Metal/aluminium vibrations.

pokerking · 21 Dec 2018 at 19:59

Hi I've got a geobook3x it's an aluminium/metal body, I get some static vibrations throughout the casing of the laptop when plugged in.

I have done the old Google search and it seems MacBooks can have the same issue.

The power lead does not have an earth pin, it's plastic.

I'm no good with electronics but would buying an different charger with a earth pin resolve the issue?

It's been bought in the purple shirt place so my rights to return are none existent it seems.

Hope that makes sense!

EsaT · 21 Dec 2018 at 22:38

If you mean that happening when plugged to wall using power adapter there could be couple possibilities:

Often that happens when device needs grounded wall socket, but there's no ground wire or contact in socket.
As result certain capacitors in EMI filter form voltage divider, making ground reference of power adapter float half way between live and neutral. (and output ground wire is connected to that)
Using grounded wall outlet removes that tingling.
But if devices is meant to be used without safety ground EMI filter really has little use for those particual capacitors. (which do nothing useful in that case)

Or power adapter literally leaks some AC through to its output ground wire, which then leads it to chassis of connected to device.
That could be serious safety risk.
As that seems to be some very cheap laptop, I wouldn't wonder any if its AC adapter is some genuine China Export trash.

If you have multimeter you could measure voltage between AC adapter's output connecter ground and safety ground pin of wall socket.
If it's from those EMI filtering components present, then voltage should be half the AC voltage.

pokerking · 21 Dec 2018 at 22:58

Hi thanks for the reply. Here is the laptop

https://geo-computers.com/geobook-3x-13-3-laptop-hd-intel-pentium-n5000/

I had no idea it came with a very poor PSU. You are correct in saying it's a very cheap PSU 12v 2amp. Looking on eBay it looks just like a £2 LED strip PSU. There will be no grounding/earth pin in the plug.

If the laptop is not plugged into the PSU the static vibrations stop, or if my feet are not touching the ground when it is plugged into the PSU, ie laptop on sofa with feet up there is nothing there.

I've found a few good PSUs but these seem to be 12v but 5a and 60W. Would something like this work?

It deffo is because of the very poor PSU.

gEd · 21 Dec 2018 at 23:29

pokerking said:
Hi thanks for the reply. Here is the laptop

https://geo-computers.com/geobook-3x-13-3-laptop-hd-intel-pentium-n5000/

I had no idea it came with a very poor PSU. You are correct in saying it's a very cheap PSU 12v 2amp. Looking on eBay it looks just like a £2 LED strip PSU. There will be no grounding/earth pin in the plug.

If the laptop is not plugged into the PSU the static vibrations stop, or if my feet are not touching the ground when it is plugged into the PSU, ie laptop on sofa with feet up there is nothing there.

I've found a few good PSUs but these seem to be 12v but 5a and 60W. Would something like this work?

It deffo is because of the very poor PSU.

as long as the voltage (and the connector) is correct it should be fine. that fact that this PSU has a higher power is a good thing.

Laptops are not earthed (in the same way that radios aren't) which is why they typically have a 2 pin "8" connector.
https://en.wikipedia.org/wiki/Appliance_classes
In Europe, a double insulated appliance must be labelled Class II or double insulated or bear the double insulation symbol (a square inside another square).

If it's in warranty, I'd take it back, irrespective of what coloured shirts they wear.

pokerking · 21 Dec 2018 at 23:37

gEd said:
as long as the voltage (and the connector) is correct it should be fine. that fact that this PSU has a higher power is a good thing.

Laptops are not earthed (in the same way that radios aren't) which is why they typically have a 2 pin "8" connector.
https://en.wikipedia.org/wiki/Appliance_classes
In Europe, a double insulated appliance must be labelled Class II or double insulated or bear the double insulation symbol (a square inside another square).

If it's in warranty, I'd take it back, irrespective of what coloured shirts they wear.

Thanks, I will try a laptop style PSU one with the brick and a correct UK power lead rather than this

http://oi65.tinypic.com/iekmmb.jpg

The laptop is 1 day old, stuck a m.2 SSD in there and it's a decent little machine for £200 just want to sort this issue out.

EsaT · 22 Dec 2018 at 10:16

pokerking said:
The laptop is 1 day old, stuck a m.2 SSD in there and it's a decent little machine for £200 just want to sort this issue out.

That would have likely gotten some refurbished business laptop with mostly better everything, except more or less worn battery.

Some electrical safety authorities might be interested in testing that AC adapter if it's sold by UK shop.
Not sure what's UK's equivalent for Finnish Tukes.

