Atlas/Tomix Track Cleaning Car - What is the "CL" switch position?

[mmagliaro]

I just got one of these a bit on-the-cheap.  After adjusting the truck pickups, oiling the motor bearings, and
running it at a variety of speeds to rid the armature of carbon in its slots, it runs really nice and the vacuum
pulls up an alarming amount of junk and fuzz from the track, which is what I hoped.

The power switch has 3 positions:  Off, "CL" and On.
The instructions just say not to run it at high speed in the CL position.
This is all assuming the car is just running on DC off the rails (which it is).

So what is "CL"?  ("Current Limited"?)

I get the feeling from the one-line warning in the instructions that this car has a less-than-12v motor in it,
and in "CL", the motor runs straight to the rails, while in "ON" it has, perhaps, a dropping resistor in series with it?
Although, the motor speed does not change when I flip it from "ON" to "CL".

[peteski]

I have one of those (well, the one sold by Atlas) and I took it apart when I first got it to see how to install the DCC in it.  But I don't recall what that switch does...

[brill27mcb]

CL is a Tomix designation for their Constant Lighting feature. If you don't use a Tomix power pack with the CL feature, you have no need for it. Their power packs use pulse width modulation (PWM) to vary the track voltage (a high-frequency 12-volt activation of variable duration, so for example if it is set to be on three-quarters of the time you get an average of 9V DC. The CL feature is simply a dial  to adjust the minimum voltage duration setting to a width that turns the LED lights on, but does not turn the motor over, so the train can be stopped and the lights remain on.

If you do go to DCC, you will need a decoder for the vacuum and rotor motors so they don't get the higher-than-12-volt DCC track voltage, but you then get the advantage that you can also set the motor speeds separate from the train speed. I do not use DCC, but there are discussions online about how to do this. Hope this helps!

Rich K.

[mmagliaro]

That was very helpful, thank you!

[carlso]

Hi Max,

Not to sure that you are putting decoder in the beast but when I put a TCS into mine, all the factory switch parts were removed and the motor was just wired to the decoder. I also installed two yellow beacons on the top to add some pizzazz while cleaning the track.

I too was amazed at how much junk the vacuum picked up off of the tracks. Amazing how many trip pins and small screws it can find.

have a good day.

Carl

[mmagliaro]

Thanks Carl, but no, no decoders for me.  I don't do DCC.
I just push or pull it behind a geared-down switcher, and the DC track voltage is plenty high enough
to rev the vacuum and make it work well.

[Scottl]

Resurrecting this thread for some more input, if possible. 

I am interested in one of these Tomix cars and would like to run it on a DCC layout, but not install a decoder or have any lighting.  My thought is to to take track power and run it through a bridge rectifier and 12V regulator to give me DC for the vacuum and rotary motors.  Does this seem viable? 

Does anyone know what kind of current draw the vacuum takes?  My DCC system provides 2 A (NCE Power Cab)- I assume that should be enough but I don't want to overload it.

[C855B]

Reasonable idea. I haven't looked at the current draw on mine so can't offer a direct answer about load. If somebody doesn't jump in beforehand, when I get over to the layout today I will measure it. My main issue with a regulator is that it might get warm if you're talking about your run-of-the-mill 7812 or even a modern switching equivalent. Pete will have to jump in on this.

For a few moments I was thinking it already had a rectifier in it since the motor would run backwards on reversing the DC track power, and the vacuum would become a blower. However, the fan is a straight-blade centrifugal type, so airflow will be right in either direction. Probably not the most efficient vacuum fan since scroll blades are better in this application, but it is an easy solution to motor reversing.

[Scottl]

Interesting.  I could always put the regulator on the outside to increase heat dissipation. I don't care what it looks like, I just want it to function reliably.  I can get one for about $45 CDN  and a decoder would add 50-100% more cost.

[eric220]

I’ve managed to run these things on address 00 with success. Since you’re running them constantly, you don’t have the issue of the motor oscillating at low speeds.

[Scottl]

I think I am missing something here.  How does running it on address 00 come into it?  I assume you are equipping the cleaning car with a DCC decoder?

[C855B]

Address "00" changes the DCC AC waveform so it is biased to have enough of a DC component to run non-decoder equipped locos. It tends to make motors buzz (and heat-up) at low throttle settings, but it might be good enough to run the vacuum motor at 80-100% throttle. The question since I don't know NCE is whether NCE supports 00; I've only used it (and very limited at that) on Digitrax.

[MK]

DCC address 00 is used to run DC locos (without a decoder) on a DCC layout.  At least that's the Digitrax way.  What Eric is suggesting is that tread the cleaning car like the DC loco with no decoder.

If you run it near top speed then you won't have the issue of a hot motor.  People have said that if you use a DC loco, again without decoder, on a DCC layout, it will make the motor hum - even it sitting still.  The faster you run the loco the less of this humming and oscillation.  But of course your train will be at rocket speed. 

[MK]

Damn, no Modify feature still.  Mike snuck in there and I got a bunch of typos in my post! 

[C855B]

Ha!   

It just occurred to me that I should be able to test the 00 thing, too. It'll be a couple of hours before I get over to the layout, so you might want to sit and keep refreshing the page until I get back.