Advanced Lighting for a P2K Geep.

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grande man

Bonafied Grande Nut
Hi all. The past few days have been quite a learning experience. We've been adding lighting effects to our GP 30's. I'm posting this because I wish I'd had more info before starting. It would have saved much time/aggravation. I'll mention a few of the school-of-hard-knocks mistakes made (we did 2 units) but basically want to show a good route to take for adding the lights. Even then, you'll need a heavy dose of patience to complete the job.

I'll start by saying that a Digitrax DH163LO decoder was used. Miniatronics 1.7mm 12 volt bulbs were used for the front, lower headlight and 1.2mm 1.5 volt bulbs were used with 560 ohm resistors for the class lights. These lamps basically fit the existing holes in the P2K shell. [red]First and foremost, check your bulbs before wiring them to a decoder![/red] More on that freak incident later.

Be sure to grind the frame enough to provide adequate clearance for the new lights. This will save you many broken bulbs and much heartache when it comes time to put the shell back on. The frame is aluminum and will clog sanding bits and carbide cutters so I'd recommend a new grinding burr. Start by taping and wraping any area that shavings could enter. Here's a pic. It's not pretty but the idea is clearance, not looks. Note the channel for the wiring lead.

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As for wiring, a Miniatronics 4 pin harness/connector is the way to go. Since there are four lights, each on a separate decoder function, a separate common ground was added. It was not soldered to the decoder's common pad, rather it is hooked into the standard blue wire common solderless connector that plugs into the decoder so as to provide a quick disconnect feature to facilitate later shell removal. The 4 pin connector needs to be located back by the decoder. On the first engine I located it forward in the cab area but it's somewhat visible thru the cab windows, not good. Use only the F1 and F2 decoder ports for the class lights and don't forget the 560 ohm resistors. Set the harness up using this link, http://www.digitrax.com/ftp/fxsetup.pdf

This pic shows the completed forward half of the harness before a final piece of heat shrink was added to "keep it all together". Note the heat shrink on the bulbs to keep them from pushing forward.
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Here's the completed harness. Note the decoder harness as well.
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The forward harness installed in the shell. The blue tacky adhesive was bought at Lowe's. Use it sparingly to prevent a mess if you need to remove the shell.
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The shell almost ready for installation. The aft harness lead will be routed under the decoder and then back around the right side. The connector will be over the forward half of the decoder when installed. Note the white common lead and where it's hooked up.
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Close up of the completed unit...
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And the real fun.
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As noted in the second paragraph, please check your bulbs before hooking them to a decoder. If you noticed in the last pic that one lower headlight is a little brighter than the other it's because a shorted (that's right, shorted, not open) bulb fried an FX output on the decoder! I've never seen a bulb fail this way before but it was verified with a meter. I had to go back in (thank God for the quick plugs), remove the offending bulb (I'm out of them and the decoder output is kaput) and add the factory clear headlight plug to the upper light position. Some heatshrink was removed from the lower lamp to let it illuminate the upper unit. Surprisingly, while it shows in the photo, a difference in brightness between the two isn't very evident in person.
 
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jbaakko

Diesel Detail Freak
WOHO! Thanks for the advice, my BNSF GP30 is going to have the same treatment, sort of. The headlights are in the nose too, but the ditchlights are none operational, becuase I didn't feel like wraping the wiring down under the frame, who cares, she prolly won't lead to much, Cajon is a region of widecabs!
 

grande man

Bonafied Grande Nut
One more problem I just noticed, the shell on the first unit is beginning to melt aound the headlights!!! It was caught early enough that a Details West light will fix it but a quick call to a friend who's done all this before confirmed that he mounts the lights in a piece of brass tubing to act as a heat sink for just this reason. I'll have to get some this week and remount all the lights. :eek:
 

grande man

Bonafied Grande Nut
Well, I just got the unit with the melted plastic back up. A Details West light and brass heat sink tubes took care of things. In fact, it may look a little better than original. Now that I've learned some of the snags in modifying loco lighting, they should be much easier to do in the future. We really like the effects advanced lighting provides to the RR's realism.
 
Grande man - Great info. I think I might just give it a try on one of my Geeps. However I have a question? Have you ever considered using LED's. No heat! Just wondering if I am missing something that would prevent LED use. Thanks for the info.
Terry
 

grande man

Bonafied Grande Nut
scubaterry said:
Grande man - Great info. I think I might just give it a try on one of my Geeps. However I have a question? Have you ever considered using LED's. No heat! Just wondering if I am missing something that would prevent LED use. Thanks for the info.
Terry
Well Terry, originally, we wanted flashing ditch lights but later learned these are classification lights :eek: . Anyway, Digitrax recommended incandescent lamps instead of LEDs. Can you get an LED that small? The class lights are 1.2mm (.047") and the headlights are 1.7mm (.067"). I do know that the 1.5 volt lamps run cooler, the resistors now, that's a different story.
 
Grande man - Those darned MM mess me up everytime. You are probably right it would be difficult to find an LED that small. I figured you must have a good reason not to use LED's. Thanks for responding.
Terry
 

grande man

Bonafied Grande Nut
Guys, one thing I should also tell you is that some DCC users go with 16v bulbs. Our track voltage is right at 12v but some power supplies run higher. Be sure to keep that in mind if it affects your installation.
 




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