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The_Customer
22nd June 2005, 12:30 PM
at my office here there is alot of carpet and whenever i have been walking around my office and come back to my powerbook i get shocked from the static electricity. Juts wondering if there is a chance of me frying anything in it cause i know you have to ground yourself if your working inside a computer but what are the chances with the powerbook?

applecollector
22nd June 2005, 04:24 PM
i don't think so!

the_OM
22nd June 2005, 06:16 PM
I've done it all the time in the year and bit since I've had my powerbook, and nothing has ever happened.

Although I have had a logic board replaced, but I don't think that was the problem.

Actually, now that I mention it, it could have been the problem.

Yep, definately was the problem. Electric Shocks will fry your logic board.

In all seriousness though, I don't think you have anything to worry about, its happened a few times to me and my powerbook is still alive.

Ozi
22nd June 2005, 06:59 PM
I think a lot of the shock would disipate on the case too. Static electricity (and hence the time-honoured tradition of working on your computer nude) is only really a problem when you are handling the delicate internal parts: motherboards, RAM chips, the other bit with that stuff, you know. :)

gelfie
22nd June 2005, 08:34 PM
The stuff on the inside will be insulated from the enclosure anyway. Otherwise it would be shorting itself out.

The_Customer
23rd June 2005, 09:19 AM
gelfie your a smart man...

Squozen
23rd June 2005, 11:08 AM
If your environment is that bad, I'd still investigate some kind of grounding mat you can put below your chair to ground you before you sit down at your computer. It may not damage your PowerBook, but I can still think of better things than being given an electric shock every time I touch a computer.

steph
20th September 2005, 12:56 PM
Has anyone noticed 12" powerbooks retaining electrostatic charge while connected to the mains electricity?

It happens nearly all the time when connected to the mains, and gets worse as the laptop heats up. i took it to the biggest mac shop in Kuala Lumpur, the chinese guy tested it extensively and could find nothing wrong. then i went back last week to buy a headset and he told me he had bought the same laptop as me and was experiencing the same "shocking"

This forum discusses externally generated static. in my case (and the mac shop guys case) the powerbook itself is generating the static charge and releasing it into the nearest human body.

My environment is irrelavent, i may be on ceramic tiles, lino, carpet, sitting on a sofa or at a table, it happens anywhere.

The only solution I have found so far is to disconnect it from the mains and use it running from the battery.

My suspicion is that the powerbooks contain a design flaw in that some moving part in them is building up static electricity and the only way to discharge it is via the nearest and largest ground, which is almost always a humans arm while typing and touching the aluminium case.

Apple seem not to care, even though I have advised them. Perhaps experiencing an electric shock would encourage a more positive attitude :)

Galumay
20th September 2005, 02:16 PM
very interesting! i have noticed the same thing with my PB, i have tiles with only a small rug in the lounge room so i dont think it is static either.

i get the shock on the underneath of my lower arms/wrists when using the keyboard. it feels like it comes from between the grey plastic edge and the aluminium panel on the flat, top surface.

at first i thought it was the hairs on my arms getting 'pinched' !! but i am convinced it is a small electrical discharge. my PB is also on mains power most of the time.

it does not do it all the time - its not doing it now. i live in the tropics so maybe humidity is a factor?

Insanely
20th September 2005, 02:18 PM
Shouldnt having the pb plugged in stop any damage since it earthed anyway?

pipsqeek
20th September 2005, 02:28 PM
Originally posted by The_Customer@Jun 23 2005, 09:19 AM
gelfie your a smart man...
Not always right dude.

FYI, Gelfie is a chick. :)

pipsqeek :thumbup:

jerrah
20th September 2005, 02:36 PM
I get 'zaps' from my work powerbook too.

I thought it was static but I don't zap on anything bar the powerbook. If I've been away from it, I gingerly earth myself on it before starting typing again, but I've tried touching various other metal things, laptops etc and never had a zap.

applecollector
20th September 2005, 03:39 PM
I have noticed on my iBook DUAL USB that sometimes when i have it on my lap a rather strong electric current goes through the left side of the metal hinge.

Galumay
20th September 2005, 04:42 PM
my wife also says she gets a shock from the PB in the same way!

Senna
20th September 2005, 05:34 PM
I get shocks on my legs from my 500 MHz Dual USB iBook when metal surrounds under the rubber feet touch my skin.

