I want to add LED lighting and I want to be able to control it via my hand held throttle. Looking for the right DCC decoder to do that. I am thinking that a normal mobile decoder could be made to do that via using the F0, F1, F2, etc function to turn a relay on/off so that the relay could switch 12VDC power on/off to various circuits. Does this sound right? would the F0, F1 etc circuits that normally just drive one or two LEDs be able to operate a 12VDC relay? Is there any other DCC device that would be more suitable?.
any function output will drive up 100ma, roughly five led's you would be better off perhaps with a stationary decoder if there are no motors involved ?
Kick myself. I had a solution readily available and I forgot about them. I have some SMAIL Tortoise machines recovered from a prior layout. They are DCC addressable and each one controls two SPDT switches rated at 2A. I can use them to switch the DC power for the accessories on my layout as long as I keep the load on each circuit within the 2A limit.
TCS and Digitrax also make lightning only decoders. There may be others, but I have used a Digitrax TL4 years ago but I switched to TCS a while back using the FL2 and FL4. Nothing wrong with the Digitrax units, I just decided to shift all my decoders to TCS. I use them mainly for lighted cabooses and can slave the FL4 to the decoder in the locomotive so the caboose lights are on whenever the headlight is on. And also the running lights get the directionality from the locomotive decoder. I use the FL4's for groups of streetlights or interiors of buildings etc.
I saw the FL4 when I was looking around but they would use track power for lights and I did not want that. I would assume they could trigger a relay to get higher loads via a separate 12V source.
What you would want to do is to use the motor output on the decoder. If powering LEDs you would set the max voltage on the decoder to the max of the LEDs. That would allow you to actually dim the LEDs. You would pick a decoder based on the amp draw of the circuit.....you might need a large scale decoder. But it sounds like you have the solution already.
I did not want to use the power from the decoder to directly power my accessories. That would be using track power and I did not want that. I want the decoder to act as a relay so I could provide power from an alternate source.
If you google or search YouTube for stationary decoders there is one DIY system running around using an Adruino that has 15 outputs. I can't vouch for the output amperage but the video shows it running through a series of tests that has all 15 LEDs on at the same time.
I don't know of any decoders with built in relays, but if you use Geoff Bunza's DIY Arduino decoder you can operate up to 17 relays (sold separately).
The Geoff Bunza's decoder can be powered from track or an external source. The arduino can handle the leds. I don't know how much power you want to handle. Maybe you want something like this http://model-railroad-hobbyist.com/node/26583 the decoder trigers the tip120 which can handle more load. you can ask the author for details.
