Large Scale Central

Car lamp capacitors

Electronics Power and Sound
#21

Dan, I run long trains on steep grades, and smoke and sound often with 2 to 4 speakers, and I let the trains run for hours, often leaving them running when I go to home depot, etc.

So track power is it for me, also, I hate having to permanently couple a trailing car to a small loco because there’s no room for batteries. I also like powerful smoke systems in steamers, which can consume 1.5 amps alone… I could not go battery without having to give these things up.

p.s. When you come out to San Diego, I’ll provide the cigars:

#22

If those cigars come in tubes, cut them and use them for pipe loads. Battery people could hide rechargeable AAA batteries in them!!

#23

Will do. My favorite are Onyx Reserve. Even though they are a Maduro, they are still pretty mild. And they don’t break the bank.

Thank you for the invitation. If you are ever in KC way, stop on by, sit by the fire and watch a few trains go round, and play some pinball.

#24

If I were to add a supercap, would I wire it in on the output side of the buckboard between the board and the bulbs across the two wires? Pos leg to pos wire and neg leg to neg wire?

I figure I can add a single 5.5v memory supercap as the buck output is set to 3.1v and it will only cost me $1-2 per car.

Would .47f be good enough or should I go to 1.5f? The bigger ones are twice as much but still pretty cheap. Or does this low farad level even matter? ie. “You need to do dual, expensive, 10f supercaps to make the bulbs stay on for more than a second.”

My concern with the larger ones is with the next question. Would a string of cars with double capacitors cause a problem due to inrush current?

#25

Derailed said:

I’m a “Roundy Rounder.” I like to run my trains on auto for hours while I sit by the fire pit, drinking and smoking

Me too

#26

I probably would enjoy operations. I just never had an opportunity.

#27

Derailed said:

I probably would enjoy operations. I just never had an opportunity.

I have numerous times but it doesn’t interest me. However I do enjoy taking pictures of the trains operating! Just a different aspect of the hobby I suppose.

#28

https://www.amazon.com/Cylindrical-Ultra-Capacitor-Supercap-10x26mm/dp/B07Q2HMJY9

6 of the 10 F 2.7 volt super caps for 4.99 plus shipping.

I have bought these in quantities for even less $$ and free shipping by looking around Amazon and E-bay.

Zimo decoders actually have a builtin charger for these caps which limits the current for charging in order not to trip the power source current.

#29

So, I would need two of these wired in series to get over the 3.2v output for the LEDs. I would have to wire them in after the buck board but before the leds? So the positive lead of the first Supercap would be soldered to the positive wire going to the leds. The Negative lead of the first Supercap would be soldered to the positive lead of the second Supercap and the negative lead of the second supercap would be soldered to the negative wire going to the LEDs?

How many farads does this give me if both Supercaps are 10f? 5?

#30

Yes, 2 identical capacitors in series will give 1/2 the Farads but double the voltage. Be sure to charge with a resister like 100 ohms (to limit charging current) but discharge via a diode for max available current on discharging.

#31

I believe you put the resistor between the positive leg of the supercap and the buck board, correct? Are100ohm half watts good enough?

Where do I put the diode? Is a 1n4004 good enough?

Update: I noticed Saturday night that over half my cars were really dim. Most of the leds had failed. I tested the voltage and they were all at a higher voltage than what I set them. Seems these Buck Boards are experiencing voltage drift (not sure what it is called). So I set the voltage to the minimum the bulbs need instead of the median voltage IOT give some more buffer in case it happens again.

#32

1n4004 is fine and it goes from the super cap to the leds.

#33

Finally got this wired in. I used a 5.5v 1.5farad coin shaped super capacitor. I get over 2 minutes of light from the 4 leds in my caboose. Though, they are pretty dim after 30 seconds.