Laptop Power Bricks and Grounding (Earthing)

I hope this is the right group for this question.
On my Apple MagSafe AC adapter, it can take 100 to 240v AC 50/60 cycles.
Pretty standard for laptops. Apple's world travel kit includes ends for pretty much every country in the world. But none appear to use grounding/earthing. I have a cord that I use when I'm at home in the US with a three prong NEMA 5-15. On the end that connects to the transformer/brick there are metal contacts that contact the metal button thing on the adapter.
http://www.imagebam.com/image/cc9249124023824
in the picture above you can see the metal contacts on the three pronged cord while the smaller travel plug has nothing but white plastic.
http://www.imagebam.com/image/039f56124023825
you can see it here and the round contact on the transformer itself.
Rather than carry around that cord, I'd rather carry just the adapter and small plug. I know grounding is for "safety." Safety from what? Getting electrocuted? Static? Is there any more inherent danger to using the ungrounded plug?
When I travel outside the US, the cord always comes with me in my checked luggage. So if I run into an alien shaped outlet that doesn't like Apple's design I can use my US grounded cord with a cheap little plug adapter - of which I have plenty.
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On Fri, 18 Mar 2011 01:47:35 -0400, Justin

These things are usually double insulated and there is nothing to ground. I suspect the 5-15 is just to make you feel good about using it.
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On Fri, 18 Mar 2011 02:19:09 -0400, snipped-for-privacy@aol.com wrote:

I was wondering the same thing. I need a 12V 5A power brick for a box we're building. They come in both "2-wire" and "3-wire" varieties. I verified the 3-wire sort doesn't have the output grounded, so the third wire doesn't actually do anything. Still don't know if we need it.
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" snipped-for-privacy@att.bizzzzzzzzzzzz" wrote:

Does it have lower EMI?
Is the three wire cord easier to find than the two wire?
What is the difference in price?
Are there places that require a three wire cord for local codes?
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On Fri, 18 Mar 2011 23:28:10 -0400, "Michael A. Terrell"

I doubt it, but it's impossible to say without testing them, which is scheduled for the end of the month. I'm bringing a couple, in case the one we want to use (a three-wire) falls on its face.

Both are readily available. Neither are the IEC style, though that's another issue. I think they're called "C7" and "C8" (or "C5" and "C6", I think are the mating ends - don't remember which is which).

Same price, or close enough to make it moot.

That's the question. If so, do they ban all double-insulated gizmos?
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" snipped-for-privacy@att.bizzzzzzzzzzzz" wrote:

Some I've opened had a shield that was connected to the ground lead to prevent interference to AM radios & TVs.

The three conductor 'mickey mouse' ears?

Then I would use the three wire units, if they pass the other tests. If nothing else, the AC connector seems to be more rugged than the two wire types.

Who knows? Some of those laws are passed to protect their retarded relative's business dealings.
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On Sat, 19 Mar 2011 02:21:44 -0400, "Michael A. Terrell"

Hmm, maybe I'll choose the 3-wire, as the backup, then. I have three to choose from and I think I'll have time to do the scans on two. Chamber time comes in four-hour slots and it usually takes a couple of hours to do radiated and conducted emissions tests.

Never heard them called that, but yup! That's a good description. ;-)

That's a good point, too. Thanks. Availability is another factor. IIRC, favoring the 2-wire (DigiKey stock). I'll have to check that, too.

Agreed.
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" snipped-for-privacy@att.bizzzzzzzzzzzz" wrote:

You can pre test them on the bench with your scope. Some supplies can radiate a couple volts of RF at six inches.

I needed some recently and had to buy them on Ebay. Less than $18 for 10 of them. I heard the term on some computer group. :)

You could use the two wire as a backup part by listing it as a secondary component.

Kind of like the Sheriff's son on "Smokey & the Bandit'. ;-)
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On Sat, 19 Mar 2011 20:57:34 -0400, "Michael A. Terrell"

I doubt even they could advertise the alphabet soup certs they claim, were that the case. ;-)

They're only a couple of dollars at DigiKey.

We can list whatever combinations we want. We're doing the listing. ;-) The lab results are backup for the assertion of compliance.

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" snipped-for-privacy@att.bizzzzzzzzzzzz" wrote:

They only certified the pre-production unit. :(

Digikey wanted a credit card. E-bay takes paypal. It will be even worse, if one group gets that law passed to require all debit card transactions to be in multiples of $100.

Very few companies can get around that. Microdyne never needed it for their telemetry products, but their customers would have never bought any products with problems.
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On Sun, 20 Mar 2011 00:04:12 -0400, "Michael A. Terrell"

Well... ;-)

Which group is that? Any pointers? I can't see the banks going for that one.

It's not getting around anything (or perhaps I misunderstand you). FCC[*] is self-certified. We've sold stuff without testing. Just don't get caught selling an illegal radiator.
[*] It gets more difficult for the rest of the world. Some want bribes.
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On Sun, 20 Mar 2011 12:36:03 -0500, " snipped-for-privacy@att.bizzzzzzzzzzzz"

http://money.cnn.com/2011/03/10/pf/debit_cards_limit/index.htm
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Michael Moroney wrote:

More like an Iputz.
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" snipped-for-privacy@att.bizzzzzzzzzzzz" wrote:

Then the bean cutters start deleting parts. :(

Not the banks. I see that gfretwell already posted a link.

At one time the FCC wouldn't let you sell RF gear without their approval. I had a pile of product brochures from Pace for their Landmaster radios that were stamped, 'Awaiting FCC Approval'. Since most of Microdyne's equipment was customized for each customer, and those customers were government agencies, they were exempt.

Or they arrest your employees and charge them with spying, like China did to Microdyne when they were setting up an Intelsat earth station in China.
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On Sun, 20 Mar 2011 17:28:19 -0400, "Michael A. Terrell"

Our gear has radios (900 and 2400MHz) but they're certified separately and have their own FCC IDs. We buy them with all the approvals, at least for the US and the EU. Other countries want bribes the radio manufacturer hasn't paid yet.

There is that. I'm not planning a China trip. ;-)
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" snipped-for-privacy@att.bizzzzzzzzzzzz" wrote:

Sometimes it's better to tell them you don't sell to their country because of the corruption. If they want something bad enough, they will find a way to buy it from you. and avoid all the crooks.

The man it happened to was still working at Microdyne while I was there. The work was for a governemt agency, and they were SUPPOSED to have someone waiting for him at the airport who spoke english when he arrived to walk him through customs. The man wasn't there, and he couldn't understand what they wanted, so they dumped his briefcase on a table. The company logo was a sat dish. A guard sw it and started yelling, SPY! SPY! SPY! He was held for a few days, until the site called the company to ask why the tech hadn't arrived. They gave the information on his flight, and finally located him. The morons who locked him up didn't even report the arrest.
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" snipped-for-privacy@att.bizzzzzzzzzzzz" wrote:

Radioactive Maroon Syndrome. Glow in the dark loser. Walking night light. Ambulatory Geiger counter test source.
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