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lukadjanelidze
02-18-2016, 08:57 AM
Hello everyone,

I've recently bought G751JY-WH71 (WX), and while charging i noticed that the metal back on laptop is kind of vibrating when i touch it. i use adapter for 3 pin plug (american one) to 2 pin (europian) plug. can this be a problem?

thanks in advance for any help.

ROG_HARDCORE
02-18-2016, 11:57 AM
Hello everyone,

I've recently bought G751JY-WH71 (WX), and while charging i noticed that the metal back on laptop is kind of vibrating when i touch it. i use adapter for 3 pin plug (american one) to 2 pin (europian) plug. can this be a problem?

thanks in advance for any help.

This is the problem when the power plug are not grounded. Must use 3 pin plug for equipment safety in long-term purpose.
Use 3 pin plug please.

Dr4g0n36
02-18-2016, 02:52 PM
You could easily Exchange terminal cable with one EU with 3 pin. check also if you power strip (eventually if you have one) has 3 pin and not 2 or the problem is just a little more down.
55746

EttoreA
02-18-2016, 06:43 PM
You could easily Exchange terminal cable with one EU with 3 pin. check also if you power strip (eventually if you have one) has 3 pin and not 2 or the problem is just a little more down.
55746

Sorry, but this one is Type L and it's used almost exclusively in Italy and Chile.
If the 2 pin plug is Type F (used anywhere in Europe and Russia) then it is a grounded one.

Dr4g0n36
02-18-2016, 08:23 PM
Sorry, but this one is Type L and it's used almost exclusively in Italy and Chile.
If the 2 pin plug is Type F (used anywhere in Europe and Russia) then it is a grounded one.
oh you mean schuko adapter (german type). this plug has 2 normal pin for electricity and 2 sided terminals that is ground cable. So is already 3 pin plug type.

lukadjanelidze
02-18-2016, 09:56 PM
oh you mean schuko adapter (german type). this plug has 2 normal pin for electricity and 2 sided terminals that is ground cable. So is already 3 pin plug type.

i live in georgia(not state) and we have these types of sockets and plugs here, and i wonder if there are some kind of adapter to also ground.
55748

Dr4g0n36
02-18-2016, 10:25 PM
i live in georgia(not state) and we have these types of sockets and plugs here, and i wonder if there are some kind of adapter to also ground.
55748

According to your photo you don't have ground cable in the wall. The 2 ways are to replace wall plug or buy an UPS .

lukadjanelidze
02-18-2016, 10:33 PM
According to your photo you don't have ground cable in the wall. The 2 ways are to replace wall plug or buy an UPS .

thanks a lot for advice.

JustinThyme
02-18-2016, 11:14 PM
Flip the plug 180 in the socket, you have reversed polarity, hot where neutral should be and vice versa.

Three prongs on laptop power supplies is a relatively new thing. I still have a bunch laying around without it. Couldnt find a schematic with the ground but penciled it in, you can see where the buzz comes from, Top input shoud be hot and bottom neutral.

55752

lukadjanelidze
02-19-2016, 07:24 AM
Flip the plug 180 in the socket, you have reversed polarity, hot where neutral should be and vice versa.

Three prongs on laptop power supplies is a relatively new thing. I still have a bunch laying around without it. Couldnt find a schematic with the ground but penciled it in, you can see where the buzz comes from, Top input shoud be hot and bottom neutral.

55752

thanks you very much. besides that, can this buzzing cause any serious problem for laptop? i was running laptop for 3 days before i noticed this problem and nothing seems to happened except probably cpu temp hitting 86C max.

cdma2k
02-19-2016, 12:49 PM
thanks you very much. besides that, can this buzzing cause any serious problem for laptop? i was running laptop for 3 days before i noticed this problem and nothing seems to happened except probably cpu temp hitting 86C max.

wrong polarity or bad grounding happens all the time.When you buy a house, it is always a good idea to buy a CIRCUIT TESTER
to check the polarity of every outlet in the house.

lukadjanelidze
02-19-2016, 02:26 PM
the funny part is that i asked my friends to try and tell me if they had the same vibration feeling when touching metal back and all of them said that im crazy and im making everything up :D

clockworksatan
02-19-2016, 02:43 PM
I've felt a similar thing before on the brushed aluminium panels of HiFi equipment, so I know the exact feeling that you're talking about - but I doubt that it's worth worrying about.

lukadjanelidze
02-19-2016, 03:30 PM
I've felt a similar thing before on the brushed aluminium panels of HiFi equipment, so I know the exact feeling that you're talking about - but I doubt that it's worth worrying about.

i've forgotten to mention that this "vibration" doesnt happen when laptop is not charging. anyway, i hope that its a minor problem.

