Speed limiting in analogue for a junior user

OBBherr

OBBherr

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We are trying to arrange a smalll layout for a young friend where he can control the trains himself. However in the case of this particular little tyke I need to arrange a speed limiter as I know the dial will go up to 11 as soon as he gets his hands on it.

We'll be starting with a Playmobil engne and working up to a Stainz when he can be trusted (which could be several years). I know I can limit speed with digital but he won't be allowed near my Massoth setup until he's at least 35.

I have moderate electrical skills at the low voltage end of things (never touch anything mains) but I can solder and do the basics. Can any of you experts out there provide guidance on how to limit max speed with an analogue controller and locos?
 
P

playmofire

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One way is to fit an obstruction on the controller so the speed control cannot be turned past a certain point if you domn't want to dabble with electrics. Having said that, Playmobil locos are robust things; I've had one land on the floor at from a display table when a young "researcher" decided to see what happened if he operated a point lever.
 
Rhinochugger

Rhinochugger

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I was just thinking the same thing - a couple of small short self-tappers, one on the dial, the other on the box ;);)
 
Greg Elmassian

Greg Elmassian

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Or just a "dropper" made of diodes to reduce the top voltage, easier, no mechanical modifications.

look for the voltage dropper pictures and explanation on this page:

 
T

TonyMP52

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I was just thinking the same thing - a couple of small short self-tappers, one on the dial, the other on the box ;);)
I've seen this done on the controller of a DEMU on a preserved railway to stop the temptation of going to Notch 7.....
 
dunnyrail

dunnyrail

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Hm not sure that the gist of what can be done with DCC is being thought about. Top speed can be severely limited with CV 5, changing the value of that to 70 will certainly slow anything down to an acceptable level.
 
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phils2um

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Be aware that a Märklin mfx/dcc loco sound decoder maximum analog speed is not limited by CV5 if you decide to go the CV route. We found this investigating the Borsig sound issue earlier. CV177 controls the maximum analog DC speed in Märklin loco sound decoders. But, check your decoder's CV table to verify.
 
dunnyrail

dunnyrail

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Be aware that a Märklin mfx/dcc loco sound decoder maximum analog speed is not limited by CV5 if you decide to go the CV route. We found this investigating the Borsig sound issue earlier. CV177 controls the maximum analog DC speed in Märklin loco sound decoders. But, check your decoder's CV table to verify.
Timely reminder that not all Chips have the same CV’s for speed, but he did mention Stainz and PM so my assumption was that there may be anLGB or Massoth chip within.
 
a98087

a98087

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You can add a 12v 5watt bulb in series with the fed to the track

or just use a 12v oo/ho gauge controller, instead of the lgb 24v controller.

this idea will only work depending on what the amp rating is on the controller

Dan
 
PhilP

PhilP

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You can add a 12v 5watt bulb in series with the fed to the track

or just use a 12v oo/ho gauge controller, instead of the lgb 24v controller.

this idea will only work depending on what the amp rating is on the controller

Dan
If you do this, and small people are involved:
Please make sure the bulb is arranged so it is not able to be touched by anyone. - It will get hot enough to hurt. - It also needs to be arranged so as to be safely away from anything it might damage.

PhilP.
 
OBBherr

OBBherr

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Thanks for all the ideas and associated warnings. We are definitely talking analogue solutions here.

Q to The Shed - is the illustrated module off the shelf and if so from where?
 
dunnyrail

dunnyrail

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Thanks for all the ideas and associated warnings. We are definitely talking analogue solutions here.

Q to The Shed - is the illustrated module off the shelf and if so from where?
Sorry I missed the Analogue thing and wittered on about DCC. Perhaps a different solution may be to have a Battery Loco for just the kids. A Stainz with just 4 aa will run but very slowly, for a controlled solution a full battery setup with reciever and speed controller set to its lowest possible top speed will keep things in check even if the control knob is turned to full blast.

I know what you mean about kids wanting full speed, back when I had my x’s grandees round regularly I had a RC Car with conventional 7.2 battery pack. But somewhere I managed to get an 8.something pack that really made that car wizz much to the delight of the kids. I like the 8 was the oldest favourite saying.
 
The Shed

The Shed

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Thanks for all the ideas and associated warnings. We are definitely talking analogue solutions here.

Q to The Shed - is the illustrated module off the shelf and if so from where?


Seller umtmedia, only connection as a satisfied customer.

The item is available else where..........

Re, the Playmobil engine, depending on the model, seem to recall this may require a lower voltage, W Walts-Playmobil is the man to ask, he may well have some detailed information on his website.
 
Last edited:
Greg Elmassian

Greg Elmassian

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That will work if your setup is already in 2 pieces, a power source and a throttle.

If you are working from a "all in one box" where the power and the "knob" are in the same box, it won't work.

What is the power source/controller setup?

Greg
 
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playmofire

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In Playmobil, the track power locos are up to 16v; RC is 6v on the old versions and something else on the modern yellow diesel.
 
JimmyB

JimmyB

Semi-Retired; more time for trains.
In Playmobil, the track power locos are up to 16v; RC is 6v on the old versions and something else on the modern yellow diesel.
New diesel is 6 X AA, so 7.2 v or 9 v rechargeable or not
 
OBBherr

OBBherr

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Greg, preferred controller would be the Playmobil or LGB all in one controller but separate controller and power is an option if that provides an analogue max speed solution.
 
Greg Elmassian

Greg Elmassian

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OK, so one suggestion above is not going to work for all in one controller, the one you asked about actually... it needs to go between the raw power supply and a standalone speed control... not possible if all is in the same box (not easily).

So, your options are a mechanical upper limit on the speed knob, or the simple circuit I posted to limit max voltage.

From your description, I think you want to keep this inexpensive, so I agree with the all in one controller. Do you have one already or is this still to be purchased?

Greg