DC Power Supply Amperage

[sci4me]

Hi all. I am working on a project that will use about 4.8 amps of power. I am currently looking for a power supply for it. I want something like this: http://www.adafruit.com/product/658. My question is how much extra is acceptable? I assume that that PSU is pretty overkill right? Would 5 or 6 be okay?

[Zero999]

Yes more current is fine.

The only possible problem is if there's a short circuit and the wiring is too thin to take the current, in which case a fuse is a good idea.

[rdl]

Often the cheaper switch-mode power supplies will have "optimistic" specifications. I have for example, a 9 volt 1 amp supply that works pretty well up to about 700 mA, but trying to draw much more than that causes the voltage to drop significantly. I would say using a 10 amp rated supply to get 5 amps is a probably a good place to be.

[AmmoJammo]

I spent an hour trying to get an oldish touchscreen LCD panel to do anything!

It would power up, but never display an input signal..... I replaced all the electrolytic capacitors, as the screen was getting on a bit, and had spent a fair bit of its life in a vehicle...

Turned out, the 12volt, 2amp power supply was dropping to 9volts with a 1amp load, so the screen was never powering up properly...

Tried it with a 12volt, 1.5amp supply, and it worked fine...