JustinThyme
02-19-2016, 04:16 PM
wrong polarity or bad grounding happens all the time.When you buy a house, it is always a good idea to buy a CIRCUIT TESTER
to check the polarity of every outlet in the house.

Codes vary from country to country and the only way you can test polarity 100% is with a meter and a ground source. If you look at the OPS sockets and plugs they are not even polarized like whats in the US now and everything could be wired correctly yet you are still able to connect devices in a reverse polarity configuration.. At one point even the US did not have polarized sockets and plugs. Now the Neutral connection is physically larger than the hot so you cant reverse polarity. Grounding in the US now is the most strictly enforced and hardest to understand part of the code book. The only time you have problems here now is when you buy a house that is either old or had someone add outlets that does not know how to do so and did not get it inspected.

@ OP did you try to reverse the plug in the socket 180? 90% of the time that's all you need to do. If you understand electronics and how charging circuits work its perfectly understandable why it would only happen with reverse polarity when it charges by looking at the schematic I provided. If you did reverse it and still have the problem its in your power brick, not grounding.

lukadjanelidze
02-19-2016, 05:11 PM
Codes vary from country to country and the only way you can test polarity 100% is with a meter and a ground source. If you look at the OPS sockets and plugs they are not even polarized like whats in the US now and everything could be wired correctly yet you are still able to connect devices in a reverse polarity configuration.. At one point even the US did not have polarized sockets and plugs. Now the Neutral connection is physically larger than the hot so you cant reverse polarity. Grounding in the US now is the most strictly enforced and hardest to understand part of the code book. The only time you have problems here now is when you buy a house that is either old or had someone add outlets that does not know how to do so and did not get it inspected.

@ OP did you try to reverse the plug in the socket 180? 90% of the time that's all you need to do. If you understand electronics and how charging circuits work its perfectly understandable why it would only happen with reverse polarity when it charges by looking at the schematic I provided. If you did reverse it and still have the problem its in your power brick, not grounding.

yes i tried but it didnt work. i still feel vibration but only when its charging. i'll probably have to replace power brick.

EttoreA
02-19-2016, 08:41 PM
Yes, maybe your power unit got a relatively large leakage current to grounded parts of your ROG notebook - chassy or exposed metallic parts. If that's the case unearthed plug/wall sockets at your home do not help for sure.

The question is, did wall sockets at your home get earth wires ? You said you live in Georgia so, I honestly don't know how things come there. In Europe or US, unless the device has been designed for double insulation - which is not the ROG notebook case - the earth wire to plug/socket is a must.

You may possibly see - if you ever have a chance to check it - what happens if you wire the ground pin of the ROG plug to an home radiator (for central heating) or to an oven pipe as these harnesses should be at earth potential.

Weirdoutworld
02-19-2016, 09:25 PM
Yes, maybe your power unit got a relatively large leakage current to grounded parts of your ROG notebook - chassy or exposed metallic parts. If that's the case unearthed plug/wall sockets at your home do not help for sure.

The question is, did wall sockets at your home get earth wires ? You said you live in Georgia so, I honestly don't know how things come there. In Europe or US, unless the device has been designed for double insulation - which is not the ROG notebook case - the earth wire to plug/socket is a must.

What are the hardware risks of non-grounded outlets in the US? Also I'm kind of let down to learn ASUS rog power brick isn't double insulated... Little bit scary living in an old house...

