decoder strength

[controller]

Hi all, I have a hst 125 with control car, dummy car, and three coaches. I hope to add more coaches. I have the directional lights on the control and dummy cars working ok, but I would like to light the coaches using an extra decoder in the dummy car. Would one decoder be enough for four or more coaches, or would I need one for each coach?. I am using about six leds per coach.

 

Thanks, Controller.

[irishthump]

This will depend on how much current your LEDs draw and how much current your decoder function outputs can handle.

LEDs draw roughly 20ma each (that's a very general estimation, it varies depending on size, colour etc.) while decoder outputs will handle anything from around 100ma on the cheaper ones up to 250ma on the more expensive sound decoders. Even 3 coaches with 6 LEDs each, not to mention any directional lights in the dummy power car would quickly add up and probably overload the decoder's outputs.

You also have to consider how many amps your DCC system supplies to the track. Some more basic systems only put out 1 or 2 amps and like I said I rake of lit coaches can eat into this!

 

You could probably control 2-3 coaches comfortably with one decoder, but then you've also got wiring between the coaches which can be a pain. The ideal solution is a decoder for each coach, but this gets expensive even with function only decoders.

 

Personally I wouldn't bother with decoders at all, I'd have LEDs powered directly from the track pickups fitted with a flicker free circuit. You could also install a small switch in the underside of the coach to turn of the lights when not in use.