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schoey

Nooob from Aus, LED's/Voltages/where to start?

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Hi all,

 

Looking to start work (from scratch) for 2014. I've got my head around the controller side of things, at least enough for now I think, I'll be going with 16-32 channels for starters - house and block are quite small so no real need to go too much bigger (for now ;)  ).

 

My biggest headache at the moment is working out LEDs,  in Australia we are on 240V we are also very restricted on DIY electrical unfortunately and we tend to be gouged on price in spite of being quite close to china which is where all this stuff comes from. So question time:

 

1) Silly question first off, but I can't see it in any specs, these LED's definitely run on A/C at the actual LED right? Meaning there is no transformer in line knocking it down to 12V DC? 

 

2) The easiest option for me is buy from an Aus distributer, however it's also likely the most expensive: http://www.mytbritelights.com.au/christmas-lights/m5-mini-lights/m5-christmas-lights-pure-white.html  70 string, M5, $25AUD. I assume these are suitable if I end up going this way?

 

3) Looking at Magic in the sky and equivalent string of 70 would be about $10.37US, so way cheaper but assuming the answer to question 1) was yes than I've got a voltage problem. Any ideas if these can handle 240V? Step downs on every channel would quickly cancel any savings. 

 

4) Anyone looked into Chinese suppliers direct or via focalprice/aliexpress/dhgate? Something like http://www.aliexpress.com/item/Energy-Led-String-100-LED-10M-Fairy-Lights-Warterproof-IP44-Christmas-Garden-Outdoor-Indoor-lighting-200M/1358285751.html looks the goods as far as price goes -  $6.50US per 100 light string! Only worry with these is the 'controller box' setup they have wired for preset functions, if they still just pass through the full 240V I should be able to cut the box out and wire a plug directly, anyone have any experience with this type of LED? 

 

5) I know I said I had the controller side of things worked out, but one question would be about the kits, probably best to ask LOR direct but I'll see if anyone here knows. I'm keen on kit form (heaps of soldering experience, engineering background) but there isn't an Aus plug option there, I'm sure they'd offer it? Is the kit form worth it by the time you add box, leads etc?

 

 

I hope all that isn't expecting too much, I promise I've done heaps of searching and reading, but no luck finding answers to those Q's.

 

Thanks in advance!  :D

 

 

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Since I don't know, I'm not going to answer anything but what I do know...lol...not that much...lol. LED's are DC devices. They are in fact, Light Emitting Diodes and they run only on DC voltage. Each string has a rectifier which converts the AC to DC, filters it somehow then sends that power to the LED's along the path. There are different types of strings with quality/price, usually whether the LED's are half-wave or full-wave rectified. Half-wave rectified LED strings are cheaper but may not dim/fade properly. Getting your 240 down to 120 just needs a transformer however, I don't know about your frequency there? Here its 60hz. I know when I was stationed in the UK, it was 50hz which created issues for motors designed for 60hz. I'm guessing that electronics for the most part, has taken this into account.

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LED's are DC devices. They are in fact, Light Emitting Diodes and they run only on DC voltage. Each string has a rectifier which converts the AC to DC, filters it somehow then sends that power to the LED's along the path. There are different types of strings with quality/price, usually whether the LED's are half-wave or full-wave rectified. Half-wave rectified LED strings are cheaper but may not dim/fade properly. Getting your 240 down to 120 just needs a transformer however, I don't know about your frequency there? Here its 60hz. I know when I was stationed in the UK, it was 50hz which created issues for motors designed for 60hz. I'm guessing that electronics for the most part, has taken this into account.

 

 

Thanks, I thought that in the back of my mind (about the DC voltage) I just looked at so many descriptions on the different retailers sites that made no mention of anything but the AC voltage that I guessed they somehow worked on AC. Yes we're 50hz which can cause issues with some things but others seem ok.

 

So why not do the conversion at the controller ie AC in - multiple DC channels out? Seems that would cut out a lot of duplication in AC/DC transformers.

