DC power for motors

[jesselingard]

Hi,

So i am preparing to install point motors to my layout, but i need a way to get the DC power from the AC power of the  mains  

Anyone got any ideas, would be very happy to hear them!

Thank!

[2e0dtoeric]

That is a very vague question, and seems to be in the wong threads, too.

You should NOT have mains voltage anywhere near a railway. If you have, you have done something VERY wrong!

The mains supply should go to a transformer, either a 'wall-wart' or a stand-alone unit. That converts the electricity to a safe dc level, of usually about 16v. That is then fed to the controller (s) which in turn control the trains.

You also seem to be asking about point motors. It depends on what kind you have, and there are several!

If you mean the basic solenoid, you need to send your mains to a transformer, (again), but this one delivers 16v AC. That goes to a Capacitor Discharge  Unit (CDU), then via the switches - to the point motors.

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I urgently suggest that you do  LOT more reading, before you connect anything to anything else, or you may do yourself and others serious harm.

[96RAF]

Welcome to the forums...

 

Have a Google for Brian Lamberts website where he explains amongst many other things how to rig up the various types of point motor.

 

You didnt say which point motors you are using as different types are wired differently. Solenoids, slo-mo motors or servos. Also you talk about DC powering them but post this question in the DCC section, so we need to know if you intend operating them by manual switching or via DCC.

 

I use an old analogue controller Aux AC output for my CDU operated solenoid motors. DCC operated motors are generally powered directly from their accessory decoder. Sevos need their own controller.

 

Rob

[Chrissaf]

Point motors need very high currents to operate robustly and reliably. So you need a power supply that gives out a voltage of between 15 and 19 volts DC with a current capability of 3 amps or better. Laptop power supplies can be bought quite cheaply that meet this criteria.

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However if you add a CDU (Capacitor Discharge Unit) in line with the output of the power supply, then the high current requirement for the power supply can be reduced to a lot lower value (say about 1 Amp or even less) this makes just about any 15 to 19 volt DC power supply suitable.

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The CDU takes in a much lower input current, stores the power in its internal capacitors. This high power is then available to operate the point motors when called for. Thus it is the CDU that is providing the high current required by the point motors and not the attached power supply.

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Including a CDU has an other advantage, due to the way they work it is technically impossible to damage or burn out the solenoid coil of the point motor (subject to the CDU not going faulty). Without the CDU, it is very easy to leave the power connected too long to the point motor and start to heat it up due to the high current it is passing.

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Because (due to the inclusion of a CDU) you now only need a Laptop Power supply with a lower current capability, then this makes sourcing a suitable supply even cheaper.

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Although, point motor instructions usually say that the product is operable on supplies as low as 12 volts, I would recommend that for robust operating reliability you should use a supply no less than 15 volts DC and preferably 19 volts.

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These clickable links give more information on power supplies, wiring up point motors and CDUs.

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http://www.thehobbyshed.co.uk/point-motors

http://www.brian-lambert.co.uk/Electrical.html#Motor

Laptop power supplies (ebay).

Example CDU (other brands are available).

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All links open in a new Tab or Window.

[Chrissaf]

I have added a comprehensive reply, but it has been sent for checking to the profanity police. I have looked at what I wrote multiple times and cannot find the offending word that has triggered the auto-capture.

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It will probably appear once Adam has OK'd it.