Driver for multiple LED outdoor lights and LED strip

hairy1

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Topic # 109687 25-Sep-2012 10:47
Hey folks, I have recently done a bit of a project and put in some outdoor lights. All the cable is laid and I am running three halogen 50 watt MR16's on one cable from a 200 W 12 V AC Transformer. It all runs fine but I am wanting to run some LED strip lighting (which I already have) on the same circuit. The problem arises from the fact that the LED strip lighting doesn't like the 12 V AC. So, I need to find a driver that can run 3 x 5 Watt LED lights (I will swap the halogens out for LED's) and a 5 metre LED strip. I am having trouble finding something that is an LED driver but can run all this stuff off one circuit. The other thought I had was trying to convert the existing 12V AC to 12V DC. There doesn't seem to be anything around to do that. Any ideas? Thanks, Matt. Galaxy SIII, Galaxy Note 10.1, ASUS UX31e Ultrabook, Mysky HDi, 2talk

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Reply # 691267 25-Sep-2012 17:58
Have you been to an electrical wholesaler? This is something they will have on the shelf. Stewarts/Radcliffe's is my first choice but otherwise there is Ideal, Corys and some Mastertrades.

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Reply # 691329 25-Sep-2012 19:58
LEDs should require only a regulated 12V DC, not an constant current driver (unless you are making an LED fitting yourself). Where are you putting the transformer? You can never have enough Volvos!

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Reply # 691368 25-Sep-2012 21:25
Thanks for the replies guys. The transformer is in a garden shed and is on a relay. There is a run of abut 20 metres of 2.5 mm 12 volt cable. I haven't checked out the wholesaler yet but have been buying stuff from JA Russell. The three halogens are Mr 16's and I have a bodgy led mr16 from DX.com to try when I find a suitable transformer. I found a transformer at surplustronics Surplustronics I will whip down to JA Russell and see what they have to say....j Galaxy SIII, Galaxy Note 10.1, ASUS UX31e Ultrabook, Mysky HDi, 2talk

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Reply # 691812 26-Sep-2012 17:15
Looks like you need only about 20W, but going for an IP rated transformer is the right thing to do for a shed. A 60W transformer will be more than enough, also for future proofing. You can never have enough Volvos!

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Reply # 691815 26-Sep-2012 17:22
I think the 5 metres of LED is about 25 Watts, plus 3 x 5 W for the LED spots so the 60 Watt transformer should do the trick nicely. The guys at JA Russell looked at me blankly and said they would have to "get something in". They said "We have 12 Volt AC transformers if you want one of those". They are stuck in last decade methinks. Galaxy SIII, Galaxy Note 10.1, ASUS UX31e Ultrabook, Mysky HDi, 2talk

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Reply # 692312 27-Sep-2012 15:16
LED world had something that was like a transfromer but a switchmode protected legit approved 12v power supply. Problem is dimming has to be done after the power supply with a PWM dimmer so useless if you already have a nicely automated phase controlled dimming system. I am suprised there is no LED driver that will take in a phase control dimmed AC feed and output a PWM'ed 12v DC output. Would have thought there would be demand for that. Richard rich.ms