Trains.com

Subscriber & Member Login

Login, or register today to interact in our online community, comment on articles, receive our newsletter, manage your account online and more!

Locomotives and light bulbs Question

1026 views
3 replies
1 rating 2 rating 3 rating 4 rating 5 rating
  • Member since
    December 2007
  • From: Gateway City
  • 1,593 posts
Locomotives and light bulbs Question
Posted by yankee flyer on Saturday, October 31, 2009 5:08 PM

 HI all

I have a loco that I pefer not to use an LED in because the DSD LC does'nt like LEDS. It calls for  12V bulbs and I
have 12Vs at 50 MAs and 5.5mms. Can't swear for the millie amps.
Also have 1.5V 90 MAs? and 2.4 mms.
How do you tell how bright they will be? the little one take up less space but I would have to use a resister. I have room for the bigger ones and I don't need resister.
I'm not sure what size looks best in a loco for brightness.

Thanks 

Lee

  • Member since
    October 2006
  • From: Western, MA
  • 8,571 posts
Posted by richg1998 on Saturday, October 31, 2009 5:49 PM

 I do not use light bulbs but I would watch out for the heat from the bulbs. Some people have had melting where the bulb is if in a plastic shell. Usually they had a 12 volt bulb. Some put the bulb in a brass tubing and use that as a heat sink. Many use 1.5 volt lamps like Miniatronics that require about 30 ma. or so with a resistor and do not run hot from what I have heard.

With an LED, all you would require is a 1,000 ohm resistor. I have used those decoders and no problems when a resistor is used. Many people do that.

SoundTraxx sells a Tsunmai decoder that puts out 1.5 volts just for 1.5 volt lamps and no resistor needed.

All the decoders put out 12 volts DC or so depending on the voltage used to run the controller and 1k resistors are required for an LED.

Connect the lamp to 12 vdc and see how hot it gets when not in an enclosure.

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.

  • Member since
    July 2003
  • From: Sierra Vista, Arizona
  • 13,757 posts
Posted by cacole on Saturday, October 31, 2009 7:03 PM

 I've used LED lighting with many SoundTraxx DSD LC decoders with absolutely no problems -- just put a 1K Ohm resistor into one of the LEDs wires and they work just fine with any decoder.

  • Member since
    February 2002
  • From: Reading, PA
  • 30,002 posts
Posted by rrinker on Saturday, October 31, 2009 7:44 PM

 If you DO use bulbs, use 1.5 volt 10 or 15ma ones, they don't get hot. You'll need resistors if the function output is 12 volts, 680 ohm might be a bit low but 820 is probably too high.

                                       --Randy

 


Modeling the Reading Railroad in the 1950's

 

Visit my web site at www.readingeastpenn.com for construction updates, DCC Info, and more.

Subscriber & Member Login

Login, or register today to interact in our online community, comment on articles, receive our newsletter, manage your account online and more!

Search the Community

ADVERTISEMENT
ADVERTISEMENT
ADVERTISEMENT
Model Railroader Newsletter See all
Sign up for our FREE e-newsletter and get model railroad news in your inbox!