Old Croc

WKDOR

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Just attending to my much-loved but very elderly Croc.

It has been happily powered by R/C battery in a trailing Postwagen via the lighting socket (Shock Horror) for the last few years, but I'm now moving all the controls on board into the main engine room. One reason is to get a constant lighting circuit.

Using the several previous disassembly/chipping threads on GSM and here, progress so far is good - I've removed all the track pickups and worked out the existing wiring. Now for the lighting. My Enhanced RailBoss controller provides:
[*] a directional constant voltage lighting circuit at battery voltage = 18.6v.(excl overcharge), and[*] a directional constant voltage lighting circuit at LED voltage and current and I now need to decide which way to go!

I had considered redoing the lighting circuit in series. Using the existing old-style 5v bulbs (and leaving aside RhB lighting complications), I have 4 (3 headlights and one cab) lights at 5v per bulb = 20 volts in each direction. But that will require a complete re-wire of the circuit with lots of connections x 2.

I have also wondered about salvaging most of the existing circuit, keeping the existing parallel design but replacing the bulbs with Champex Linden/FGB 19v replacements that are LEDs in the same screw socket format with resistors. Has anyone used these?

Or I could rip all the lighting circuits out and start over with straight LEDs. Attractive, but a lot of work to shoe-horn eight LEDs in.

Help please - what would you do?

Mike
 
Mike - I can't tell you what to do, but I can comment on how it would be done. The voltage output for the directional lighting would be used is you go with the 5V bulbs in series. The constant current output would be used with LEDs (not containing internal resistors). The LEDs could be placed in series up to the maximum number of voltage drops; i.e. each LED drops about 2V. You could string about 9 or 10 of them in series if you had 20V total available. If you use and LED with a built in dropping resistor, then you would use the voltage output.

The idea of the constant current output for LEDs is to make your wiring simpler; i.e. no external resistors or calculations needed.
 
Many Thanks Del I was hoping you'd chime in with good advice as ever. I'll take all you say on board b4 making my decision.

Has anybody here used the drop-in replacement LED screw in bulbs 19 v with resistor and polarity protection? Available from Champex Linden and FGB Berlin if I pay the shipping. Only place I can find online in UK is Conrad #51907 but it doesn't actually say that they're a straight swap for LGB.

Mike
 
Many Thanks Marc, that's very good to hear.

Can you say where you got yours please. And also if you've fitted them in traditional head lamps on locos where the fitting is at 90 degrees to the lamp, I'm a bit concerned that the LED ones look longer.

Best

Mike
 
Hello Mike,

Mine came from Champex Linden and from RD-Modellbahnen, respectively. I think they are all produced by Beli-Beco in Germany.

I use them in platform lamps and also for the interior lights in USA Trains cabeese.

If you like, I can put one in the mail for you to try. I have to order more from Champex Linden anyway. Just PM me your address.

Marc
 
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