How To Make An Inexpensive DIY DC Model Train Power Pack And Speed Controller

If you are looking for an inexpensive transformer or power pack to control your DC analog trains, below are instructions for making a single cab train controller and a for a dual cab train controller.

homemade power supply The unit at the left shows a power pack with a single controller

It has a switch for forward and reverse operations.

The speed controller allows you to adjust the output voltage from 0 to the maximum voltage of your power supply.






This next image shows a power pack with which you can control two trains.






Here is a video that shows the dual cab power pack in operation.  Video


You can get all the parts to make these power packs at PolandsBest Electronics.

You should use a a fixed voltage power supply that takes  house current and converts it to a fixed DC voltage. This fixed voltage that you need varies from gauge to gauge. G-Scale trains typically run with up to 24 volts, HO-Scale is about 16 volts and N-Scale needs as little as 10 or 12 volts.

You can use anything from a converted computer power supply to a computer power supply.  These can supply 3 and more amps, more than enough for a good sized layout.

For safe operation some sort of fuse or circuit breaker is a must. If you don’t expect too many derailments or short circuits a fuse is an inexpensive option. Fuse holders can be purchased for a few dollars from Amazon, eBay and other sources. Select a fuse that is no larger in amperage than the power you are sending to the track. I like to keep fuse size to the lowest value that I can use with the trains I am running. For example, if you measure your train pulling 1.5 amps select a 2 amp fuse even if your power supply and controller are rated for 10 or more amps. I also like to purchase FAST BLOW fuses as they cut the circuit more rapidly than standard fuses.

If you find that you are replacing fuses all the time you might want to move to a circuit breaker. They do the same job as a fuse but are resettable, usually by pressing a button.

Put the fuses on the output side of the speed controller. That should have them blow quickly should a short circuit occur.

You can get all the parts to make these power packs at PolandsBest Electronics.


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