EttoreA
02-19-2016, 09:47 PM
What are the hardware risks of non-grounded outlets in the US? Also I'm kind of let down to learn ASUS rog power brick isn't double insulated... Little bit scary living in an old house...
The same hazards as the rest of the world; getting zapped at worst :)
However, I think you shouldn't worry for ASUS rog too much; more plastic than metal.
Rather it's your washing machine or freezer at your home if you live in old house with no grounded outlets.

JustinThyme
02-20-2016, 02:29 AM
The ground wasn't added to prevent shock, it was added to connect a path for fault current if the mosfets take a dump. With no ground they will simply cook and melt the housing. Add a ground and a shorted mosfet will cause the breaker to trip or fuse to clear. The term doubled insulated is reserved for appliances and power tools. All it means is there are two layers of insulation between live parts instead of one.

As for non grounded outlets in the US the above applies to the laptop brick, it will cook. The housing is completely non metallic and non conductive. There are still hundreds of thousands of homes in the US without a grounded system. Is it a concern, yes but look at it this way. People went a very long time without ground outlets. Same applies, its there to provide a path to ground for fault current.

As for the OP try taking you laptop elsewhere and try it before buying a brick. One other culprit could lie in your electrical system of your dwelling. If the main neutral line is not bonded to earth ground this could cause it too.

cdma2k
02-20-2016, 02:40 AM
The same hazards as the rest of the world; getting zapped at worst :)
However, I think you shouldn't worry for ASUS rog too much; more plastic than metal.
Rather it's your washing machine or freezer at your home if you live in old house with no grounded outlets.

In some cases, floating ground might also casue audio hum

EttoreA
02-20-2016, 10:54 AM
Yes stray currents may create low frequency noise in some cases.

For those who are interested or want to learn, this link is sufficiently accurate:

https://en.wikipedia.org/wiki/Ground_(electricity) .

Official safety requirement are stated by IEC 61010/UL-61010 standards, 'Safety requirements for electrical equipment'.

lukadjanelidze
02-20-2016, 12:34 PM
i took laptop at asus service center today and they said that there's nothing to fix inside the laptop or power brick and that this "vibration" is kind of normal thing.

cdma2k
02-20-2016, 01:40 PM
asus is not responsible for faulty grounding or old style outlet

JustinThyme
02-20-2016, 03:43 PM
In some cases, floating ground might also casue audio hum

Please explain what a floating ground is and how it causes audio hum. I'm familiar with induced electrical hum caused at the frequency of the power supply, in the US we refer to it as 60 cycle hum and is caused more my poor circuit design using cheaply sourced components than anything else. However Tulane University did not cover anything about floating ground in the undergraduate or Masters courses in electrical engineering and Stanford failed to cover it in the Masters curriculum for Electronics engineering.


Yes stray currents may create low frequency noise in some cases.

For those who are interested or want to learn, this link is sufficiently accurate:

https://en.wikipedia.org/wiki/Ground_(electricity) .

Official safety requirement are stated by IEC 61010/UL-61010 standards, 'Safety requirements for electrical equipment'.

Wiki page is partially correct. Never trust it a WIKI page for accuracy as anyone can write them, this one in particular sourced other wiki pages and undergraduate papers making it not all that reliable. Like I said, its partially correct.



i took laptop at asus service center today and they said that there's nothing to fix inside the laptop or power brick and that this "vibration" is kind of normal thing.

Did the issue present itself at their facility while plugged into their electrical system? If yes then it is most likely a faulty brick and could possibly be an issue in the charging circuit in the laptop itself but highly doubtful as what you are getting is AC introduced through the brick onto the DC negative. If it did not then I can say with a reasonable amount of certainty that the problem lies within your electrical system and has less to do with a safety ground that does nothing but provides a path for fault current that should not be there in the first place and everything to do with the current carrying grounded conductor, Neutral, not being grounded at the source of service entrance on your dwelling or possibly a bad connection of its connection via the grounding electrode conductor to the ground rod or in some instances where allowed by local code the main water line. Electricity does some strange things. The strangest Ive seen personally that stumped the local utility companies, the fire dept and several local electrical contractors was a home where several appliances emitting a very loud hum and producing an electrical shock when touched. First thing they did was cut the main breaker to the dwelling. One would think that will solve it right? Wrong! Next the cut they power line to the home, surely that will solve it right? Wrong! Eventually I was called first thing I noted was that all the appliances that were humming, and it was LOUD, were connected to a water source. I went to the water main out front and drove a rod in the ground about 10 ft from the meter, this is about 100 ft from the house at this point, and measured from the water meter to the ground rod, 120VAC. Walked next door and saw a tree limb across the service entrance of the house next door. Told them to cut the power to that house. I hear across the fire dept raidio "Silence is Golden". The tree limb put one hot line to the neutral, that houses neutral was bonded to the water line and the other house was not, it was grounded with a ground rod. Current followed the water line to the ground rod in the house next door. After that incident the local code no longer allows grounding the current carrying grounded conductor, neutral, to the water line.

