Biggest reason to use LEDs with DCC:
With DC, you don;t usually spend most of your time running at full throttle. Instead you are more like half to 3/4. So the bulbs see 6-9 volts. They last a long time, and don't get all that hot.
With DCC< there is full voltage on the track at all times, and the functions merely switch this on and off. So any bulbs are running at full voltage all the time (unles you turn the headlight off). Thus it runs hot, and runnign at full rated voltage or slightly above greatly shortens the life.
With LEDs, it's pretty much the opposite. If you set one up on a DC loco, and pick a resistor that keeps the current well within limits at 12 volts, it might be too big for slower speeds, so the light will go out. With DCC, since the voltage is a constant, it's easy to pick a proper resistor, and it always works.
--Randy
Modeling the Reading Railroad in the 1950's
Visit my web site at www.readingeastpenn.com for construction updates, DCC Info, and more.
If you decide to stick with incandescent bulbs, resist the temptation to use 12 volt bulbs and stick with 1.5 volt bulbs. The on board resistor on the decoder will prevent the bulb from burning out due to excess voltage.
I recently installed a 12 volt incandescent bulb as the headlight in one of my steamers, and the heat melted the number board. I am heart sick over that stupid stunt. The owners manual even recommended a 12 volt bulb.
12 volt incandescent bulbs are incompatible with tight fits in plastic housings.
If you can use an LED. That's what I did to replace the 12 volt incandescent bulb.
Rich
Alton Junction
They are connected through diodes on a small .50 inch board. So, I assume that they are 1.5V.
Thanks guys for all the great info. I will probably go with LED's. I like the idea of longevity and not having to replace bulbs periodically!
-Al
Then there's the 3V bulbs in P2K locos. With a AA battery, a 1.5V bulb would be bright, a 3V bulb would be dim, and a 12V bulb, no go.
ANother way to tell is to look at the original wiring. If the bulbs connect to the track pickups, or across the motor terminals, they are 12V bulbs. If they connect through a resistor, or across some diodes, they are 1.5 or 3 volt bulbs.
This decoder is set up for LED's with no need for resisters. Go this way. To check the bulbs, take the leads of one of the bulbs and hook them up to a AA battery. If the lights glow bright they're 1.5V if not than 12V. Hooking up a 1.5 volt bulb to 12V will burn it and could damage the decoder. LED'sare better in a lot of ways. Joe.
LED's are preferred but Digitrax decoders don't work well with them for some effects like ditch lights.
LEDs last forever, and they don;t even get warm. Good enough reasons forme to always switch out bulbs when I install decoders.
OK, not literally forewver - but longer than I will be alive, my kids will be alive, and probably my grandchildren (shoudl I ever have any). I hate tearing apart locos multiple times, so anything that reduces how often I may have to open it up is a plus.
I would definitely go with LEDs, Al. They're cooler and the beam is more direct than incandescent bulbs.
Tom
https://tstage9.wixsite.com/nyc-modeling
Time...It marches on...without ever turning around to see if anyone is even keeping in step.
I am new to DCC. I have installed a Digitrax DH156KO decoder into one of my Kato GP35 (older model without the more current light board). It runs great. However, I haven't addressed the head and rear lights yet. I am not sure what lamps are in there i.e. 12V or 1.5V lamps. There are resisters there, so I assume that they are 1.5V. I have heard that if you are not careful with lamp selection, they can get hot, and possibly damage your loco's plastic surfaces if they become too close. Also, what is there that I should know about LED's. I know what they are, but is there a reason to use LED's over using 1.5V lamps?
To install the DH165KO, the bracket holding the lamps can't be used due to no place to mount it, or is there a good way to install the lamps?
This is probably an issue you have covered before, but, I sure like some guidance in it!
Thanks.