Atlas/Dapol Track Cleaning Car with Railpro?

[CPRail]

I picked up a BNIB Atlas/Dapol Track Cleaning Car for a song at our local train show this weekend. In reading the instructions it says it works on a maximum of 9 volts. It does have an eight pin plug for a decoder.

Has anyone set one of these units up for RailPro? Do I need to put in a LM to keep it "safe" or can I just use it on the RailPro track power? Seems a waste of a LM just to turn it on and off, but I suppose I could go nuts and install lights (beacons, headlights, etc.)

Thoughts?

[G8B4Life]

9v would seem a bit low. On DC it's obviously sharing whatever the track power is with the locomotive pulling it and most DC power packs deliver at least 12v, if not a bit more. RP's track voltage is 14 point something (I forget exactly these days) which is probably a enough to shorten the life of the motor more than you'd accept if it is a 9v motor but without seeing the circuitry inside it's a bit hard to tell.

All up, if you wanted to be sure you could simply splice in a couple of bridge rectifiers inline with the motor to lower the voltage to the motor (easier but not as elegant as a proper voltage regulator).

If you put an LM in, you could make an accessory project for it, load some custom rail grinding sounds etc into it, slap some Loram decals on the side and have a freelance rail grinder.

- Tim

[CPRail]

Hey Tim,

IIRC, the instructions did mention something about sharing the load with the loco. I'll have to re-read them. I'll also see about cracking it open and see the wiring. Gotta do it anyways to access the 8 pin plug.

Stay tuned.

[CPRail]

While on my lunch break, I found this page from TCS on the car:

https://drupal.tcsdcc.com/installation/ho-scale/1163

[gregeusa]

Interesting, it's stated that running over 9v will melt the solder on the pickup springs in the truck.

The implication is the current will go up enough the melt the solder, so, right off the bat, not a great design.

I'd put a diode chain in series with the motor lead to reduce the voltage the motor sees... that should keep the current levels below the "melt solder" levels.

(can you say poor design by Atlas?)

Greg

[CPRail]

I saw that too. One has to wonder for a 9V max system, just how much current is running through there that it can melt rosin core solder which has a general melting point of ~ 360° F (182° C)??

[gregeusa]

no, if run OVER 9v the solder may melt... assume 12v (typical HO DC voltage) now you are running the motor 50% in excess of design voltage, remember motors are usually nonlinear at the extremes...

I would guess the copper "springs" (look at the pictures) to the axles have too much resistance and create heat....

[CPRail]

Ahh, that would explain why I read a reference to hard-wiring the pickups.

I gotta crack this thing apart in the next day or so and see what I'm working with here!

[gregeusa]

yeah, run it at 9 volts and check the current draw, then run it briefly at 12v and note the current.