Julskey
02-20-2016, 05:01 PM
Best I can think of a floating ground is ground connection in ships. Hehehe. Ground which is not earth ground. Seriously, I think floating grounds are the common connection in appliances which are not connected to an earth ground. There are some countries - like the Philippines which use 220 Volts and some parts in the Philippines have balanced lines 110-110 (line to line) and some have line to ground (220-0). Most old houses here have only two prong outlets. Individual appliances must have their own ground, done by running a wire from an appliance to a metal rod buried in the ground. Most of the time, people ignore this, and when there is an electrical fault in the appliance, you get an electrical shock. If it were grounded, current will flow from the chassis to ground and will trip the breaker. Now, we have three prong outlets standard.

Regarding the hum. This is true for improperly grounded high gain amplifiers ie Electric Guitar Amps. The guitar cords will act as antenna picking up radio noise and AC interference and gets amplified by the amp. If the amp has good grounding (earth ground), and the audio cables used are shielded, all the interference are routed directly to ground instead of the high gain inputs of the amp.

cdma2k
02-20-2016, 07:02 PM
another example of a floating ground is ground connection in space shuttle?:p
most of the hums in audio component are caused either by poor grounding layout in audio component or faulty grounding outlet.

JustinThyme
02-20-2016, 07:08 PM
An appliance that is grounded by running it to a separate ground rod that is not part of the electrical system as a whole misses the intended point and does not provide a path for short circuit protection to trip the breaker.

First Ive heard of with the Philippines having phase to phase power system, their codes state otherwise as it being a 220V line to grounded conductor, ie neutral. My two Marshall amps do not have induced RFI interference however Ive seen it in the economy versions like Crate that will do it grounded or not, this goes back to the statement I made about design and components and of course non shielded cheap cables will introduce hum also regardless of the grounding as the unshielded cable becomes part of the pick up and will happen no matter what amp you have and grounded or not. The electrical hum is eliminated by introducing and EMI filter at the input.

Ships and aircraft including the space shuttle use whats called an insulated Neutral system as you cant get a ground on a ship. You don't bond anything as it can result in a shock hazard when the hull becomes juiced. Even looking past that it causes corrosion by introducing an unintended anode. We ran into issues with UPS systems operating correctly on shipboard applications and had to make a specific design that is 480 only with isolation transformers in and out to match the particular ships distribution system and use a transformers and capacitors to form a pseudo neutral via an LC network as UPS systems do not create 480, they create 3 phases 277 to neutral separated by 120 degrees.

Grounding and bonding is one of the most misunderstood things in an electrical system and one of the largest hard to understand parts of the NEC code book. Try reading the part just regarding swimming pools, that's enough to fry your brain!

Julskey
02-21-2016, 04:38 AM
An appliance that is grounded by running it to a separate ground rod that is not part of the electrical system as a whole misses the intended point and does not provide a path for short circuit protection to trip the breaker.

First Ive heard of with the Philippines having phase to phase power system, their codes state otherwise as it being a 220V line to grounded conductor, ie neutral.

Well most parts of the Philippines have line to ground (220-0) two leads from drop wire, but only one insulated and the other bare. In the city where I live in, we have 110-110, also 2 leads, both insulated. If you drive a steel bar to the earth and make this your ground, you get 110V from one of the lines to ground. So, we can power 110V appliances by using only one lead wire and ground.

