# Help w/ USAT NE Caboose.



## bicyclexc (Mar 31, 2010)

I everyone. Today I decided that I would disassemble my WM center cupola caboose in order to try and re-wire it for battery power ONLY. I searched for some similar threads but couldn't find any help.

I removed the pickup brushes from the trucks, and the smoke unit/chip from inside along with the smoke unit switch. When I installed the 9v battery into the compartment I was *hoping* that the remaining inside lights, AND the marker lights would light up.

When I threw the switch for the lights (both directions), only the marker lights seem to be connected to the battery. Has anyone experience with making the 3 lights inside the cab also battery operated? Crossing my fingers.

Tom


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## Greg Elmassian (Jan 3, 2008)

A little too much load for your 9v battery. 

Put in a bigger battery, change to leds or both. 

Yes you will have to rewire, I assume you are NOT track power? 

Greg


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## bicyclexc (Mar 31, 2010)

Correct Greg. No more track power. There is one more circuit board inside the caboose that most of the wires hook up too, but IDK how its designed. Guess I'll cut it all out and rewire with just the battery. Any clue as to the voltage for the light bulbs?


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## Greg Elmassian (Jan 3, 2008)

Usually 5 volts, but that's a new caboose and have not tested it yet... so hook it to track power and measure the voltage. 

What size and voltage battery are you going to use? 

Greg


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## Dan Pierce (Jan 2, 2008)

Definitely change all lights to leds and wire similiar ones in series for a 9 volt battery to reduce current drain on the battery. 3 in series with a resistor rated at 60 ohms (56and 68 ohm are s standard values with 10 percent tolerance) for approx. 10ma at 9.6 volts. For a single 3 volt rated led, 560 or 680 ohm. 62 and 620 are available in 5 per cent tolerances. 


I would use the lower value as the battery output will diminish with use.


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## Greg Elmassian (Jan 3, 2008)

3 white LEDs in series requires approximately 10.8 volts... you won't get 10.8 volts from a 9 volt battery, at least not on this planet. 

Some leds will take less voltage, and a 9 volt fresh might light some of these, but a bad design. 

put 2 leds in series and you can use several sets of 2 in series. Use an LED calculator. 

(remember I asked the battery voltage, it was for a reason, a small 12v rechargeable might be a better idea) 

Greg


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## bicyclexc (Mar 31, 2010)

It would make sense for the bulbs inside the cab to be 5v since the battery seems to operate only the marker lights, 10v, and the track pickups operated the interior lights, 15v. 

Although I would like to use a larger battery, and there may be space now inside after removing all the other things, a basic 9v just seems too simple to turn away from (and cheep too). 

The lights won't be used very much.


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## Greg Elmassian (Jan 3, 2008)

Simple yes, but not a lot of capacity. See if setting the LED current to 10 ma instead of the standard 20 will be bright enough. That will help increase your battery life to acceptable. 

I believe you are looking at 5 lights total (I guess it does not have a blinking FRED)

Most likely the reason the interior lights were not hooked to the battery is that the load would be excessive, if they are incandescent, they could be up to 100 ma each!

Do you know if the marker lights are LEDs or not?

By the way, the price per "watt hour" for 9 volt batteries are anything but cheap, but I know you want to keep the same "battery box"

Greg


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## bicyclexc (Mar 31, 2010)

All bulbs are presently incandescents. With all of them LED's it should be feasible with a 9v. I was looking on radioshack.com and found 

http://www.radioshack.com/product/i...ce=CAT&znt_medium=RSCOM&znt_content=CT2032233 

Perhaps. The viewing angle is 12 degrees which is high, but it is 'amber' so maybe it will look incandescent. Any good LED suppliers out there with yellow LEDs and a higher viewing angle? 

Tom


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## Greg Elmassian (Jan 3, 2008)

Well, I'm trying to help but not sure I am communicating. 

High brightness is not really what you want... you really want a high dispersion high efficiency led.. 

You have picked a low dispersion (notice the 12 degree angle of output) low efficiency led. 

Get something that runs lower milliamps and with 120 degree angle of dispersion. 

This one has a 120 degree dispersion http://www.radioshack.com/product/i...ce=CAT&znt_medium=RSCOM&znt_content=CT2032233 

The point is that incandescent bulbs usually have a nice dispersion pattern, but leds tend to be a beam. You cannot illuminate the inside of something with sharp pencil beams. 

Regards, Greg


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## bicyclexc (Mar 31, 2010)

Following up here as I just completed re-wiring my caboose. For the record:

I removed the track pickups, both circuit boards, smoke generator switch and smoke generator. I cut all the plugs away and hard wired everything back together using the original lights switch with original wires, one throw lights the markers, the other lights the markers AND interior.










IDK what the interior lights were but I know the markers are 9v, 25mA incandescents. They are wired in parallel to the battery and I left them as such.The lights are very small diameter bulbs that fit inside small holes in the back of the marker, smaller than a 'normal' sized LED. To replace these would require a mini-LED, perhaps 3mm in diameter with an almost 180 degree field of vision, I have yet to see one like this.

The interior I replaced with this:
http://www.radioshack.com/product/index.jsp?productId=3060973&numProdsPerPage=60

These LED's are rated at 3.3V, 20mA. There are 4 pins but only 2 are needed. I found they fit nicely on the ceiling of the cab. They are wired in series to make 9v.










On paper the circuit draws 70mA of power. From a 9v alkaline that gives me about 7 hours. This works for me. That would probably be 3-4 running sessions, if all the lights are on. My meter measured less than 70mA though for whatever reason. If the lights in the markers could be changed to LED's this could be significantly improved.

Hope this helps someone else in the future!

Tom


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## Greg Elmassian (Jan 3, 2008)

I think you will find as the battery voltage drops, the 3 in series may go out, since they "want" 9.9 volts and you are only starting off with 9.0 ... 

So I don't think you will get 7 hours with them on, but please let us know how it goes. 

I see you took my advice and did get "high dispersion angle" LEDs... any pictures of the unit assembled? 

Regards, Greg


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## bicyclexc (Mar 31, 2010)

I agree, the 3 might go out eventually, could be helpful to judge the battery life. If it turns out the 9v just sucks massively I might consider doing 6 AA's somehow.

If anybody finds any tiny LEDs for the markers, don't hesitate. 

Ask and ye shall receive.


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## Greg Elmassian (Jan 3, 2008)

I use small surface mount leds, in different colors. 

Greg


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## SteveC (Jan 2, 2008)

Posted By bicyclexc on 14 Jun 2013 03:30 PM 
{snip...}[/i] If anybody finds any tiny LEDs for the markers, don't hesitate. {snip...}[/i]
Ngineering - Lighting Products[/b]


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