It only happens when the power adapter is plugged in.

jerrah
20th September 2005, 05:36 PM
This all sounds a bit worrying, I don't think we're likely to get a lethal shock but still!

LCGuy
20th September 2005, 08:11 PM
I really wouldn't worry about it, the only ways you'd get a lethal shock are from either:

a) If you open up the display and touch the inverter board, or a cable going to or from the inveter board while the machine's turned on and running, and even so, it won't kill you, i've been zapped by an inverter before and it gave me a helluva wake-up call, but apart from a 1mm burn mark on my finger, I was fine.

or

B) If you open up the power supply and touch its parts

Squozen
20th September 2005, 08:46 PM
Earlier Apple laptop power supplies are ungrounded (you'll see that they only have two prongs on the plug), which is why you're getting shocks. You can buy a replacement power supply that's grounded and the problem will go away.

Galumay
20th September 2005, 08:58 PM
ok, help me here, apple sell me a product that gives me electric shocks, this is due to them supplying an unearthed power supply cable, so to fix this apple will SELL me a replacement, earthed power lead!!??

is this correct? (rhetorical question really)

spargo
20th September 2005, 09:50 PM
Ok, this is my electric shock status, with my 13 month old, 15" G4 1.5 Ghz PowerBook.

When I purchased it last year, it came with the standard white transformer power supply box, a 2-prong clip-on socket, and a 3-prong (earthed) clip on 1-1.5m extension lead, giving me the option of either connecting the transformer box straight into the wall socket, or having it half-way along the cable between the PB and the wall socket (I hope you get my drift). Both of these are interchangable with iPod chargers and Airport Express boxes.

So this is what happens when i'm using my PB in its various powered arrangements:

1. Battery only - no shocks/tingles

2. Powered/Charging with the clip-on 2-prong socket, straight into the wall/powerboard - I receive some minor tingles from it, assumably because the small clip-on socket only has 2-prongs and therefore doesn't have an earth for the transformer. So the machine must be earthing where required through me!

3. Powered/Charging with the 3-prong (earthed) clip-on 1-1.5m extension lead - I receive no tingles at all, assumably because the 3-prong clip-on extension lead socket has 3-prongs and therefore DOES have an earth connection for the transformer.

If people are concerned, then they should probably use the socket with 3-prongs rather than the 2-prong one. Seems pretty crazy to only have 2-prongs on one socket, when the transformer it connects to IS capable of earthing via a 3-prong socket, AND you're using a metal cased electrical applicance..

spargo
20th September 2005, 09:54 PM
Originally posted by galamay@Sep 20 2005, 11:58 AM
ok, help me here, apple sell me a product that gives me electric shocks, this is due to them supplying an unearthed power supply cable, so to fix this apple will SELL me a replacement, earthed power lead!!??

is this correct? (rhetorical question really)
Hey galamay - Didn't your PowerBook come with a longer cable that has a 3-prong socket, as well as the clip-off 2-prong small socket?

Mine did (as explained above), but things may have changed when your newer model PB was released..

Can anyone else with a new model and/or older model confirm this?

What did your's come with Ozi? It's the same model as mine. Both a 2-prong & 3-prong extension lead?

Georgina EG
20th September 2005, 11:23 PM
Does it happen using iBooks, and how would it affect someone with a pacemaker? The 3-pin plug sounds the right way to go.

pb12lover
20th September 2005, 11:28 PM
my new powerbook 12' (2 weeks old) came with both the extension cord with 3-prongs and the 2-prong adapter. like spargo, i only get tingles when using the 2-pronged adpater

jerrah
20th September 2005, 11:38 PM
To be honest I don't recall which connector I'm using on my powerbook at work. I'll check tommorrow. :thumbup:

LCGuy
21st September 2005, 12:10 AM
Originally posted by Georgina EG@Sep 20 2005, 11:23 PM
Does it happen using iBooks
I wouldn't think so, as iBooks have a plastic exterior, whereas the PowerBooks do not.

helloroto
21st September 2005, 12:46 AM
Originally posted by LCGuy@Sep 21 2005, 12:10 AM
I wouldn't think so, as iBooks have a plastic exterior, whereas the PowerBooks do not.
it does happen with iBooks, especially when using the 2-prong thingy, you will normally recieve shocks from either the battery removal thingo and the display opener thingy

Cheers,
Roto :D

PS Excuse the miss terminology

jerrah
21st September 2005, 09:19 AM
How about that - I was using two prong. Now using the 3 prong cable and I'll report back if the shocks have stopped.

jerrah
21st September 2005, 10:57 AM
Completely zap free since installing the 3 prong, I'm suprised I didn't think of it earlier but I assumed it was static electricity rather than electricity leaking from the laptop. :ph34r:

I feel more relaxed now, no longer on edge with the occasional zap to keep me on my toes.

