Ask HN: Constant electrocution from MacBook enough to cause You heart issues?

5 points by huntedman 4 years ago | 8 comments

Hi,

I’ve been using a macbook pro on a daily basis for the past 10 years or so. For the past 3 years or so, I’ve been using it constantly plugged in (charging) without an external keyboard/mouse. This period closely matches up with the period I’ve been having heart palpitations.

I’m an otherwise healthy individual, 28 years old, no previous conditions, athletic body. I go running 2x a week, and have a set of bodyweight exercises I perform DAILY, to keep in shape. I have never smoked or had any relatives with heart issues.

I recently quit caffeine completely, since I was having more and more palpitations daily. The symptoms have improved, but not disappeared.

Today, when my girlfriend came to pat me on my arm, she said

her: “Wow are you cold?” me: “No, why?” her: “You’re shivering” me: “Ah, no that’s because, I’m touching my laptop. I have an electric current traveling through me.” her: “OMG???”

And that’s when it hit me: I’m constantly being electrocuted on a daily basis by my laptop. I’ve grown accustomed to the small current that’s traveling through my body for at least 8 hours a day. I even adjusted my sitting posture, so that I’m always in full contact with my laptop, in order to avoid a partial contact (to avoid THAT painful sting).

I know that many of you know about this constant weird buzz, when for example You gently run a finger over your macbook, whilst it’s charging.

It can’t be healthy… right???

Are any of YOU experiencing similar symptoms or are in a similar situation?

Do You know of any research on effects of small current on the human body, over a prolonged period? (unlikely)

Are any of You encountering anxiety, tension in chest, near the heart ?

scantis 4 years ago |

It is at least plausible, that you could run an AC current over your arms and over your chest. This can cause a stimulus to your nervous system if the current is high enough to overcome the action potential.

A tingling sensation, muscle spasm and aching would be the cause for low levels of current and prolonged exposition.

But since you found the culprit, you would be easily be able to mitigate your exposure. Either by wearing latex or rubber gloves or proper grounding of your device, which should not shock you btw.

Above the action potential you muscles will contract and your nerves will give stimuli, which can cause tension and anxiety.

If you feel the shock sometimes you are definitely above action potential.

There is another threshold above the action potential, which will cause irreversible damage, heart failure or death. A residual current device is usually installed with your circuit breakers to prevent residual current above this threshold.

iamtoomas 4 years ago | |

OP here (new acc, because previous one has anti-procrast enabled:)

It's not a shock, that's comparable to a static electricity discharge, when touching a door handle for example.

And the "shock" I feel when I partially touch my laptop, is comparable to someone constantly pulling on one strand of your body hairs. It's a constant pain that happens when You baaarely come in to contact with the laptop with for example Your forearm (the skin on the palms is too thick to feel it)

It's actually a common theme with macbooks. A former coworker actually pointed it out to me.

"Ugghh, don't you hate it when you slide your finger across your laptop and it's giving you that buzz?"

I was like "What are you talking about? It's just the brushed aluminum feel?"

He told me to unplug the charger and try again. And Holy moly indeed the buzz stopped.

scantis 4 years ago | | |

My wording was maybe a bit bad, but this really sounds like AC current leakage. When you feel it, it is above the action potential, therefore activating your nerves and muscles.

This could be due to improper grounding or faulty components. This is not normal and shouldn't be!

It can cause all kinds of symptoms, but the general consensus is, that if it is below the dangerous threshold of around 30 mA, there will be only discomfort but no permanent or irreversible damage.

Discomfort is lightly said, but can have a huge impact on your quality of life. Please do something about this and maybe complain to the vendor. Even though this is not seen as health risk.

There are some studies suggesting in vitro damage for all kinds of cells at low levels of current, you as a complete system will be very resilliant to this.

ksaj 4 years ago |

I'm really late on the reply chain, but hopefully you'll see this.

I wonder if there should be an inductor coil on the power cable. It sounds like some AC is getting through, and an inductor (which is essentially an electro magnet) basically shaves it off.

That's what the mystery box or tube is that you see on some other adapters and sometimes on accessory cables for things like keyboards with built-in USB ports.

Basically the higher the current, the more magnetized it becomes. Magnets are polar, which makes it behave a bit like a one-way resistor so AC can't flow through.

lax4ever 4 years ago |

Have you stuck a volt-meter to your laptop to see if it is actually running a current through the body of the laptop? If it is, might be worth having the laptop serviced.

iamtoomas 4 years ago | |

Unfortunately no. And I'm currently traveling and don't have access to one.

and It's actually a "feature" of macbooks in general, not this particular one.

I mentioned under another comment:

That A former coworker actually pointed it out to me.

"Ugghh, don't you hate it when you slide your finger across your laptop and it's giving you that buzz?"

I was like "What are you talking about? It's just the brushed aluminum feel?"

He told me to unplug the charger and try again. And Holy moly indeed the buzz stopped.

lax4ever 4 years ago | | |

I would seriously recommend getting it serviced. I have 3 MacBooks in my house right now and none of them do that.

FaisalAbid 4 years ago |

Try using a keyboard and mouse for a week and see if your symptoms get better.