Hello All - I’m dipping a toe into the DCC++ world for my dedicated programming set up. I have both an Arduino Mega and the Arduino motor shield on order. What is a good, reliable, and safe 12V 3A power supply/wall adapter to use for the motor shield? I know Amazon has tons listed - just looking for some informed advice. TIA!
I'll try and see what I'm using tomorrow but if you are really talking DCC++ you should move on to the much improved DCC++EX here and the power supply question will be answered there also. https://dcc-ex.com/ Sumner
I am actually using DCC++EX and I saw the power supplies they listed. I was just looking for some field experience. Appreciate finding out what you’re using.
Here is what I'm using. Don't have any idea where it came from as it was in a box with other power supplies I'd saved over the years. I'm N scale so started with this 12 volt power supply for the Uno based system on my test track and it has worked fine. I'm running a very early version of DCC++EX on the Arduino Uno which has worked great for my purposes. When I get the main layout to the point I can run trains I'll run a Mega (just got one that has WiFi also) with the latest DCC++-EX version. I also bought some Tam Valley boosters ( HERE ) that I'll use along with their suggested power supply for the booster ( HERE ). http://1fatgmc.com/RailRoad/3D-Printer-2/page-52.html The Arduino DCC++EX command station won't supply track power once it is connected to the boosters. Sumner
Some of the SPROGs take similar power, and the US distributer sprog.us.com offers a 12V 3A supply they provide with their systems, at a reasonable price.
I went "crazy" and purchased this one a couple of months ago: https://www.amazon.com/NICE-POWER-V...rial&sprefix=nice+30v+5a,industrial,96&sr=1-1 I like the option to go slightly higher than 12V....
Variable voltage supplies are great for bench use, but unless you can lock out the front panel adjustments (once set to your desired voltage and current limit), I don't recommend using them for fixed voltage applications. It's just too easy to bump a knob and fry something, especially when the USB port is precariously close to the coarse voltage adjust knob... Such a supply would be perfect for a "programming station" where you needed to use different voltages to install and test different scale locomotives' decoders, etc. That supply looks like a really good deal too. But for a "flip the switch and run some trains" solution, I highly recommend a fixed voltage supply.
As I mentioned I'm using 12 volts on my test track but I'd have no problem going up to 14 maybe even 15 with N scale. I think that about any decoder is OK up to 15 volts and the motor is never going to see that unless you maybe run your engine with the throttle as high as it will go. ----------------------------------------------------------------------- Digitrax recommendations ( HERE ): 3.1.1 Avoiding Heat Problems With Decoder Installations Most HO, N & Z Scale model locomotive motors and lamps are designed by the locomotive manufacturers to operate at full speed at 12 volts DC on the track. Digitrax recommends running your DCC command station and boosters at the lowest track voltage possible that provides acceptable operation.The “N Scale (12V)” setting on Digitrax equipment works for most HO, N & Z scale layouts. Some DCC systems made by other companies supply more voltage to the track and are not adjustable. If the track voltage applied exceeds the operating parameters of the locomotive and its lamps, it is possible for overheating to damage your locomotive whether you use DC or DCC. For example, running an N Scale locomotive that was designed to run on 12-14 volts on a system that supplies 12 or more volts to the track may cause overheating and damage to the locomotive, its shell and your decoder. ----------------------------------------------------------------------- When I go to using the Tam Valley boosters I bought looks like my track voltage will be a little over 14 volts although I can still run the DCC++EX command station at a lower voltage if I want since the two will be optically isolated. If I have a problem I will report back but that will be a while. Sumner
It is important to note that the "DC" that the encoder provides to the motor is not pure DC, it is PWM, for which peak voltage will be close to the amplitude of the DCC waveform (depending on the method of rectification), which will be close to the supply voltage for the DCC command station/booster. So even at very low throttle voltages, the motor would see pulses consistently higher than the 12VDC. The duty cycle would not be sufficient to provide equivalent DC voltage above 12V unless the throttle setting was pretty high (assuming that no speed-mapping was done in the decoder). I would be very surprised if the decoder would be damaged from ~15V operation. No motor damage should be expected from this, unless the train was consistently run at far above scale max speed, or with heavy load and BEMF (cruise control) enabled on the decoder (and likely at high speed). Current (generating heat from winding resistance) or speed (bearings) destroys DC motors, not voltage (until you way over the rated voltage).