Just few days ago in Finnish tech forum one user measured some Silvercrest branded USB charger giving 70V AC from ground of output.
He first noticed problem from getting shocked when answering to phone connected to charger after coming out from shower.
(humid/wet skin has lot lower resistance)
He measured also handfull of other such chargers and one had 24V in output ground.
(others 0 to 5V)

And Apple certainly uses very cheap manufactured stuff, so I wouldn't wonder similar problems in their chargers.
Unless it's their own bad design. They're very experienced in making and selling crap designs under shiny surface.

There's simply no trusting to safety of cheap whatever brand stuff.
Like lack of PFC being the smallest worry in this, with no actual grounding of metal case, while lacking plastic insulation sheet under PCB:

Wouldn't wonder any if also physical separation and insulation strength between primary and secondary fails to meet safety requirements.
(insulation must keep 3kV to input separated from low voltage output)

If you just Google you'll find cases of people getting electrocuted by trash AC adapter leaking AC through.
https://www.thejournal.ie/woman-electrocuted-usb-charger-1540800-Jun2014/
https://www.dailymail.co.uk/news/ar...wearing-headphones-phone-plugged-charger.html

gEd said:
Laptops are not earthed (in the same way that radios aren't) which is why they typically have a 2 pin "8" connector.
https://en.wikipedia.org/wiki/Appliance_classes
In Europe, a double insulated appliance must be labelled Class II or double insulated or bear the double insulation symbol (a square inside another square).

Class II applies only to AC adapter.
Laptop itself is Class III appliance and should never see any voltage remotely close to mains voltage.
That's why they can have metal chassis instead of always needing full plastic/insulating material shell.

pokerking · 22 Dec 2018 at 11:20

EsaT said:
That would have likely gotten some refurbished business laptop with mostly better everything, except more or less worn battery.

Some electrical safety authorities might be interested in testing that AC adapter if it's sold by UK shop.
Not sure what's UK's equivalent for Finnish Tukes.

Just few days ago in Finnish tech forum one user measured some Silvercrest branded USB charger giving 70V AC from ground of output.
He first noticed problem from getting shocked when answering to phone connected to charger after coming out from shower.
(humid/wet skin has lot lower resistance)
He measured also handfull of other such chargers and one had 24V in output ground.
(others 0 to 5V)

And Apple certainly uses very cheap manufactured stuff, so I wouldn't wonder similar problems in their chargers.
Unless it's their own bad design. They're very experienced in making and selling crap designs under shiny surface.

There's simply no trusting to safety of cheap whatever brand stuff.
Like lack of PFC being the smallest worry in this, with no actual grounding of metal case, while lacking plastic insulation sheet under PCB:

Wouldn't wonder any if also physical separation and insulation strength between primary and secondary fails to meet safety requirements.
(insulation must keep 3kV to input separated from low voltage output)

If you just Google you'll find cases of people getting electrocuted by trash AC adapter leaking AC through.
https://www.thejournal.ie/woman-electrocuted-usb-charger-1540800-Jun2014/
https://www.dailymail.co.uk/news/ar...wearing-headphones-phone-plugged-charger.html

Class II applies only to AC adapter.
Laptop itself is Class III appliance and should never see any voltage remotely close to mains voltage.
That's why they can have metal chassis instead of always needing full plastic/insulating material shell.

All very good information thank you! I will try a laptop style charger, would something like this stop the issue I am having?

http://oi67.tinypic.com/2q0mz3d.jpg

EsaT · 22 Dec 2018 at 15:24

pokerking said:
All very good information thank you! I will try a laptop style charger, would something like this stop the issue I am having?

http://oi67.tinypic.com/2q0mz3d.jpg

Properly built AC adapter certainly shouldn't have any mains voltage leak to its output ground.

But anything bought from Chinese based websites of web, or some cheap completely China based brand are risk of safety deficiencies.
Those cheap factories can basically make first "sample" batch according to regulations and then cost cut all safety.
https://webarchive.nationalarchives...c.gov.uk/media/137366/60600_Booklet_proof.pdf

pokerking · 22 Dec 2018 at 16:45

EsaT said:
Properly built AC adapter certainly shouldn't have any mains voltage leak to its output ground.

But anything bought from Chinese based websites of web, or some cheap completely China based brand are risk of safety deficiencies.
Those cheap factories can basically make first "sample" batch according to regulations and then cost cut all safety.
https://webarchive.nationalarchives...c.gov.uk/media/137366/60600_Booklet_proof.pdf

I appricate the help and info thank you. What type would you recommend?