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If you are talking about an LOR controller, its putting out (16) 110/120 VAC signals, for here at least and truly, I don't know what they might sell for where you are. The individual strings are 110/120 for here again and the rectification is done in the string itself. Now if you went to RGB, a DC controller card with RGB strips, you would be running at 12VDC on the strip but you would still have to either transform the input AC from 220/240 down to 110/120 unless LOR has an option for the higher voltage. I really do not know if they do or account for this. When I was stationed in the UK, I had a 1200watt transformer for connecting my 110v devices. For the most part it worked just fine for me. I would imagine that's what you would need for the LOR controllers from here. Lots of devices such as computer power supplies have the selector switch on the back for picking up a different internal transformer coil winding just for this reason. I just now looked at the controller documentation and it says they have a 240VAC version available! Adapting 110/120 LED strings to 220/240, you'll have to go through a transformer. Sorry, its just the way it is. You could "hack" the strings, providing you knew the precise amount of current draw, used a rectifier, filter capacitor and either a load or shunt resistor to get to the specific voltage needed but truly, its probably cheaper to buy them already manufactured. I would think LED strings are available where you are therefore already set up for 220/240?


Oops, forgot to add above: The DC controller card will run RGB strings/strings/pixels and so on, but they require a power supply that puts out 12VDC and again, its input would need to be set up for your voltage there.

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The CTB16PC controllers CAN BE either 120VAC or 240VAC.  However, I don't believe LOR supplies the conversion plugs for the 240VAC systems, the end user has to purchase the adapters for their voltage requirements.   That's what I recall reading somewhere on the LOR Site when I first purchased my 4 controllers.   And if they are 120VAC when you get them, it only takes a small jumper to be removed from the 120VAC pins and put on the correct pins for 240VAC use.  Takes less than a minute to do, takes more time to open the box and find the jumper, that it does to move it!

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Hi

I'm from Brisbane Australia. I've been running LOR for 8-9 years. I started with the 240V AC controllers, but since the DC controllers were released, I have been using these more and more. Reasons are several, 

  1. Safety - having 240V strings in the display is potentially dangerous as the insulation is never as good as used on certified Australian electrical products.
  2. Costs - the DC boards are cheaper/channel even after factoring in the need for separate DC supplies. Usually a 350W DC supply will power at least 2 DC 16 channel boards. Low voltage cabling and connectors (speaker wire or security cable) is much cheaper and less bulky than 240V cable and connectors.
  3. The DC boards give a much better low load control on light strings.
  4. You can dispense with the bulky plug-packs and controllers that come with the Australian low voltage lights.

There is a bit more of a learning curve in going the DC route than the AC route, but it is well and truly worth this effort. There is also good support on the Australian Christmas Lighting forum even though this forum is heavily biased to RGB and pixel setups (which is good if you eventually decide to follow that route.) I personally have decided to use only a small amount of RGB lighting. 

http://auschristmaslighting.com/forums/index.php

 

Hope some of this helps.

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Thanks gents,

 

Heaps of extras there I hadn't really considered, I agree Geoff; DC may very well be the go here in Oz. I'm definitely just keen on LED's, the cost of RGB etc. just pushes it a bit far for me. I'll go and check the Oz forum for sure.

 

thanks again guys

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Advice from someone there is the best advice rather that trying to figure out what might or might not work from out here. Cool you found that resource!

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In the UK, 24V ac LED strings are plentiful (designed for use with a transformer for safety when used outside). The LOR controller will run on any ac voltage, and works happily on 24V from a largeish transformer.You have to do a bit of messing about with the right-hand half of the board, as it wants either 120V or 240V for the transformer that powers the electronics. With a bit of thought and modification, the right-hand half can use a 24V supply as well.  I have a 240V to 24V transformer supplying three of the standard LOR controllers.

 

Regards,

 

Alan.

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dgrant is correct that LED are a D.C. device, but they are still diodes and can be put across an A.C. source. This would give you what is known as a half wave string. Some of the nicer strings use a full wave rectifier and it is not as easy to see them flicker. But you do not want a string that has a filter, aka capacitor. These will mess with the ability to fade and shimmer. And over the past few years I have hear of a few guys saying that there string burnt into flames. And if you buy any of those strings with a multi function controller built into the string. Then use the controller only as full on or off, nothing between.

 

Alan, great hack..

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