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Old 25-02-2018, 09:37 AM   #1
justintime2001
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Default Lighting circuit transformer

I have seen this Hornby transformer for sale.
BRAND NEW HORNBY TRANSFORMER P9000W from TRAIN SET for R8250

Would this be suitable for creating a separate circuit just for my LED lighting.

Thanks
Ian
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Old 25-02-2018, 11:20 AM   #2
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I'm no expert but the output of that unit looks too high a voltage for LED lights. What voltage are your LED's? Have a look around for something else at the 12v mark while we wait for an expert to come along. R-
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Old 25-02-2018, 11:36 AM   #3
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I would agree with Roger as appears this is suitable for use with a CDU for operating points.

After seeing other posts on the forum i purchased one of these
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Old 25-02-2018, 11:50 AM   #4
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Iím no expert but the higher indicated voltage would need a more appropriate resistor rather than the usual recommendation for 12v and 0.5amp will soon run out of capacity (depending on how carried away with your lighting you get. )

As I have said before, itís very easy to end up with lots of these small transformers dotted around the bowels of a layout. I find it preferable to get a PSU rated at 12v 8amps and split the output into eight separate supplies protected by selfresetting 1amp fuses. Very safe, very inexpensive and more than enough power to share around.
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Old 25-02-2018, 01:32 PM   #5
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Quote:
Originally Posted by Steve M View Post
As I have said before, itís very easy to end up with lots of these small transformers dotted around the bowels of a layout. I find it preferable to get a PSU rated at 12v 8amps and split the output into eight separate supplies protected by selfresetting 1amp fuses. Very safe, very inexpensive and more than enough power to share around.
Thanks Steve, Would you be kind enough to point me in the right direction for these components so I don't get it wrong? Thanks, Ian.
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Old 25-02-2018, 01:30 PM   #6
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Thank you folks, advice very much appreciated.
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Old 25-02-2018, 01:40 PM   #7
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You need to be extremely careful when using high current output power supplies. As Steve suggests use 1.0Amp self resetting circuit breakers immediately after the power supplies output On an 8 Amp I would use 8 x 1.0Amp breakers. Maplin sell them item AK07H example... Link to Maplin CBs They are wired into the 12 volt Positive from the Power supply by linking one to the other on one tab and then each output is taken from each CBs unused tab.

To be honest you're highly unlikely to ever need anything nearing 8 Amps! 2.0Amp is possibly even too high where all LED lighting is used! There are plenty of 2.0Amp PSU available like this example.. Link 2 to 2.0Amp PSU this one includes a 2.1mm easy wiring connector.
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Old 25-02-2018, 01:45 PM   #8
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Quote:
Originally Posted by Flashbang View Post
You need to be extremely careful when using high current output power supplies. As Steve suggests use 1.0Amp self resetting circuit breakers immediately after the power supplies output On an 8 Amp I would use 8 x 1.0Amp breakers. Maplin sell them item AK07H example...
Thank you, I have ordered a few of those now. Just need to find a suitable PSU.
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Old 25-02-2018, 01:50 PM   #9
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Would something like this do the job? 12V 8A AC/DC Adapter Charger Power Supply for CCTV DVR Camera/ 5050 LED light

http://www.ebay.co.uk/itm/12V-8A-AC-...MAAOSw09xZ8Ewt
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Old 25-02-2018, 01:56 PM   #10
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Yes that is ideal for 8.0Amp output with a regulated 12 volt too. But ask yourself "Do I need 8 Amps?" I think the answer will be a clear...No!

As I say in post #7 above 2.0Amps is probably OTT for most users needs where LED lighting is used.

Just remember 8.0Amps is equal to 96 watts of power. That's more than most DCC systems ever provide and think of the heat just a 60Watt lamp produces!!
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