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Old 25-02-2018, 02:05 PM   #11
justintime2001
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So a 2 amp 24 w version would do just fine then?

Is this diagram correct for set-up? Thanks.
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Old 25-02-2018, 02:07 PM   #12
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Yes, if you want 8 separate outputs.
Do you need 8? What are you going to be feeding??

Another thing to ensure is the Negative return wire. This has to carry the full 8.0Amps minimum so it should be 32/0.2mm wire at least.
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Old 25-02-2018, 02:11 PM   #13
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Quote:
Originally Posted by Flashbang View Post
Yes, if you want 8 separate outputs.
Do you need 8? What are you going to be feeding??

Another thing to ensure is the Negative return wire. This has to carry the full 8.0Amps minimum so it should be 32/0.2mm wire at least.
It will feed 10 street lamps at one end of the layout. Also 8 x station lights, 4 x double work yard lights, 10 x buffer stop lights and maybe lighting in a few buildings. All 12v LED's.
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Old 25-02-2018, 02:42 PM   #14
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FB beat me to it while I was walking the hound.

He makes a good point where only LED lighting is used - in my case I have a mix of lighting across the layout so I have one 1 amp feed to the GoW lights on platform 1, another for platform 2, another for the yard lamps and so on and so forth. Works for my set up.
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Old 25-02-2018, 02:47 PM   #15
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Quote:
Originally Posted by Steve M View Post
FB beat me to it while I was walking the hound.

He makes a good point where only LED lighting is used - in my case I have a mix of lighting across the layout so I have one 1 amp feed to the GoW lights on platform 1, another for platform 2, another for the yard lamps and so on and so forth. Works for my set up.
Would I be ok to just run a separate bus for the lighting using a 2A Convert AC 110-240V to DC 12V Power Supply and then just use droppers for the various light sections? Each section having a 1amp auto reset fuse for protection.
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Old 25-02-2018, 02:50 PM   #16
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Quote:
Originally Posted by justintime2001 View Post
It will feed 10 street lamps at one end of the layout. Also 8 x station lights, 4 x double work yard lights, 10 x buffer stop lights and maybe lighting in a few buildings. All 12v LED's.
You should do the maths ... Assume 15 milliamp (0.015A) per lit LED (Actually likely to be less at around 10ma or 0.01A)

At 15ma per lit LED then... 10 x 15 = 150. 8 x 15 = 120. 4 x 2 x 15 = 120. 10 x 15 = 150. Total at 15 milliamp per lit LED is 540 ma or just over 1/2 Amp!!

At 10ma per lit LED then ... 10 x 10 = 100. 8 x 10 = 80. 4 x 2 x 10 = 80. 10 x 10 = 100. Total lit at 10ma each is therefore 360 milliamp or 0.36Amp just over 1/3 of an Amp!!

Therefore an 8.0Amp power supply which is 8000 milliamp is vastly OTT!
Even the 2Amp one I suggested in Post #7 will be more than adequate with plenty to spare later if ever needed.
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Old 25-02-2018, 02:52 PM   #17
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Quote:
Originally Posted by justintime2001 View Post
Would I be ok to just run a separate bus for the lighting using a 2A Convert AC 110-240V to DC 12V Power Supply and then just use droppers for the various light sections? Each section having a 1amp auto reset fuse for protection.
That is the best way.
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Old 25-02-2018, 03:01 PM   #18
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Quote:
Originally Posted by Flashbang View Post
That is the best way.
Thank you. I have ordered the fuses and psu you suggested and will run a separate lighting bus. As for doing the math, that's easy for you to say lol. I don't know the first thing about watts, amps or volts. If it wasn't for this forum I'd be totally in the dark Thanks once again for coming to my rescue folks.
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Old 25-02-2018, 03:06 PM   #19
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Suggested basic wiring method with two separate feeds one negative return.
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Old 25-02-2018, 03:55 PM   #20
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Quote:
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Suggested basic wiring method with two separate feeds one negative return.
That's brilliant, thank you Fb.
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