electric-tape-wrapped mess I'd come up with. Still no multimeter(asked a coworker to borrow one) but I wiggled the cable around a lot and wasn't able to ever get the right channel to even flicker on. Sounds like it may be the plug. Thanks!
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Nov 30, 2011 00:21
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Bad Munki posted:You'll really be happy you went this route. Besides, there's always another use for an arduino. Like, having your doorbell tweet or something. Make a couple of LEDs blink and submit it to hackaday
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Nov 30, 2011 04:00
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Okay, but they have to tweet each time they blink.
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Nov 30, 2011 04:06
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Bad Munki posted:Okay, but they have to tweet each time they blink. Yeah and give it an Internet hipster name like Atari Punk Console and you'll be golden.
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Nov 30, 2011 05:39
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Quick question about rectifiers: Say you have a transformer with 15VAC output (I'm guessing this is the RMS voltage?). How do you calculate the rectified DC voltage? I've looked at a dozen explanations, and they seem to contradict each other. Is it AC*1.41, AC/1.41, AC*0.9, some involve Pi or sqrt(2), are those AC figures peak or RMS, etc.... Wherever I look I get a completely different answer.
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Nov 30, 2011 12:46
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Sweevo posted:Quick question about rectifiers: A transformer's voltage rating pretty much always refers to its rms voltage, so the peak voltage is 1.41*Vrms. The voltage you get out of the rectifier will depend on the rectifier type and the diode type. For a full bridge rectifier with normal diodes you can expect to lose about 1.4V. So with 15VAC in, your peak DC output will be near 19.75V.
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Nov 30, 2011 14:24
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Sweevo posted:Quick question about rectifiers: As ANIME posted your standard voltage will be about 19-20V depending on the rectifier (Schottky rectifier will have a lower drop, for example) but 1.4V is the most common. The reason you've probably seen AC*0.9 is because your AC mains are typically specified at +-10% so your circuit has to allow for a 10% drop in input (and therefore output voltage from the transformer). If we assume a 10% drop your peak-value is 19V and that leaves 17.7V post rectifier, so you have to make the circuit work in that case as well. Based on that I wouldn't try getting much more than 15V DC from it, especially if you need a regulated supply.
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Nov 30, 2011 15:02
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Reading through an LED aquarium lighting tutorial, I see he says that a BuckPuck requires 2V to function... is this true? I can't find where it states this in the documentation of the 700 mA BuckPuck I want to use: http://www.ledsupply.com/03023-d-n-700.php If it does require 2 V, it kind of fucks up my array, since I was planning on having 7 LEDs running in series with a 700 mA BuckPuck off a 24 VDC power supply. That puts me at 24.4 V if the BuckPuck needs 2 V itself. Can anyone confirm this?
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Nov 30, 2011 15:28
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Hidden Under a Hat posted:Reading through an LED aquarium lighting tutorial, I see he says that a BuckPuck requires 2V to function... is this true? I can't find where it states this in the documentation of the 700 mA BuckPuck I want to use: http://www.ledsupply.com/03023-d-n-700.php Well it says the input voltage range is 5-32V You shouldn't look at the BuckPuck as something that consumes voltage before your LEDs. The whole point of the device is that it uses some magic (based on the name, most likely a buck/boost converter) to generate a voltage across the LED+/LED- outputs that will cause the desired current.
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Nov 30, 2011 16:11
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SintaxError posted:Well it says the input voltage range is 5-32V This is what he says: quote:Each buckpuck can handle 32 volts of DC power. Each white LED uses 3.3 volts when driven at 1000mA. Each royal blue He makes it sound like it does consume voltage which is why I was confused. But anyway, am I going to be ok running one 700 mA BuckPuck and 7 3.2 V LEDs off of a 24 V power supply?
