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Accessory Voltage Question
Daniel models in O scale and asks:
“In hooking up power to accessories, I was advised to setup four power lines, plus a ground. Make the lines 8,10,12 & 14. Then apply to them per each accessory. Problem is anything I reference gives a wide variance, like 9-14 , 10-12, etc. pretty confusing. Any advice is appreciated.”
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If something says it needs a voltage of 9-14, 10-12, etc. it refers to the minimum and maximum voltages for the item to work. Most power supplies are not very precise; a 12 volt supply may be off by as much as a volt in either direction. So, if your accessories are all in the 9 to 14 volt range, a decent 12 volt supply should be fine – as long as it has the amperage to run the number of accessories you have. If you have some 9 volt accessories and some 12 volt accessories, you will probably need separate power lines and supplies for them.
I have used a 5 volt supply for all my odds and ends as far as lights go. On some of them I have used resistors to cut the voltage to less for LED’s which run from 1 1/2 to 3 volts. You could try using a 16 volt supply in case you need anything that high and use resistors to cut it for lower voltage items. Remember LED’s and some electronic accessories use DC and you might have to use some diodes to change from AC.
What I have done is use a single power supply and then voltage regulators to step down the voltage where necessary. A search on eBay for ‘buck regulator’ will bring up any number of very cheap units which have a good current rating. The only thing you then need to ensure is that your power supply has a sufficient current rating (in amps) to cope with the draw from all the items connected to it.
One caveat – many of the cheapest buck regulators are sent direct from China. In my experience, this does not present any issue regarding quality (and, anyway, any sold by local dealers are sourced from China but just cost a bit more) but given the situation regarding many countries’ international relations with China, trade sanctions etc. may make them more difficult to source than previously.
I model in HO but I know a lot of LED lighting is 3 volts. I bought an AA battery holder for 2 AA batteries, = 3 volts DC (LEDs require DC).
Then a simple SPST switch to turn then on and off.
Thanks to all who commented on my voltage question. A lot of help