Ozi
21st September 2005, 11:02 AM
Originally posted by spargo@Sep 20 2005, 09:54 PM
What did your's come with Ozi? It's the same model as mine. Both a 2-prong & 3-prong extension lead?
Yep spargo: two pronged one where the poweradaptor "brick" plugs straight into the power point, and the three-pronged extension one. It makes sense that the 3 prongs is less prone to causing electric shocks, as the third prong is "Earth" and presumably disipates this static electricity. :)

Mystery solved. :P Good work guys.

forgie
22nd September 2005, 04:29 AM
Ok, I just did some testing with my new G4 iBook...

I tested the AC voltage between the display side bolts and earth (taken from the chassis of my PC). This is NOT static electricity. Static electricity is DC voltage, this is AC, which gives a 'burning' sensation. I just got that 'burning' sensation when I touched the little bold on the side of the iBooks display when I had the 2-prong adapter in.

3-prong: 80mV. This is perfectly normal.
2-prong: 110V. This is not normal!

I know a fair bit about electronics, but it's far too late to be analysing the implications of this measurement. Let me reaffirm, this is NOT static electricity. Anyone who is in the know in regards to earthing/floating earths/etc, now is the time to fill us in!

spargo
22nd September 2005, 07:30 AM
Originally posted by forgie@Sep 21 2005, 07:29 PM
Ok, I just did some testing with my new G4 iBook...
Holy crap forgie! that info rocks!!! Thanks for the efforts and contribution.. and this is on an iBook, let alone a metal PowerBook!

I'll be sticking to my 3-prong extension cable thanks very much, and will only resort to the 2-pronger when I desperately need to charge on the road, and when I WON'T be touching it during this time..

like forgie said, if anyone else can contribute it'd be appreciated.

jerrah
22nd September 2005, 08:41 AM
Originally posted by forgie@Sep 22 2005, 04:29 AM
3-prong: 80mV. This is perfectly normal.
2-prong: 110V. This is not normal!
110V!

I'm happy to report a full day since I switched to 3 prong and I haven't had a single zap from my powerbook. And I'm feeling much less stressed. :P

Georgina EG
22nd September 2005, 08:56 AM
Does it happen with non Apple portables, and if not, why doesn't Apple fix the problem rather than leave it to zapped users to attach an external cable with a 3-pin plug?

forgie
22nd September 2005, 02:19 PM
Also, I didn't mention last night (early this morning :)) that according to my multimeter the AC voltage was at 50Hz - in other words it's mains leakage current. I'm surprised in a way that this doesn't set off the earth leakage detector when you get a shock, but I digress. Chances are, the impedance/resistance (effective AC resistance) is high enough that you can get a mild shock, but nothing ever enough to do any serious damage (you need a low resistance and a high voltage to get a high current, and current is what actually does the damage). I can work out the impedance with a bit of experimenting and testing, but I'll have to recall the methods used in my Power Measurement lab from second year electrical engineering..... I'll keep you all posted.

forgie
22nd September 2005, 02:30 PM
Originally posted by Georgina EG@Sep 22 2005, 08:56 AM
Does it happen with non Apple portables, and if not, why doesn't Apple fix the problem rather than leave it to zapped users to attach an external cable with a 3-pin plug?
In Australia I believe it's illegal to use a 2-to-3-prong adapter (or an earth-lift adapter). In the US people going for darwin awards use them all the time to fix earth loops and other grounding problems. I know of no other device which has an option for either a 2 or 3 prong plug, it just doesn't make sense. I have no definite knowledge as far as the legality, but I think apple may be in breach of Australian power safety regulations. Usually a device is either double insulated (plug packs) and transformer based, or it's earthed, and switch-mode based (this goes for all 'brick' power supplies). The transformer designs have no electrical connection between mains and the output, so they don't need an earth. The switch mode supplies generally have a small connection of some sort, but there are many, many switch-mode power supply designs, and which one apple has used is a mystery to me.