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Nov 30, 2011 16:17
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SintaxError posted:Well it says the input voltage range is 5-32V Actually, you should look at it this way, in a sense. The converter is going to be regulating the current through the load, but it simultaneously has limits on the voltages it will output while in regulation. In this case, the max is (Vin-2V), in addition to the min/max on the input voltage. More below. Hidden Under a Hat posted:He makes it sound like it does consume voltage which is why I was confused. But anyway, am I going to be ok running one 700 mA BuckPuck and 7 3.2 V LEDs off of a 24 V power supply? He's right, it *will* be consuming current, and thus there will be a voltage drop. My memory of buck regulators is fuzzy, and I don't remember ever doing current-output ones (at least not intentionally, math-wise), so I can only guess at the internal topology. Regardless, this regulator is going to be taking your input voltage and applying an output across the LED load, which it attempts to regulate at the set current. I could try to talk about efficiencies and regulator dropouts, but I'm not Delta-Wye (as I am exceptionally lazy). Instead, think of it this way: The regulator has a minimum of 5VDC input. However, it requires approx. ~2V of headroom, which means that the maximum voltage it will be able to output is about 3V. BUT WAIT--ISN'T IT REGULATING CURRENT!?! It is, but let's look at a a Luxeon I red LED, for instance. The max current is like 385mA, and the forward voltage is 2.95V (for the max current, I presume). So, if you have a 350mA regulator/driver, it will push 350mA through the LED, and the voltage across it will be at most 2.95V. Which means supply the minimum voltage to the unit, 5V, would actually probably be ideal, since it's still within the voltage margin of 2V, and you'll get the best efficiency with the lowest input voltage you can get away with. As for your question: 24V is probably not enough for 7 LEDs, since you've passed the 2V margin. So, either bump it up at least another half a volt, or lose an LED. However, I gotta ask--you are using 700mA rated LEDs, right? Slanderer fucked around with this message at 17:13 on Nov 30, 2011 |
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Nov 30, 2011 17:08
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Slanderer posted:Actually, you should look at it this way, in a sense. The converter is going to be regulating the current through the load, but it simultaneously has limits on the voltages it will output while in regulation. In this case, the max is (Vin-2V), in addition to the min/max on the input voltage. More below. I'm using these: http://www.ledsupply.com/creexpg-w139.php. These are rated for 700 mA right?
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Nov 30, 2011 17:50
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Hidden Under a Hat posted:I'm using these: http://www.ledsupply.com/creexpg-w139.php. These are rated for 700 mA right? Up to 1500mA, apparently. However, the numbers are slightly different for the input current, seeing the datasheet. The IV curve shows a forward voltage of closer to 3.25V at 750mA, which means that you now need closer to a 25V input to power 7 of these in series. Another check: you are using this exact LED, not a different color, right? The forward voltage will vary with color.
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Nov 30, 2011 18:14
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Hidden Under a Hat posted:I'm using these: http://www.ledsupply.com/creexpg-w139.php. These are rated for 700 mA right? Yeah, it's an unusually high value for an LED, but you have selected unusual LEDs so it's alright. quote:I could try to talk about efficiencies and regulator dropouts, but I'm not Delta-Wye (as I am exceptionally lazy). Hidden Under a Hat: Have you looked at the AC-input current supplies? It would totally remove the need for a DC power supply and constant current supplies, and they looked quite a bit cheaper than the combined rig.
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Nov 30, 2011 18:19
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Delta-Wye posted:Yeah, it's an unusually high value for an LED, but you have selected unusual LEDs so it's alright. I'm using a PWM controller and from what I've read the PWM controller needs to be upstream of the current driver and since the PWN controller is DC input only, I can't use a combined AC-input DC power supply + current driver. Am I wrong that the controller needs to be upstream of the current driver?
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Nov 30, 2011 21:00
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Hidden Under a Hat posted:I'm using a PWM controller and from what I've read the PWM controller needs to be upstream of the current driver and since the PWN controller is DC input only, I can't use a combined AC-input DC power supply + current driver. Am I wrong that the controller needs to be upstream of the current driver? Uh, this PWM business is news to me. What is the PWM controller for? Brightness control? What kind of PWM controller? Part #, etc, etc. The buckpuck provides dimming and stuff onboard, I didn't read too carefully but it looked like it could be controlled with a simple potentiometer.
