Railfan Technology > Signal wiring for switching signal aspects help

Looking for some help for wiring up a  RR signal that can be changed from 3 different aspects (Clear, Approach, Stop) using a rotary switch. I believe I found a good 10V DC power converter to drop the voltage for the 18 watt 10V DC bulbs. Just seeing if anyone has found a combination that works. 
Thanks in Advance, Jeff
 

What kind of signal head?  Three light or searchlight style?

 

I have a pair of PRR  (CPL) Red aspects also in one of the PRR lights  and a B&O CPL .  Two of the three are completely sandblasted and repainted. working on the 3rd one now.

Sorry, I'd forgotten to check back on this post.

I use a Mean Well LPV-60-12 (120VAC to 12VDC, 5A power supply) to power each of my signals.  They're cheap, efficient, and pretty reliable.  But if you've already got a beefy 10-12V supply that'll do 5A or so, that's probably good enough.

You probably won't find rotary switch that will handle the ~4A of direct current each head's aspect will draw (10-12V into two 20W bulbs will be roughly 4A with a higher inrush current).  You'll probably want to use the rotary switch to drive relays that actually switch the lights on and off.  I'd recommend just good ol' SPST (form 1A) automative relays.  (You can use form 2A or 1C as well.)  They're cheap, plentiful, handle good amounts of DC current, and operate on 12V.

Here's a sketch of kind of what I'm thinking - sorry, my hand-drawn schematics are messy at best any more, but it's what I could sketch out while I was in another meeting:




 



Edited 1 time(s). Last edit at 12/10/20 13:38 by NDHolmes.

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