Gunrunnerjohn question on your lighting regulator

I powered a 5 meter roll of them for 1-2 minutes with no ill effects.

Steve

It's not how many LED's it can support, it's how bright do you want them.  The lighting regulator will supply from around 5ma to 45ma constant current for lighting LED's.  It doesn't matter how many are out there, but you have to keep in mind that to light a number of cars with 45ma, the lights won't be that bright.  It was designed with a single car in mind, I hadn't considered lighting multiple cars with it.  I've had no problem lighting double-decker cars with it, but they're about 1 1/2 normal cars worth of lights.

Simple experiment:  Decide how long the total strip will be to equip all the cars you're wanting to power off one, cut a strip that length and hook it up to a lighting regulator.  See if they're bright enough.

Do all the rolls of LED lights use the same amount of power per inch? I have seem posts mention how some of the newer light rolls  have smaller LED's.

Thanks GUNRUNNERJOHN.

MARK

All the LED's are rated at 20ma maximum current each as a rule.  I almost exclusively use the 3528 size LED equipped rolls.  The rolls I use are typically rated at 2A max for the 300 LED's.  Since they have three LED's in series with the resistor for each group, that's 20ma at 3V for each LED.  The 5050 strips are actually the three-element LED chips, they have three chips in one package, and obviously are much brighter and also consume three times the power.

In any case, the actual "maximum power" means nothing really, it's how much light do you get for a specific input current that's key with my lighting regulators.

Doesn't the math say 20ma for each set of three ( 100 sets of three X 20ma = 2 amp)?

John H posted:

Doesn't the math say 20ma for each set of three ( 100 sets of three X 20ma = 2 amp)?

Read what I said again.

Since they have three LED's in series with the resistor for each group, that's 20ma at 3V for each LED.

Since they're in series, obviously the current has to flow through each one. However, each LED drops around 3 volts at 20ma.

Got it. Had trouble wrapping my brain around 20ma going through each resulting in 20ma for the trio. Thanks 

Where do you buy your rolls, it seems everyone now sells them? Do any have any advantages over the other when used in a conventional layout?

The LED rolls all have very similar characteristics, operating voltage 10-12 VDC.

First off, running conventional is a different kettle of fish.   My lighting regulators probably won't do the trick for conventional operation as they assume they're going to be supplied with at least 10 volts AC.  For conventional operation, it's sometimes a little trickier to get constant lighting.

I would look at one of the eBay Buck/Boost Regulator Modules with a bridge rectifier and filter cap in front.

Input Range 3.8V ~ 32V

Output Range š1.25V ~ 35V

Input Current 3A ( max ) , no-load 18mA (5V input , 8V output , no-load is less than 18mA.

 Boost Buck DC adjustable step up down Converter XL6009 Module, eBay: 112322868266

As GRJ says, for conventional operation consider an approach that can supply the necessary DC voltage (10-12V) irrespective of whether the incoming AC is below or above the target voltage.  You should be able to do this without with minimal soldering if that's an issue.  This is demonstrated in this how-to thread.

Should be less than $5 for the module, bridge-rectifier, capacitor, and inductor (if this would ever run on a DCS layout).

The module would be capable of driving the LED strips for 3 (or more) daisy-chained/tethered cars.

stan2004 posted:

You should be able to do this without soldering if that's an issue.  This is demonstrated in this how-to thread.

Stan, without soldering?  I see a number of soldered connections!

Darn!

I normally run 10 to 14 volts on the layout with 8-12 eighteen to twenty inch cars. The engines tend to need the higher volts being  Weaver E8 ABA or the big 4-8-4 steamers. How much will that change once I remove the 2-4 light bulbs in each car and run LED's?  I do have 3 PS2 or TMCC equipped engines now but normally run the conventional stuff because I have more of it. I'm a little new to changing up the wiring but willing to try it for the obvious benefits LED's gives. Will the Buck/Boost regulator work in both conventional and 18V . Or do I need to have dedicated cars for each system, which I would like to avoid.

Yep, the buck/boost solution would be for both environments.

I guess I meant component-level soldering.  I figure through-hole or wire-lead versions of the inductor (if needed for DCS), bridge rectifier, and capacitor could be assembled by twisting the leads and either wire-nuts or heatshrink to secure the mechanical connection.  But you're right - while there are DC-to-DC modules with screw-terminals (no soldering) I think the buck-boost versions require 4 solder connections.

Another idea.  If one 45 mA current-source can handle 1 1/2 cars, two Hennings modules in parallel should handle 3 cars.  Current sources can be put in parallel.

This is very true Stan, I never really thought about paralleling them.  As long as the AC inputs were not crossed between the two modules, everything should work out and you'd get the combined current capability.  90ma should light three cars pretty bright if my experience lighting 18" cars on 25-30ma is any reading.  This is 25ma from the lighting module, it's an MTH 18" car, and it's a pretty brightly lit room.  I actually crank the lights down just a bit from this, this was an early test of the lighting module.