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Nov 30, 2011 21:04
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Delta-Wye posted:Uh, this PWM business is news to me. What is the PWM controller for? Brightness control? What kind of PWM controller? Part #, etc, etc. PWM is vastly more efficient than a potentiometer. e: I feel like you know that. Maybe I'm misreading your question? Cosmik Debris fucked around with this message at 21:09 on Nov 30, 2011 |
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Nov 30, 2011 21:07
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Cosmik Debris posted:PWM is vastly more efficient than a potentiometer. Great post! So, let's say the potentiometer wasn't directly controlling the current, but rather, controlling the behavior of the PWM... Like the product we are discussing? http://www.ledsupply.com/buckpuck.php EDIT: Way too snarky, ha. Look at the product page though. It provides +5Vdc and takes on 0-5V to control current for the dimming versions. Like I said, I didn't really dig into the product that much, but I'm guessing a simple pot will allow for control of the buckpuck, making the PWM stuff unnecessary, unless I'm missing something. Hidden Under a Hat: I think it would be great to get 'the big picture' of this project, rather than little pieces one-at-a-time. What are you building? EDIT2: Now that I'm thinking about it, I wonder how a constant-current supply will react to PWM - the load rapidly changes from LEDs to (close to) infinite resistance; I think this would make the CC supply go from a decent output to slamming the rail over and over again, but I guess it depends on how well it tracks the load and I still have no idea how it works internally. Does anyone have any guesses on what would happen? I'm thinking, considering it's constant current, this would be hard on it. Delta-Wye fucked around with this message at 21:23 on Nov 30, 2011 |
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Nov 30, 2011 21:10
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Delta-Wye posted:Uh, this PWM business is news to me. What is the PWM controller for? Brightness control? What kind of PWM controller? Part #, etc, etc. I have no idea what Hidden Under A Hat is doing but I've read that some current drivers from ledsupply provide a digital PWM input to supplement / replace the potentiometer (I haven't looked deeply into it). Aquarium hobbyists tend to use these to automatically simulate a sunrise or sunset with their LED arrays, typically providing the PWM from an Arduino 
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Nov 30, 2011 21:39
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Delta-Wye posted:Great post! So, let's say the potentiometer wasn't directly controlling the current, but rather, controlling the behavior of the PWM... Like the product we are discussing? My project is basically to build a light array for a photobioreactor that can provide realistic day/night sinusoidal light patterns. I need to be able to control those patterns with software I've designed, therefore I'm interested in this PWM controller which has RS-232 interface and something we have already worked with in the lab for another project so I know it works on a smaller scale for controlling LED brightness and works with BuckPucks when the controller is between the DC power supply and the BuckPuck: http://www.controlanything.com/Relay/Device/PWM85 So the way I determined how many LEDs I would need was based on the absolute highest photon flux an outdoor photobioreactor would see from the sun on a clear day at noon at sea level. From there I've been trying to be as cost effective as possible about the circuit arrangement and lumen/$. I think I have a good, cheap arrangement planned with all the help I've gotten from here and from reading aquarium lighting tutorials. The arrangement so far involves two parallel series running off of 1 24 V, 2.1 A power supply, with each series having a 700 mA BuckPuck and 7 Cree XPG stars, each putting out 254 lumens at 700 mA. I've actually re-adjusted that to 6 LEDs per series based on learning that the BuckPucks use 2 V and the forward voltage at 700 mA would actually be 3.25, but 12 total LEDs still gets me comfortably above the max photon flux I'll need. This arrangement also gives me to flexibility to add a third series in parallel, since I'm only using 1400 mA of current and the power supply provides 2100 mA. But the critical part is being able to control the light intensity through my software. I know RapidLED has a daylight controller but unfortunately that isn't flexible enough for me. I need to able to simulate cloud cover, different times of year, etc on many photobioreactors without going to each daylight controller and entering in new values. The PWM controller gives me the choice of 256 discrete duty cycles and can control 8 separate light arrays. Sorry I didn't give more info about this sooner, and let me know if you need more info. And I really appreciate all the help I've been getting from you guys.
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Nov 30, 2011 21:46
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