7 ms·

It probably should have been more than 3 hours given that you likely mean "voltage" not "amps". Before everyone jumps on me, "it is the amps that kill you, not

It probably should have been more than 3 hours given that you likely mean "voltage" not "amps". Before everyone jumps on me, "it is the amps that kill you, not voltage", I understand electricity quite well and in this context, saying something like "handling high amps in a university" is almost certainly not what was taught.

philistine 4y ago
Also, it's not electronic safety, its straight up electrical safety. There are no electronics in a magnetron.
- cuteboy19 4y ago
  Even with power electronics we still say electrical safety
  - elif 4y ago
    It was a class on embedded electronics and robotics. There are more hazards in electronics than merely electrical hazards. e.g. exploding capacitors, toxic fumes, etc.
- kragen 4y ago
  A magnetron is a vacuum tube which works by swirling space charge around. Vacuum tubes are "electronics"; the word "electronics" was originally invented to distinguish vacuum tubes (where it matters that the charges are being carried by electrons) from previous electrical devices such as relays, resistors, condensers, motors, generators, and inductors, where you can pretty much ignore the nature of the charge carriers.
- robonerd 4y ago
  Surely the magnetron itself is an electronic device.
raldi 4y ago
Rather than admonishing everyone for wondering the obvious question, why not just explain your reasoning?
- shkkmo 4y ago
  High amperages are really only dangerous (in terms of electrocution) with higher voltages. As voltages get low enough, our bodies' resistance means that there won't be enough current passing through you to hurt you. The dryness of the contact point makes a big difference (several orders of magnitude), but even with wet hands, it is pretty much impossible to hurt yourself with < 12 volts. The risks with low voltages and high amperages are from shorts causing rapid heating.
- throwaway9870 4y ago
  Current flowing through your body is what kills you. But it doesn't flow through you just because it is a high-current supply (think car battery for example). It flows through you because the source voltage divided by your impedance is what controls how much current flows through you. Impedance is the general concept for resistance and basically indicates how current and voltage are related. The higher the impedance, the less current flows. Wearing rubber gloves would increase your impedance from hand to hand significantly. So while high current does kill you, what causes it is high voltage. What is considered high? Depends on your impedance (ex. are your hands sweaty or dry?). When dealing with high-current systems, there are safety procedures and concerns, but they are generally different than high-voltage. The systems I have dealt with are more about burns than electrocution. For example accidentally shorting out a fork lift battery can be spectacular in a bad way.
  - iso1631 4y ago
    There's no particular safety concerned when you're playing with hundreds of kilovolts in a typical school. You need it when the thing you're messing with has the capability of delivering a lot of amps.
    - timpattinson 4y ago
deleted 4y ago
[deleted]
xxs 4y ago
I dont know what they did in the uni, I thought it was some wielding or power delivery (CPU and GPUs nowadays deal with 200A+)... So I honestly thought it was high amps, all of them are proper fire hazard. But you are right, likely it was high voltage.
tarsinge 4y ago
Maybe they meant high voltage amps
hedora 4y ago
Once I charged a 1F (not a typo) capacitor with either a AA or 9V battery (can't remember), then touched the leads. Youch!
- throwaway9870 4y ago
  You must have charged it through some step up device, otherwise the max voltage on the cap is the battery voltage which isn't going to shock you.
  - BenjiWiebe 4y ago
    Maybe they pinched the leads together between their fingers. That could be painful.
elif 4y ago
I'm glad you assumed a very limited scope of danger being direct electrocution death because in my class I learned there are many compound forms of electrical accident. To quote NEC textbook: "Even low-voltage installers can still experience unsettling shocks, especially if they are working in an unsafe environment, such as if they are ungrounded or standing on a wet spot,” Johnston said. “While it’s unlikely that such shocks will cause serious injury by themselves, they certainly could literally knock someone off balance, which could be a real safety risk if an installer were standing on a ladder. “In addition, an arc in a low-voltage system has the same potential for igniting explosive materials as one in a 120-plus-volt system. Chapter 5 of the NEC provides rules for installing electrical wiring of any voltage in a hazardous (classified) location, specifically those locations with high concentrations of flammable or combustible liquids, flammable or combustible vapors, conductive and combustible dusts, and so forth.”
elif 4y ago
It's also possible for low voltage shocks to cause your hand muscles to seize the hazard and be unable to release it. In fact, my TENS unit, specifically designed to cause muscle contraction, runs on 9V. Edit: ah... I see a throwaway account was used, so you will never have to confront your mistake. I wish these were banned.
- xxs 4y ago
  I cant see how 9v dc can shock you aside touching the leads with tongue... or using any step up electronics. As a kid we used to test batteries voltage with the tongue, 9V had a distinctive bite, compared to 4.5V. Even today I can tell the output voltage of a multimeter (in its ohm mode)
elif 4y ago
Lastly, I would encourage you to consider tasers, which deliberately deploy (nonlethally) upwards of 20K volts for multiple seconds.
Sohcahtoa82 4y ago
Yeah, usually when someone parrots the "it is the amps that kill you, not voltage" line, I have to remind them that the amps depends on the volts. A car battery is capable of hundreds of amps, but if you touch the contacts with your hands, you won't feel a thing, because the voltage is too low to overcome your body's resistance. I imagine if you wired the leads to your tongue, your tongue would probably explode though.
- tengwar2 4y ago
  It's advisable to remove rings if there is any way they could short across a car battery. The battery has very low internal resistance, so you can get a sizeable part of a kilo-amp flowing, which due to "P = I^2 R" can generate an impressive amount of heat. In fact some owners of certain Russian motorcycles with a propensity (Ural, Dneipr etc.) were able to weld bits back on in the field by using the carbon contact breaker points to do rough arc welding. Which doesn't contradict you at all - I'm just saying treat car batteries with respect.
elif 4y ago
lmao you couldnt figure out how to turn off your tv... spoilers, hold the power button for 2 seconds.

