Let's say I forgo using a bridge rectifier in lighting a caboose. I'm using Intermountain semi insulated wheels and have them properly oriented (one truck set with noninsulated wheels leftside and the other truck set rightside.
Now I use a wire wrapped around one live axle on each truck and run it with a resistor in line with the positive LED lead and the other wire on the other truck to the negative lead. I then install a second LED wired to the remaining 2 live axles with the resistor on the negative wire and basically reverse the connection. Will the first LED light in one direction of travel and the second one light in the opposite direction of travel?
I guess this shows my limited electrical knowledge but it's worth asking.
Cedarwoodron
well, yes ....
but it doesn't matter if you put the resistor on the positive or negative lead of the led
it would be easier to run a bridge diode in front of just one led though
cedarwoodronWill the first LED light in one direction of travel and the second one light in the opposite direction of travel?
No. They will both be lit as long as track power is applied in DCC. Yes, if you are talking DC.
I use LEDs "hot-wired" to DCC track pickups to illuminate locomotive number boards and passenger car and caboose lighting. They are lit all the time. I don't use a rectifier.
IF I were to place the same cars or locomotives on a DC powered rails then, yes, the LEDs would only illuminate when the anode side was seeing the positive rail.
Good Luck, Ed
This is correct on DC. The issue is that you will shorten the life of your LED. The reverse voltage on the LED will eventually burn it out albiet it will take a while. By putting in a regular diode in parallel but opposite of the LED you can mitigate this issue. or if you use the same set of Leads from the truck and wire the LED's cathode to anode in parallel it will do the same thing.
DCC both LED's will light up since it a square wave signal that goes both positive and negative.
Colorado Front Range Railroad: http://www.coloradofrontrangerr.com/
LED wiring aside - when I do my caboose installs, I put opposite insulated wheels in the same truck (a left and a right insulated on the same truck). This way there is less chance of power loss on a dead frog for example. The distance between two axles on the same truck could easily lose power on the length of a dead frog. With the distance between two axles on opposite trucks being much greater, when one axle is on a dead frog, the other is well clear and has a good chance of still picking up power.
Mark.
¡ uʍop ǝpısdn sı ǝɹnʇɐuƃıs ʎɯ 'dlǝɥ
Mark R.This way there is less chance of power loss on a dead frog for example.
If you can get away with modern roller-bearing trucks, Athearn has caboose trucks with all eight wheels picking up. I have made requests to them to produce an older style truck with plain bearings and electrical pickup but so far, no dice.
These are nice since they utilize the needle-point for contact with a bronze strip so there is very little rolling friction.
http://www.athearn.com/Products/Default.aspx?ProdID=ATHG4593
They have five varieties, some with wire already attached, some not.
http://www.athearn.com/Products/Default.aspx?ProdID=ATHG61383
Some types have "Rotating end caps". These are fun to look at but don't roll quite as freely. There is that possibility that the bearing cap can pop off.
gmpullman Mark R. This way there is less chance of power loss on a dead frog for example. If you can get away with modern roller-bearing trucks, Athearn has caboose trucks with all eight wheels picking up. I have made requests to them to produce an older style truck with plain bearings and electrical pickup but so far, no dice. These are nice since they utilize the needle-point for contact with a bronze strip so there is very little rolling friction. http://www.athearn.com/Products/Default.aspx?ProdID=ATHG4593 They have five varieties, some with wire already attached, some not. http://www.athearn.com/Products/Default.aspx?ProdID=ATHG61383 Good Luck, Ed
Mark R. This way there is less chance of power loss on a dead frog for example.
These look good, but the delivery says late Dec 2019.
Might want them before then.
Don
Carolina NorthernMight want them before then.
Google?
https://www.ebay.com/itm/Athearn-Genesis-G4593-Caboose-Truck-with-Late-Generator-HO-1-Pair/132609374156?epid=3018939359&hash=item1ee02277cc:g:bAAAAOSw~2VcAo~Y:rk:1:pf:1&frcectupt=true
https://www.horizonhobby.com/ho-caboose-truck-early-generator-%282%29-athg4592
https://www.modeltrainstuff.com/athearn-genesis-ho-g4593-caboose-truck-with-late-generator-1-pair/
https://www.modeltrainstuff.com/athearn-genesis-ho-g4592-caboose-truck-with-early-generator-1-pair/
There are alternatives.
Ed,
Those Athearn caboose trucks are neat. The fleet of cabeese that I built for my Algoma Eastern RR use the power pick ups from Streamlined Backshop. The power pick ups work fine but they have a lot of rolling resistance. They have never caused derailments so maybe I don't need to worry about them.
http://sbs4dcc.com/hoscalewheelwipers.html
I'm not sure if I want to buy 8 sets of new trucks though. That would cost me about $210.00 Cdn. to solve a problem that may not exist.
Thanks for pointing them out.
Dave
I'm just a dude with a bad back having a lot of fun with model trains, and finally building a layout!
Having a little drag on the tail end of the train probably isn't a bad thing - probably keeps the cars from bouncing back and forth because of the slack action in the couplers.
Can;t be anywhere near as bad as the first run P2K Northeast cabooses. Excpet with those, it's not the power pickups - it's the brake shoe detail, which out of the box rub on the wheels. Someone modeled the darn things with the hand brake set! I just remove the brake shoe detail parts on mine.
--Randy
Modeling the Reading Railroad in the 1950's
Visit my web site at www.readingeastpenn.com for construction updates, DCC Info, and more.
hon30critterI'm not sure if I want to buy 8 sets of new trucks though.
Only pointing out an option, Dave. Essentially I was responding to Mark R. who offered the good suggestion of staggering pickup wheels on one truck.
I have used these Athearn caboose trucks with the generator detail filed off to supply power to a Soundtraxx Soundcar equipped mechanical reefer. The engine starts and stops randomly and there's also squeal and brake shoe squeak, too.
Again, it's only one choice among many. I found them for about $15/pair. For me that is a reasonable cost rather than my time involved with fussing with bronze wipers and such.
Cheers, Ed
That's great if you aren;t following a specific prototype or else they are the correct ones for your prototype, but those AThearn trucks are wrong for what I model, so it's DIY for me if I want to put lighting in my cabeese. On one hand, I think it would be neat if I did ALL of them, on the other hand - I have some that are more detailed models than others and I was thinkign of just adding lighting on the nicer ones. Flickering oil lamps inside, and battery powered markers - in my era on my road that's about as far as they got with electrification.
Now if someone made Taylor caboose trucks with built in power pickups..
gmpullmanOnly pointing out an option, Dave.
Yes Ed, sorry if I sounded negative. I was just thinking about the reduced thickness of my wallet if I went that route.