Circuit breaker used in our system has two poles. If any of the two live connections get in contact with the chassis which is properly grounded, the CB should trip since it will form a short circuit from line to ground. Thus proper grounding is important for the safety of personnel.

Sorry to be getting OOT already. Happy Sunday.

JustinThyme
02-21-2016, 02:55 PM
Sorry, you are not getting the point. I'm trying my best to explain advanced concepts used in engineering with elementary terms. Connect your devices and run your grounds as you wish. Why bother taking the advice of a licensed EE with 30+ years of global experience that works for one of the largest electrical conglomerates on the planet? If you get zapped or something catches fire you will have something to reflect on.
Best of luck in your endeavors!


55815

Julskey
02-21-2016, 03:56 PM
I see what you mean. The breaker may not trip because of possible ground resistance from grounding rods and pose threat of electrocution.

JustinThyme
02-21-2016, 05:12 PM
Well, sort of. The ground of the appliance must meet the ground of the distribution system for the breaker to trip. Otherwise with a separate ground the fault current is trying to flow from the distribution panel to the point of fault then to its ground source, through the earth then to the distribution systems ground and back to the breaker panel to complete the path. Look at the goofy drawing of stickman standing in water, now erase the blue ground going back to the panel and make the puddle of water the alternate ground rod. It gets much deeper in commercial and industrial applications when people bond to ground at different points and create ground loops but I'm not even going to attempt explaining that here. Bottom line is there is to be a single grounding point/neutral bond for each separately derived power system. There are two ratings on all breakers. One is fault current or KAIC rating that determines when it will trip on fault current such as a short circuit. The other rating is on overload which is nothing more than a bi-metal switch in the breaker that when it heats up it releases the trip mechanism. This is why you can run a 20 amp breaker at 20 amps often for an extended period of time and it never trips where others will trip more readily and all will trip more readily if they have been run at capacity for extended periods. Our lovely wives like to test this theory in bathrooms by having a curling iron plugged in while running a hair dryer. Often they work fine for years then start tripping all the time and the poor guy that goes to fix it for them has to listen to "well it worked fine before" As an engineering rule any circuit should never be run at a constant load exceeding 80% of its rated capacity. When calculating feeders for ampacity and over current protection you always take the full load and multiply it by 125% then use the wire and breaker rated at or the next level up. Example 20 amp circuit should never run a constant load of more than 16 amps.

lukadjanelidze
02-21-2016, 05:55 PM
so to find the cause of this i should check grounding in my house. if not, than the problem is with power brick. i also forgot to mention that here is georgia we use 220V instead of 110/120V as it is in america(?). so can this also be a culprit?

JustinThyme
02-22-2016, 03:04 AM
The voltage difference doesn't matter, one of the two conductors is still a mistral and grounded or supposed to be grounded. I wouldn't go digging into your homes electrical system first. I would try the machine somewhere else first, maybe several of the second place shows the same issue. If it doesn't do it anywhere else and you have flipped the plug 180 with no avail then it's definitely in your premises wiring. I do not recommend anyone who is not properly trained, licensed and qualified to mess with electrical systems. Too easy to lose your life if you don't know what you are doing. I see professionals leave behind wives and children over stupid mistakes. Then if you survive that part did you do it right and not create a fire hazard? Anything else I say go for it and re do your plumbing etc but don't mess with electricity of you are not a professional.

lukadjanelidze
02-22-2016, 07:00 AM
The voltage difference doesn't matter, one of the two conductors is still a mistral and grounded or supposed to be grounded. I wouldn't go digging into your homes electrical system first. I would try the machine somewhere else first, maybe several of the second place shows the same issue. If it doesn't do it anywhere else and you have flipped the plug 180 with no avail then it's definitely in your premises wiring. I do not recommend anyone who is not properly trained, licensed and qualified to mess with electrical systems. Too easy to lose your life if you don't know what you are doing. I see professionals leave behind wives and children over stupid mistakes. Then if you survive that part did you do it right and not create a fire hazard? Anything else I say go for it and re do your plumbing etc but don't mess with electricity of you are not a professional.

thanks again for advice. i'll charge laptop somewhere else, maybe in another house.