philistine 4y ago

Also, it's not electronic safety, its straight up electrical safety. There are no electronics in a magnetron.

cuteboy19 4y ago
Even with power electronics we still say electrical safety
- elif 4y ago
  It was a class on embedded electronics and robotics. There are more hazards in electronics than merely electrical hazards. e.g. exploding capacitors, toxic fumes, etc.
kragen 4y ago
A magnetron is a vacuum tube which works by swirling space charge around. Vacuum tubes are "electronics"; the word "electronics" was originally invented to distinguish vacuum tubes (where it matters that the charges are being carried by electrons) from previous electrical devices such as relays, resistors, condensers, motors, generators, and inductors, where you can pretty much ignore the nature of the charge carriers.
robonerd 4y ago
Surely the magnetron itself is an electronic device.

raldi 4y ago

Rather than admonishing everyone for wondering the obvious question, why not just explain your reasoning?

shkkmo 4y ago
High amperages are really only dangerous (in terms of electrocution) with higher voltages. As voltages get low enough, our bodies' resistance means that there won't be enough current passing through you to hurt you. The dryness of the contact point makes a big difference (several orders of magnitude), but even with wet hands, it is pretty much impossible to hurt yourself with < 12 volts. The risks with low voltages and high amperages are from shorts causing rapid heating.
throwaway9870 4y ago
Current flowing through your body is what kills you. But it doesn't flow through you just because it is a high-current supply (think car battery for example). It flows through you because the source voltage divided by your impedance is what controls how much current flows through you. Impedance is the general concept for resistance and basically indicates how current and voltage are related. The higher the impedance, the less current flows. Wearing rubber gloves would increase your impedance from hand to hand significantly. So while high current does kill you, what causes it is high voltage. What is considered high? Depends on your impedance (ex. are your hands sweaty or dry?). When dealing with high-current systems, there are safety procedures and concerns, but they are generally different than high-voltage. The systems I have dealt with are more about burns than electrocution. For example accidentally shorting out a fork lift battery can be spectacular in a bad way.
- iso1631 4y ago
  There's no particular safety concerned when you're playing with hundreds of kilovolts in a typical school. You need it when the thing you're messing with has the capability of delivering a lot of amps.
  - timpattinson 4y ago

deleted 4y ago

[deleted]

xxs 4y ago

I dont know what they did in the uni, I thought it was some wielding or power delivery (CPU and GPUs nowadays deal with 200A+)... So I honestly thought it was high amps, all of them are proper fire hazard. But you are right, likely it was high voltage.

tarsinge 4y ago

Maybe they meant high voltage amps

hedora 4y ago

Once I charged a 1F (not a typo) capacitor with either a AA or 9V battery (can't remember), then touched the leads. Youch!

throwaway9870 4y ago
You must have charged it through some step up device, otherwise the max voltage on the cap is the battery voltage which isn't going to shock you.
- BenjiWiebe 4y ago
  Maybe they pinched the leads together between their fingers. That could be painful.

elif 4y ago

I'm glad you assumed a very limited scope of danger being direct electrocution death because in my class I learned there are many compound forms of electrical accident. To quote NEC textbook: "Even low-voltage installers can still experience unsettling shocks, especially if they are working in an unsafe environment, such as if they are ungrounded or standing on a wet spot,” Johnston said. “While it’s unlikely that such shocks will cause serious injury by themselves, they certainly could literally knock someone off balance, which could be a real safety risk if an installer were standing on a ladder. “In addition, an arc in a low-voltage system has the same potential for igniting explosive materials as one in a 120-plus-volt system. Chapter 5 of the NEC provides rules for installing electrical wiring of any voltage in a hazardous (classified) location, specifically those locations with high concentrations of flammable or combustible liquids, flammable or combustible vapors, conductive and combustible dusts, and so forth.”

elif 4y ago

It's also possible for low voltage shocks to cause your hand muscles to seize the hazard and be unable to release it. In fact, my TENS unit, specifically designed to cause muscle contraction, runs on 9V. Edit: ah... I see a throwaway account was used, so you will never have to confront your mistake. I wish these were banned.

xxs 4y ago
I cant see how 9v dc can shock you aside touching the leads with tongue... or using any step up electronics. As a kid we used to test batteries voltage with the tongue, 9V had a distinctive bite, compared to 4.5V. Even today I can tell the output voltage of a multimeter (in its ohm mode)

elif 4y ago

Lastly, I would encourage you to consider tasers, which deliberately deploy (nonlethally) upwards of 20K volts for multiple seconds.

Sohcahtoa82 4y ago

Yeah, usually when someone parrots the "it is the amps that kill you, not voltage" line, I have to remind them that the amps depends on the volts. A car battery is capable of hundreds of amps, but if you touch the contacts with your hands, you won't feel a thing, because the voltage is too low to overcome your body's resistance. I imagine if you wired the leads to your tongue, your tongue would probably explode though.

tengwar2 4y ago
It's advisable to remove rings if there is any way they could short across a car battery. The battery has very low internal resistance, so you can get a sizeable part of a kilo-amp flowing, which due to "P = I^2 R" can generate an impressive amount of heat. In fact some owners of certain Russian motorcycles with a propensity (Ural, Dneipr etc.) were able to weld bits back on in the field by using the carbon contact breaker points to do rough arc welding. Which doesn't contradict you at all - I'm just saying treat car batteries with respect.

elif 4y ago

lmao you couldnt figure out how to turn off your tv... spoilers, hold the power button for 2 seconds.