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LED power question

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Old 07-09-2009, 9:44 AM   #1
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LED power question

I'm getting to the end of my home cinema project, and I'm currently looking at what to use to power the LEDs I'm using. Currently I'm using an xbox HD-DVD power adaptor, which outputs 12v at 3A. It's only a temporary/testing measure. I've worked out the total forward current of my array to be around 6A.

What would happen if I just connected it to one of the many 10-60VA transformers I have lying around? Would everything explode and all hell break loose?

I'm just not impressed with the prices of LED transformers I see, ones in screwfix and other places cost £15, when you can pick up the ones used in MR16 lighting for less than a fiver. Is this price difference justified by a genuine reason or is it just a way to rip off a niche market?

Failing that, is there a place anyone knows I can order LED transformers cheaply?

I asked this question in the other forum but was told it would be a better idea to ask here.

Thanks
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Old 07-09-2009, 1:34 PM   #2
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Re: LED power question

MR16 Transformers are 12V AC, and LED drivers are 12V DC.

£15 is not bad, and is probably a base price for non dimmable led drivers.
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Old 08-09-2009, 3:20 PM   #3
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Re: LED power question

I've used a 12v trigger to power LEDs before. Use the trigger for zone 2 power (where you aren't otherwise using the zone 2 capabilities of your amp) which would normally trigger a power amp. You therefore also have discrete on and off commands (zone 2 on/off) as well as the ability to have it automatically always be on whenever the system is on (zone 2 follow zone 1).
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Old 08-09-2009, 7:31 PM   #4
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Re: LED power question

that sounds really good, can you explain a bit more in detail how you would do that?
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Old 09-09-2009, 2:40 PM   #5
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Re: LED power question

Bit of trial and error but where the LED strips come out to basically two wires, you just gotta work out which is which and terminate to a 3.5mm mini-jack and shove it in the back of the amp. We did short the amp out once though so not for the feint of heart, but a lovely solution that effectively turns the zone 2 power button on the remote into a light-switch. Same princible works with anything 12v, I've used the 12v trigger out on a projector to power a 12v fan to cool it in it's ceiling box for example.
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Old 09-09-2009, 3:26 PM   #6
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Re: LED power question

Quote:
Originally Posted by Liam @ Prog AV View Post
Bit of trial and error but where the LED strips come out to basically two wires, you just gotta work out which is which and terminate to a 3.5mm mini-jack and shove it in the back of the amp. We did short the amp out once though so not for the feint of heart, but a lovely solution that effectively turns the zone 2 power button on the remote into a light-switch. Same princible works with anything 12v, I've used the 12v trigger out on a projector to power a 12v fan to cool it in it's ceiling box for example.

and the other wire goes to?
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Old 09-09-2009, 3:30 PM   #7
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Re: LED power question

Sorry meant three - ground, +ve, -ve
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Old 09-09-2009, 5:18 PM   #8
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Re: LED power question

i am totally lost now, lol
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