# Can I supply a device rated for 1A with 15A power supply? [duplicate]

I'm talking about a big difference between output current of the power supply and rated current of the device here. Would it burn up?

## marked as duplicate by Dave Tweed♦Mar 24 '18 at 14:33

• No the device will take up what it needs. – Transistor Mar 24 '18 at 14:31
• If the grid can supply 10kA surges and you apply a 0.1A clock to AC outlet will it burn up? – Sunnyskyguy EE75 Mar 24 '18 at 14:40
• unregulated power supplies don't reach specified voltage until specified current is drawn, so in that case you would have way too many volts. But, at 15A, it must be a regulated switching supply and you're fine. – dandavis Mar 24 '18 at 17:04

You have an electrical supply to your house. How many amps can it supply. My main fuse is rated at 63 A.

You have a light bulb. It's rated at 20 W. How many amps will it draw. Answer: $I = \frac {P}{V}$ so that's about 0.1 A in 230 V land or 0.2 A in 110 V land.

I'm talking about a big difference between output current of the power supply and rated current of the device here.

Me too.

Would it burn up?

No. As in the case of the light bulb, the load will draw the current it requires and that's all.

You may want to consider limiting the current to a safe value in the event of a fault. Add a 2 A fuse in-line and you should be fine.

The power supply provides up to 15 amps. This does not mean that it has an output of 15 amps, always. The power supply will give the current requested by the device up to a maximum of 15 A.