I would like to build a mini PC.

I have an ASRock Q1900DC-ITX motherboard.

This board don't have the regular ATX 20/24 pin power connector.
It have a 9-19V DC power connector for laptop PSUs.
This PSUs just have an 'euro-plug', 2 wires.

The ATX PSUs have a 'safety plug' with 3 wires (grounding) - so the PC case is grounded.

Because of the electromagnetic radiation from inside of the PC and for to protect the hardware inside for it and other radiation, I need to ground the PC case?
1 wire of a power cable connected to the PC case and to the ground pin of the power wall plug?

Or this will destroy the hardware?

Thanks.

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It's designed to go in a case such as the ones Gigabyte use for their Brix PCs.


The case itself provides the necessary shielding to stop EMI (Electro Magnetic Interference) from occurring.
Devices such as these are considered Double Earthed, and actually connecting one to ground, unless it specifically has a connection on it to do so, can actually be quite hazardous.
In the case of these systems, that's not likely to be the situation (due to the very low voltages). But unless it specifically says it must be connected to earth, then don't.

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Grant
Darwin NT

The reason you earth a AC power point is because both pins are live on AC current so there needs to be a earth .

http://amasci.com/amateur/whygnd.html

this is a bit long but does explain why you Earth a AC current

DC does not work the same and is much safer and the - wire is a earth

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The reason you earth a AC power point is because both pins are live on AC current so there needs to be a earth .

Well technically no. One should be "Live" and the other neutral. The neutral line should be the same voltage as the ground line, but don't bet your life on it. Faulty building wiring could put a dangerous voltage on the neutral, and still allow appliances to function normally.

The ground wire is mostly a safety measure. If there is a wiring fault in your appliance, and the phase somehow gets connected to the case. Again the appliance may work, until you touch the case and get 230 volts up ya.

Now those laptop type PSUs get around this by effectively being "double insulated" There is no direct electrical connection between the mains wires, and the DC output. They are physically isolated by a transformer in the PSU. Even with some messed up building wiring there is no physical connection between that and the DC side of the supply.

So from the safety side of things there is practically no risk.

From the RF side of things, a Faraday Shield works pretty well, even if it's not earthed. The metal box keeps in most of the high frequency RF, even no matter what. There may be some low frequency stuff that leaks, but laptops and mini PCs all seem to be able to comply with the FCC regs for RF noise.

Now connecting the case to a ground wire will do no harm. It's electrically isolated from the mains remember, so all that does is make sure it's at the same electrical potential as the ground peg outside your house. But it's a bit pointless, it wont help anything else.

Ian

Yep Ian that why i put the link there it explains it in detail .

I bet you would not be game to touch the so called neutral wire ? and in reality yes it is spose to be neutral but in theory no read the article on the link.

the earth also stops dc currents from static elctricy from building up in the wires of a ac current again read the link

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The ground wire is mostly a safety measure.

Yep, entirely so.
If a device requires an earth connection, it must have one to be safe. If it doesn't require one, then it doesn't need it.

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Grant
Darwin NT