APU Beacon

[johnnetzlof]

G&W has begun installing Auxilary Power Units in the locomtoives running in the colder regions. This APU basically is a small motor that keeps the oil and coolant warm and flowing as well as the batteries charged while the locomotive is in a shutdown state. G&W's APUs also shut the unti down after a halfhour of no activity. This APUs have an external beacon, about the size of my fist on the hood which will blink when there's a problem with the APU.

You can see 3301's Blinking APU beacon in these pictures.
rrpicturearchives.net/showPicture.aspx?id=1468855
rrpicturearchives.net/showPicture.aspx?id=1468864
3301's APU has a bad starter circuit, meaning it won't kick on, also meaning the beacon is in a constant state of flashing (til mechnics can fix it.)

Does anyone know of a beacon small enough I can replicate this? it sits on a little shelf on the hood side, and like I said, the beacon is around the size of my fist.

I'm thinking I may throw a small bulb in a couple of units to add some opperating flavor, the units with the blinking strobe would be restricted from being th elead unit or what not.

[DRLOCO]

Just so you know--the thing looks remarkably similar to the old western-cullen beacon that you used to see on BN F's. It's that fast rotating beacon thingy whizzing around a stationary bulb.
It's teardrop shaped, not round, however.
THe K9APU system (owned by a guy who worked at CSX, and CSX is the largest purchaser of these units, go figure.) places a small diesel generator back underneath the radiator fans in the carbody. When working properly, it keeps the fluids warm, and batteries charged. It also has an option to put heat in the cab. THis unit will only use about a quart of fuel oil per hour, as opposed to a GP38 Prime mover, which would consume 1/4 of a Barrel of fuel in the same 1 hour period.
The only time that light on the hood you are looking at is lit is when the APU is active, but has had some form of malfunction. IF the APU is off, it won't flash. IF the APU is working as intended, it won't flash.
Now, you *could* have a flashing LED or bulb inside the hood, and then just use a small filliment of fiber-optic cable to get from inside the hood up to that bracket. In reality, there really is a small electrical conduit running from the hood out to the bottom of the bracket where the light is bolted down.
If you *really* want to get realistic, you could also model the really annoying <beepbeepbeepbeep> that the thing makes in conjunction with the flashing APU light.
hope that helps.