tstage Rich, The only ones that will melt your shell (besides incandescents) are FEDs: Flame Emitting Diodes. With LEDs you'll be just fine. Tom
Rich,
The only ones that will melt your shell (besides incandescents) are FEDs: Flame Emitting Diodes. With LEDs you'll be just fine.
Tom
Ok, I stand corrected. lol
Rich
If you ever fall over in public, pick yourself up and say “sorry it’s been a while since I inhabited a body.” And just walk away.
https://tstage9.wixsite.com/nyc-modeling
Time...It marches on...without ever turning around to see if anyone is even keeping in step.
Most locos with 12 volt bulbs are never run at 12 volts with DC power packs unless you run your loco at max speed. With decoders, the bulb always gets 12 volts and some find out the bulb now melts the shell and wonder why. That is another example of assuming with DCC.
Some are not low current. All light bulbs are not created equal.
I have seen some partially melted headlight housings because some assumed not enough heat to damage anything. Some DCC systems run about 14 volts also.
Many never do any kind of research before converting locos.
Some like light bulbs as the bulbs can have better lighting characteristics than LED's.
A low mA bulb rated at 16V won't melt your plastic either when powered at 12V.
Richard
With a 1k resistor at 12 volts, the current will be about 0.009 ma. That is 0.08 watts and a 1/4 wtt resistor is what most use.
LED link below.
https://sites.google.com/site/markgurries/home/part-sources/led-s/resistors-for-leds-bulbs
OK, thanks guys.
I "knew" that, but I still needed to hear it once again and be reassured. I cannot handle any more bad news with my beloved NKP 2-8-4. I have already done enough damage.
Alton Junction
If your LED generates enough heat to melt plastic, something is REALLY wrong. Even if you were to do something really dumb like forge thte reistor, during that bried moment when the LED converts itself into a DED there will be nowhere near enough head to melt plastic.
The only LEDs that generate the kind of heat you get from a 12V incandecent bulb are those really big ones used as car headlights and high brightness flashlights (not the single LED kind, the ones that work as 100,000 candlepower spotlights). They generate a few watts of heat (still way less than the equivalent incandescent) and usually have heat sinks attached to protect the diode junction itself. They'd never fit in an HO loco so - no chance of ever melting the shell.
--Randy
Modeling the Reading Railroad in the 1950's
Visit my web site at www.readingeastpenn.com for construction updates, DCC Info, and more.
Be of good cheer. LEDs generate almost no heat. Your engine will be fine.
Be careful where you put the resistor, though. If you're using a decoder that runs the lights on 12 volts, the resistor will generate more heat than the LED, so you don't want to put the resistor directly against the shell.
It takes an iron man to play with a toy iron horse.
A few weeks ago, I installed a 12 volt incandescent bulb into a plastic head light housing on one of my steamers. The heat from the bulb began to melt the housing. So, I replaced the incandescent bulb with an LED.
Now, I need reassurance that the LED will not generate sufficient heat to melt the housing like the incandescent bulb did.
The LED is a Miniatronics Yeloglo White Ultra Bright 3mm 2-4 VDC (#12-310-05).
Am I going to be OK with setup? It looks great, but I am afraid to leave it on until I hear that it will run cool, not hot.