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Hi All

I have used an MRC power supply with 16v-4A output for my layout. Can I replace other power supplies with 13-15v output? It affects the operation of the locomotive on the layout or DCC controller of MRC ?

Thanks
 

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I'm confused about what you want to do. If you're trying to replace the power supply for a piece of equipment, you need to go like for like: 12v, 60W for one of the same rating. If, on the other hand, you just need a source of power for lights or what have you, then whatever works is fine.
 

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You may get something near the same voltage and wattage that will work in the short term, but you may also be slowly cooking things or under powering them.

It matters more than you think. Answer the questions people are asking you. If you didn't really want anyone's input and were just going to charge ahead, why did you bother asking?
 

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That's not enough current. Don't use it.
Well it kinda depends on how much current the original system was actually using. My system can run a pair of steamers with a 1.5A supply, so if OP isn't running very much then a 3A output might be enough. The lower voltage will reduce train speed and pulling power though.
 

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That's one amp less headroom. Yes, it will work until the draw is exceeded and then magic smoke could start appearing.

I wouldn't use it if it were my railroad.
 

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I kind of agree with Michael, without knowing what the supply was power before and whether it 3 amps continuous or intermittent, its difficult to really guess whether its worth while. You could try it and see, if it gets really warm, I would not use it.
 

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While the voltage output is less than optimal (if we're talking HO), the amperage throughput doesn't seem to be problematic...only limited, and that might be a good thing. If your DCC system's short detection circuitry is up to snuff (quarter test), then you'll go a tad shy on voltage and won't get the performance the engineers designed into the drive mechanism. You'll be limited to 3 amps, and I couldn't imagine the label is deceptive, a safety guide demanded by the insurance industry, which would NOT be happy with them offering 3 amps, but only at peak demand...not continuous. I'll happily stand to be corrected.



As the saying goes, if you give Johnny four apples, but he only wants one, he will only eat the one. It's the same way with current (amperage) draw. What matters more, at least for now, initially, is the voltage supplied. That spec is important. As both the above sites tell us, voltages outside the specs are not good, but the worst of the two possibilities is always going to be the higher voltage because it can accommodate a higher amperage. You can get away with slightly reduced voltages, especially for can motors. All it means is that it won't perform up to snuff, and could heat up a lot.

Anecdote: My father, now 90, ran mines all over the world in the 50's through to the 80's. At a mine in southern British Columbia, he routinely did a walkabout to see how the mill and crusher were doing. His peeve was efficiency, or in mining it's 'recovery'. How much of the minerals you have contracted to purchasers are to extracting from what is available in the ore. In the crusher, he felt the heat coming off a cone crusher. He asked the operator what the voltage was. 400 Volts. He spoke to an electrician accompanying him and asked if the voltage could be raised. Yes. Raise it to 440 and let's see what happens. They did, and within an hour the motor cooled dramatically. It was allowed to take up amperage, the food for work, more readily, more efficiently. As the site above says, motors will have less torque at lower DC voltages, and they may just burn up, unable to turn whatever is resisting them.

I'm not prepared to offer advice on how a slightly low voltage will affect the other components of the DCC system, or of a decoder and its supported electronics. My guess is...it will be somewhat innocuous. On the other side, I accidentally flipped the voltage/scale toggle on my DB150 Digitrax main control box a few years back...up...to the O scale position. I ran my layout on at least three sessions until I realized the error. I haven't lost a decoder yet...and the Super Empire Builder system ran flawlessly last night, last week, and last year.
 

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You'll be limited to 3 amps, and I couldn't imagine the label is deceptive, a safety guide demanded by the insurance industry, which would NOT be happy with them offering 3 amps, but only at peak demand...not continuous.
The power supply was made in China. That means it might put out 3A under a very specific test that the manufacturer designed to optimize what rating they could put on the label. They are under no obligations to actually meet the requirements of any of the quality-control labels that they printed on this device. For comparison, I picked up a power pack off ebay which came from China and is rated for 16VDC @3.5A. Connecting a voltmeter across the leads gives a reading of less than 0.25VDC and shorting the output won't even produce a spark. There is virtually no weight to it, so my assumption is that it's a simple buck converter without any kind of transformer. If I put a capacitive load across it, then I might see a voltage output, but as it stands the device can't even be used as a brick.

I'm just saying, the printed specs are meaningless unless the device is manufactured in a country that abides by the rules.
 

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It bears a Samsung label, so you can be confident that, unless it is entirely counterfeit, it meets the stringent specs of the company that engineered and paid for them. Where it was made is irrelevant.
 
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