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.
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.
Here's the completed harness. Note the decoder harness as well.
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.
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.
Close up of the completed unit...
And the real fun.
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.
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.
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.
Here's the completed harness. Note the decoder harness as well.
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.
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.
Close up of the completed unit...
And the real fun.
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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