I plan to run all my turnout AND signal decoders from an auxiliary track bus. By auxiliary I mean Rail A will be common for everything. Rail B power comes from the Digitrax BDL168 to each block. The aux bus will tap rail B at the booster, before it gets to the 168. I'll run the aux feed next to the main rail A feeder all around the layout. First, this will keep all the accessories, and their decoders, from messing with block detection. The 168 feeds just the rails, and the only things taking power from the rail are the locos and wheel sets. Second, since I'll have clean power virtually everywhere under the track, it's a snap to move or add a signal or turnout. And Third, I think this is a pretty cool way to do it. :shade: My current track plan calls for 19 turnouts and a minimum of 15 signals. I'm not worried about power for the accessories themselves. LEDs only draw a few mA, and it's my understanding that solenoid turnouts use only a few mA when they're idle. They need a quick surge to recharge, but as long as I have a small delay between multiple switches, it shouldn't be a big deal. So the question, how much current does a small decoder, like the TCS FL4, or the Digitrax DS51K1 need, just by itself? Times 34, and counting... :teeth:
Decoders don't use up much power. They won't be all operating at the same time. Stay cool and run steam.....
S/390, Welcome to Trainboard! There are some exceptions, notable among them are sound decoders, but most small decoders have an idle current in the 2 to 3 milliamp range.
I did this experiment several years ago to test the power requirements of my Lenz 100 system . I had 36 loco's on the layout with the front headlights on (each loco has a decoder). I had over 24 turnouts, 16 signals, four auto-reversing units and 25 DSX sound only decoders turned on as well. There were two 28 car trains each powered by a FT ABBA unit with lights turned on. The total amps used at rest were 1.14 amps. With the two trains running at 1/4 throttle the total amperage used was 1.27 amps. When the train speeds increased to 1/2 throttle speed, the total amperage used was only 1.53 amps. The Lenz 100 LZV command system is 5 amps. You have plenty of power to spare. Stay cool and run steam......
Thanks guys, that's what I figured. :thumbs_up: There was a thread on Digitrax groups, with an example of using an ATTiny chip to directly drive LEDs. This chip is designed primarily for battery powered mobile applications. It takes very little current, measured in micro amps. So it makes sense that things like the FL4 would only need a little juice. Just wanted to make sure.
