Ebay PWM controller

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mattd10
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Ebay PWM controller

Post by mattd10 »

A little package arrived from ebay this morning!
Image
It is a 5-30V reverisble DC motor speed control PWM (the description name). I got it because, mainly, I was intrigued and at £7.83 with free shipping I had very little to lose!
First test I did was with some of my N gauge (I'm less worried about breaking that!) and did so by hooking up a 9v battery to it and attaching to a grubby bit of flex. It worked a treat! Nice smooth running, not the slowest speeds in the world (but thats more likely due to wheel and track condition) My next challenge is to try it in T. I need to pop to maplin to get a 3xAA battery holder and see what happens!
I intend on using this on my continuous run layout, so low speed is not essential. Its also a curiosity experient to see if an 8 quid controller from china is any good! If it doesn't work in T it will find use on a future N/OO9/O9 project anyway!
I'll post my findings when I have them and will happily post the link or any more info I can!
(Just as a disclaimer, I will buy an official T gauge PWM controller as soon as I can afford one. I'm fully aware it will be far safer and better quality...but the kid inside me just wants to try this out!)

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dkightley
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Location: Nottingham, UK

Re: Ebay PWM controller

Post by dkightley »

Matt

You'll have to measure what the full power "under load" voltage drop is across the controller. The lower the voltage the better.

If its half a volt or less, then this device could be promising.

Having said that, if the volt drop is high, then upping the supply voltage might help. Remember we're working with low voltages to start with....so a one volt drop is a very high percenatge!
Doug Kightley
Webmaster here and volunteer at the National Tramway Museum http://www.tramway.co.uk

mattd10
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Re: Ebay PWM controller

Post by mattd10 »

At full power the voltage across the controller is 8.94V from a 9.14V battery. Only a drop of 0.2V! I'm guessing that's not too bad!
I have just tested it using my original T gauge controller as the input and this gives no drop in voltage! A steady 3.94 each time.
I tried hooking it up to my track and testing it with my old 103, but it has finally given up the ghost (I tried with both controllers and neither worked) so I can't do a live test until I get a new unit (birthday less than a month away, so maybe it's finally time to get a HST?)
But it all seems promising so far! I'll get my £8's worth out of this thing if it kills me ;)


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Cleantex
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Joined: Thu Nov 14, 2013 10:02 pm

Re: Ebay PWM controller

Post by Cleantex »

I was in 2008 importing one of the first box from Japan, and you know also that the first trains from Eishindo were roadrunners.
So I tried to improve with very good result by application of the following simple circuit. On this old video you see the difference.

http://www.youtube.com/watch?v=2xgY58PZAPY

PWM-Controller with 1,5-12 Volt Input (choosable) build into a common AC/DC Adapter, I also use it for other tools like drill or mill.
Inside apart from the voltage selector everything is thrown out and replaced by the circuit. You may still choose also the polarity.
Impuls_trafo.jpg
Impuls_trafo.jpg (19.04 KiB) Viewed 9724 times
Impuls-Niedervolt_1.jpg
Impuls-Niedervolt_1.jpg (91.99 KiB) Viewed 9724 times

mattd10
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Re: Ebay PWM controller

Post by mattd10 »

Thanks for this Cleantex, looks great! May well give this a go as well! I'm still waiting for a few things to arrive before I can continue my layout so this may kill some time!!

ConnorL
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Joined: Thu Nov 14, 2013 1:55 am
Location: Chesapeake, VA USA

Re: Ebay PWM controller

Post by ConnorL »

Any updates on this PWM controller? Does it work well? Or it's slightly unstable?

mattd10
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Location: West Sussex, UK
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Re: Ebay PWM controller

Post by mattd10 »

I've not done anything since the initial tests unfortunately! Haven't had a chance to get a sensible power supply or get my hands on a new mech! May be a few weeks until I get anything concrete here, although the initial tests were promising. I attached the wires directly to the motor and it span down to very low speeds (lower than with the standard controller) so I'm hoping with a new mech and clean track we'll be in business!

Unfortunately, I'm still awaiting the arrival of some other components to carry on with my other layout which would be the test bed, so they're all relying on each other!

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