Spectrum 2-8-0 Front Light Issue

[russ daley]

I reviewed posted threads and explored the internet but remain uncertain how to proceed.

I revived a 2-8-0 from my junk pile with a parts purchase from Bachmann. I will say Bachmann did a great job with my order. I had removed the circuit board a long time ago so I retraced the hard wiring and installed a TCS T1A Decoder. All programming went well except I can't get the front light to light.

The Model Spectrum is 11410. Bought new guessing 2005 or 2006 era. I'm not sure if existing light is a bulb or a LED. The parts list looks like a bulb. I did wire the light to an aux power source and slowly increased current until the light lit green and then backed off. So the light appears to be ok...

As to wiring...and to be on the safe side I installed a 1K ohm resister between one of the light wire leads to the blue wire lead of the decoder and the other light wire lead to the white wire of the decoder. I then switched around the light lead wires...same results..still no light.

Questions:

1) If it's a bulb do I need a resistor? Could having the resistor installed be my problem?
2) Is there a CV Function that permits the light from lighting. I use a Lenz LH100 Keypad. In all my years messing around with DCC and decoders...I never had to be concerned with any associated function.   
3) In checking the resistor, I had conductivity across the leads.

Any help of course is appreciated.     
Russ Daley

[russ daley]

Progress...

I wired a 16 Volt Incandescent Lamp into the circuit with the resistor and the lamp did not light. I bypassed the resistor and the lamp lit. This tells me that the decoder and CV Values are correct. All I need now is a warm comfort reply telling me that there is most likely an Incandescent Lamp installed...remove the resistor...study Ohms Law, button it up and move on...   

[trainman203]

I'm no electrician, only working with common sense. If that bulb came with the locomotive, it should be properly rated for whatever current powers the locomotive. It appears to be a DC locomotive so my best guess is that that was probably somewhere between 12 and 15 V that ran that engine.  That's what HO scale DC Trains have always run on. (except in the Jurassic, I think 6 V was used.) Ergo, no resistor needed, at least I think so. 

I'd take the resistor off and just try the engine. All you can do is burn it out, and then replace it with an LED, which is much a better looking and brighter light, but would require a properly rated resistor.

Jeffrey Ward, you're the electrician, please elaborate and elucidate.

PS there is no doubt that that is an incandescent bulb in that locomotive.

[russ daley]

Thank you for reply...

The Locomotive was a "New" DCC Ready Model Spectrum 11410. Over the years I removed the circuit board and ran it until somewhere along time the white metal chassis crumbled apart. I recently purchased a replacement chassis from Parts. I'm far from being an electrician too but I do agree it's worth the chance to remove the resistor and see what happens...But then again, I'm not a good mechanic either and I dread tearing these locomotives apart for fear of not getting them back together. I've managed a degree of success and learned a great deal so far with any teardown I've challenged but just trying to eliminate another chore....

Thanks again...             

[jonathan]

Dunno if this will help:

The original bulbs in the Consolidations were incandescent. I replaced them with LEDs and added a 1K ohm resistor, paying attention to polarity. Wire colors are not reliable with these locos.

Regards,

Jonathan

[russ daley]

I guess this Chapter of Learning is almost closed. I have another 2-8-0 which was also torn apart (same issue white metal chassis failure) so I connected full voltage to the light and it didn't blow. It remained connected for 5 minutes. So for now I'm going to be content with the incandescent lamp. And thank you Jonathan for confirming a few questions I had regarding the wiring of a LED. Thank you trainman 203 also...

OK...next project fix...double crossover in a reverse loop....any takers?

Russ, 

[trainman203]

Track plan please