Have the recommended Elegoo Mega 2560, EX-MotorShield8874, and the Makerfab wifi shield. They also recommend the Amazon "LEDMO Power Supply, Transformers, LED Adapter, 12V 5A 60 Watt Max" so my question is if I wanted to increase the voltage for DC operation to 15 or 16v my understanding is (from solar install) -> the higher the volts the less Amps/Watts needed and/or drawn? Another adjustable unit is rated -> "DC 3V 5V 6V 9V 12V 15V 16V 18V 19V 20V 24V Variable" at "3A 72W" so would the Amp rating between 60W and 72W be sufficient / comparable? I need to get away from the unreliable voltage of the TYCO transformers - I 'tested" them too late! -but would like the higher volt options if running EX-DC mode only? (TRUTH BE KNOWN I burned up my new DCC decoder by using too much voltage (Sumner WARNED me!) but Walthers has agreed to replace it under WARRANTY)
Power (Watts) = Volts X Amps. It looks like that adjustable voltage power supply will provide a maximum current of 3 amps and maximum power of 72W (you cannot exceed either limit), thus the 72W maximum power only applies at 24V (at which 72W is 3 amps). Modern DC power packs vary the effective (average) track voltage by varying the duty-cycle (on/off time ratio) of a full-supply-voltage square wave. DCC-EX does this too, in DC output mode. DCC systems generate a full-voltage AC (square wave) that changes pulse widths to communicate with each locomotive decoder individually. The decoder both rectifies (converts to DC) the DCC waveform for decoder power, and interprets the command embedded within the waveform to determine the speed (motor voltage) requested for that decoder address. Like modern power-packs, the decoder generates a variable PWM waveform for the locomotive's motor voltage. At either 12V or 15V, if you are running anywhere near maximum throttle, the trains are running way beyond maximum scale speed (unless they are Shinkansen!) For N scale, I recommend a 12V max supply voltage. For HO scale (only) you could go up to 15V, but the only difference would be top end speed, which is probably excessive scale speed anyway. Also, the higher the DCC supply voltage, the more the motor brush wear. N scale motors have smaller brushes.
So 72watts (max) \(at) 16volts would equate == to 4.5amps available? Grandson and I like to race on inner/outer loop so . . .
No, there are two limiting conditions, neither of which may be exceeded: 3 Amps & 72 Watts. In practice, you will reach one of those limits before you reach the other. Regardless of the voltage, the max output current is 3 amps. The maximum rated output wattage is sometimes (often?) only reachable at the maximum output voltage, to avoid reaching the current limit beforehand. P.S. Always choose the inner loop when racing!
Thanks BigJake found another adjustable at "Wattage Max 5A" will go with it instead. P.S. Six yr old would be upset always let him win
6amp power-supply arrived today tested it and voltage is SPOT ON. Comes with various adaptors which don't need fits CommandStation, center-positive, perfectly! Different brand decoders have varying "voltage limits" the generic ESU in Walthers is 18v max! Noticed the Soundtraxx max is "7V – 22V"? Sent Burnt out decoder for "warranty service" hoping it arrives there in one piece Spoiler: Walthers Repair Department Out for Delivery MILWAUKEE, WI 53218 March 10, 2025, 8:18 am
