Hello 
I have an Odroid HC2. I'm looking for a power supply for it. I was thinking to buy a switching stabilized power supply, like the ones used for video surveillance. As per my Nas to be turned on a lot of hours I don't want some enclosed power supply to over heat.
You think this is a good solution?
For Odroid HC2 and a Seagate Ironwolf 4TB (I was looking for this hard drive) I think a 12V 5 A should be good right?
Thanks in advance!
12 Volt 2A should be plenty. But you might want to power other stuff as well.
I use a 12V 20A for 7 HC2, a GbE switch, a fan and a wifi mesh unit. Typically a HC2 draws way less than 2A. But when booting and/or spinning up the drive 2A may be needed. I have considered adding some form of staggered power on. To avoid having them all booting at the exact same time. An arduino and a set of SSR. Solid state relays. I got the pieces but haven't put it together... I might then be able to supply 9 HC2, an external dual drive USB enclosure, a GbE switch, a fan and the mesh unit.
https://www.amazon.de/dp/B01MRSAT39
Works fine. I got one spare, in a drawer.
No. 12 Volt and 2 Ampere is 12 * 2 = 24 Watt. That is enough for both the board and the drive during peak power usage.
Compare this with a RPi4. 5 Volt and 3 Ampere is 5 * 3 = 15 Watt. That is significantly less power.
A modern 3.5" HDD draws less than 10 Watts. An Ironwolf peaks at 7 Watts during full use writing data. Perhaps slightly more during part of a second or so while spinning up.
So you don't ever need more than 12 V 2 A for a HC2. That is more than 5 V 3 A. 24 W compared to 15 W.
In addition voltage drop due to resistance in the power cable will be lower using 12 Volt. U = R * I. So you can get away with using slightly thinner and/or longer cables if you are using 12 Volts. Voltage drop in cables is a common problem for 5 Volt SBCs. Even if you use a really beefy 5 V 5 A power supply for a RPi4, you may have difficulties delivering 5 Volt to the SBC. Because you need less than half the current for the same power using 12 V compared to 5 V, you get less than halv the voltage drop using the same cables.
If you attach an unpowered external HDD to the USB port of a RPi4, then the current need will increase. And with that the voltage drop will also increase. And the RPi4 may fail because the voltage is too low despite there being plenty of power. This is much less of a problem for a HC2 that is powered by 12 V.
So no need to scale up a PSU for a HC2 like many do for a RPI4 or other 5 V SBCs. Actually you shouldn't scale up the PSU for 5 V. You should use much shorter and thicker cables, that helps more against voltage drop due to high current use.
Your 12 V 5 A power supply would be enough for two HC2 with power to spare. You could most likely also power a fan or a (power efficient)GbE switch or a wifi AP.
My 12 V 20 A power supply would be enough for ten HC2. More if I stagger power on and disk spin up.
Sie haben noch kein Benutzerkonto auf unserer Seite? Registrieren Sie sich kostenlos und nehmen Sie an unserer Community teil!
