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how to make a 2 to 3 prong adapter ground with my 2 prong only outlets
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It all depends on whether or not you have lightning storms where you live. There are other sources of surges, but these are the worst IMO. Last year my boss' tv and audio equipment got fried due to a lightning storm. And he has breakers. Surges can enter the grid at many points - they don't always originate at the power station.
I'm not talking about irregularities, or voltage fluctuations, or small surges. You don't need to worry much about these so much in industrial/modern countries. I'm talking about fast surges with decent potentials, like from lightning storms. While many devices have surge protection and even reverse polarity protection to deal with normal occurrences, few will protect you from lightning surges if they manage to reach the device. We had several units (industrial controls) with surge and reverse polarity protection installed on a field in Texas a few years back where ~2/3's of them blew from a nearby lightning storm (the bypass capacitors fried). It's difficult in some cases to protect against this - it really starts at the facility level with lightning rods connected to earth ground to redirect the energy.
You're missing my point. Some of these PSU suppliers may not have tested and certified their PSU's the right way, and just assembled CE marked components together and skipped testing/certification on a finished assembly level (even though they are marked as such). I don't have any direct experience here, on the consumer market, but it's not paranoia, it's from my experience on the job (industrial markets), and to me, it's not worth risking a $2,000 laptop, or any other equipment in your house (HDTV, audio, etc.) just because it has a "CE Mark" on it. I work with UL, CSA, FM, CE Mark and a few others. Trust me, you should see some of the things I see...I also participate in a couple of engineering forums every now and then - one time, there was an engineer from some company out there asking this same question - "can I use CE marked components and skip PSU testing on my company's product?". Several people told him no, he still had to test at the assembled level, but who knows what he did. I'm sure his PSU provided a certain level of safety even if he didn't, but I wouldn't bank my wallet on it (or my life), and that's all I'm trying to say. And the general question "if I use R/C components do I still have to test...?" comes up every now and then, over and over.
There are always exceptions, but in general, that manufacturer's product still has to meet all requirements relative to electrical safety, regardless of whether or not he's using a PSU from someone else who is pre-approved. The only thing that buys the manufacturer is he doesn't have to worry about component level requirements, which is why it's always good to buy/use Recognized Components. It also helps that the manufacturer doesn't have to design a PSU from scratch, but his device (and that PSU) will still be tested at the device's level for electrical safety and I know test lab engineers that have seen failures on this level even though the critical components of the PSU were pre-approved. Sometimes an OEM just doesn't use the right component/PSU for the application and it can fail a radiation or immunity test, such as a surge or fast transient/burst. Now, we don't have to worry much from reputable companies like Apple, but on the other hand, if it comes from some obscure company, you might want to give it a thought. The term "you get what you pay for" applies here
Guys, it's always a good idea to protect your equipment in your homes. Surge protectors are cheap. Your equipment is not. Many of us have thousands of $$$ worth of equipment in our homes. Do the math. And keep in mind that insurance will replace your hardware, but it can never replace your data (some external hard drives still plug into the wall - I wonder what kind of protection these small devices have). While travelling, if you don't have a surge protector (who carries one on vacation?!) you're ok to plug into the wall, but if there's a lightning storm over head or nearby, I'd shut my equipment off and unplug it from the wall (not everything, just tv/computer and anything else that's expensive).
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Wait, maybe I'm oversimplifying this, but if you don't use the extension cable and just plug the brick directly into the wall doesn't it only have two prongs to begin with? Wouldn't that imply that the third prong is not needed? Sorry if I'm completely lying though...
True. The OP hasn't said whether he lives on a farm or in an urban area. In an urban area I'd expect the chance of this to be much lower.
I know - we covered that.
No, you're missing the point. Apple is the world's largest computer company. Reputational risk from mis-testing equipment would cost it millions. Apple PSUs will have been tested to death. This is not a case where you should let your paranoia loose!
The problem is that you haven't addressed the OP's original question.
He's in an older house without available 3 pin sockets. Should he:
- Run two pin, without a surge protector (as the SP requires an earth)
- Try to wire his own earth by running a wire from a 2 to 3 pin adaptor to something metal.
I think the first option is the safer. How about you?
The solution to this is to have multiple backups and never have them all wired up at the same time. You should do this anyway, whatever the status of your local electricity supply, your use of 2 pin or 3 pin, your use of a surge protector.
I live in a sort of urban area, it is hard to define, I don live on a farm, but in an older neighborhood with 1950's military style housing. My home & a few others in my neighborhood are along a canyon.
There is no heater or heating in my home, & the walls are not insulated, I am in southern California. we do have ceiling fans. There are no pipes near my room, so if I made my own earth, I would have to somehow have a piece of metal or pipe set up under my desk.
what would help is if someone could show me some photos and or step by step directions of how I could do my own earth, & the order & steps I would set it up to avoid shock & blowing a circuit breaker. I need to know exactly what the grounding wire or what type of wire, & metal to use.
Yes, that is the correct question I am asking, whether to just go all 2 pin, or try to wire my own earth with a 2 to 3 prong adapter.
I dont have my external hard drives on all the time, but it varies, one day I may have one on for 1-4 hours working with content, the next maybe just 10 minutes.
I'm hesitant to recommend something without being there, plus home electrical wiring is not my specialty. My recommendation is he should call an electrician. Until then, I wouldn't worry much, I would just shut off and unplug any expensive equipment during lightning storms.
Edit: mmm, he could run a surge protector into a 3 to 2 prong adapter, then tie the ground to a pipe that goes into the ground (plumbing or run your own), that should do it and you wouldn't worry as much about unplugging anything during storms, but like I said, I'm not an expert here - you want to make sure you use the right adapter and wire gage.
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As I understand it the chief reason for adding the third wire in 110 volt systems was to prevent electrical shock. Back in the day most power tools: drill motors, saws, etc., and most appliances, were made of metal. If the current operating the device you were using leaked voltage into the metal housing of the equipment, and say you were standing in a puddle of water at the time (this actually happened to me once), you could get a bad shock because you became the ground. The extra ground wire was attached to the metal housing to stop this from happening. I know of no other reason for it's existence. Since most tools, appliances, etc., are made of plastic these days, in many cases, these tools, appliances, come with two prong cords.
I have lost two or three electronic items from electrical surges, but not over the power lines, it came in over the phone line.
I have lost two or three electronic items from electrical surges, but not over the power lines, it came in over the phone line.
Right about the "nub", wrong about the Magsafe.
The two outermost connections in the Magsafe are Negative, and hence ground, the next two are the positive supply, and the center connector is a 1-Wire bus for talking to the electronics in the Magsafe-plug, and controlling the LED color.
// Per.
Wrong. I have repaired a lot of these supplies, and yes, there is no contact with the metal post when measuring with a DC voltage.
The power supply input filter employs X and Y capacitors, there is an Y capacitor from neutral to ground, and an Y capacitor from live to ground. Hence the half operating voltage on the ground terminal, relative to ground when ground is not used. This is the "buzzing" you feel when touching the computer.
// Per.