Response to Austrains' announcement of a C30 tank and C30T
An Announcement from Austrains - SDS acquisition
Connecting loco and tender - Hornby Top Tips
Trainorama 830 class 847 review
Under the Portuguese Sun - Tree planting
Bachmann new GWR Earl Class review
Reconnecting with a childhood hobby
James May urges nation to 'save Hornby' as shares plunge 62%
Hornby boss quits after third profit warning in five months
Statement from Ixion Model Railways Ltd
Every once in a while there is a need for something a bit more than the 1-2 Amps of DCC power that the typical DCC++ combination of the Arduino plus motor shield can deliver. With a separate H-Bridge driver board and your Arduino Uno or Mega2560 you can put out a DCC signal with 15 Amps of power. Let’s see how you can do it.
15A FET H-Bridge Driver
I have detailed building a DCC++ base station in my article in the March, 2017 issue of Model Railroad Hoobyist, DCC projects using the Arduino http://mrhpub.com/2017-03-mar/online/html5/?page=204 As built as described, this assembly is limited by the 2 Amp rating of the Arduino motor shield. There is a tested, compatible equivalent H-Bridge driver (Amazon: Dual Motor Driver Module Board H-bridge DC MOSFET IRF3205 3-36V 10A Peak30A Peak 30A https://www.amazon.com/Liobaba-H-Bridge-IRF3205-Controller-High-Power/dp/B07KW9H12F/ref=sr_1_3 or ebay: 3V-36V Dual Motor Driver Board Module H-bridge DC MOSFET IRF3205 Peak 30A https://www.ebay.com/itm/253945326185 ), which you can use to directly substitute for the motor shield. Cost is generally between $15-20, sometimes cheaper.
It has a peak current rating of 30 Amps, and most rate it between 10-15 Amps continuous use, but I have not run it up that high. There are no heat sinks for the two rows of Field Effect Transistors that are the actual H-Bridges. Their metal tabs must not be shorted together.
You will also need a pretty hefty power supply for this too. A short protected, well regulated power supply is a good idea. Try something contained like this from Amazon.com: 12V 20A 240W AC/DC Power Adapter with 5.5x2.5mm DC Plug and 2.1mm Adapter https://www.amazon.com/LEDwholesalers-Power-Adapter-5-5x2-5mm-3262-12V/dp/B074GGMD5J/ref=sr_1_5 or perhaps: DC 12V 10A 120W Power Supply Adapter Converter Regulator https://www.amazon.com/BINZET-Adapter-Converter-Regulator-Flexible/dp/B00Z9X4GLW/ref=sr_1_5 .
Connections are shown in the diagram below:
Jumper or solder the connections to the Arduino with pin headers. The DCC connections can be made with heavy copper wire. You do not need the Arduino motor shield to use this board.
Now for all the warnings:
Ten to fifteen Amps is a lot of current! The is NO SHORT CIRCUIT PROTECTION on this board, and yes, I have already destroyed one myself. Adding fuses, circuit breakers, or DCC power protection devices are all really good ideas. If you run this at the high end of its range, be prepared that those small metal fins are likely to get hot. You cannot simply add a common heat sink to them all without insulating all of the fins (on the FET’s).
You can easily operate this with a 8-22 Volt supply voltage. To achieve the nominal 14 Volts on the track for DCC for HO operation, you can use a 15 Volt supply, but most DCC decoders I have used will operate with this arrangement with a 12 Volt supply. Much lower and you are asking for trouble. Remember too that many HO keep alive devices will self destruct above 15 Volts on the track. The same, single supply will feed the H-Bridge DCC++ uses for the programming track. I do not personally use DCC++ at all for programming decoders of any sort. I use these for supplying power and control off the rails as a separate DCC bus for layout lighting and animation. In this manner, with no exposed connections, the likelihood of a short circuit on the DCC bus drops dramatically (until I make another goof along the way!).
I hope some modelers find this useful. Appropriate comments and suggestions are always welcome.
More Scale Model Animation at http://model-railroad-hobbyist.com/blog/geoff-bunza
More Scale Model Animation videos at
Home Page: http://www.scalemodelanimation.com/
This article first appeared on model-railroad-hobbyist.com
About this website
Railpage version 3.10.0.0037
All logos and trademarks in this site are property of their respective owner. The comments are property of their posters, all the rest is © 2003-2019 Interactive Omnimedia Pty Ltd.
You can syndicate our news using one of the RSS feeds.