Capacitors/capacitor banks-What are they used for?

[Dr Prepper]

I never seen the question answered so forgive me if it has been, but capacitors store potential, also known as volts. Unlike a battery they don't store current too. They're usually used in circuits to resist a change in voltage by loading and unloading as there are spikes and dips in the voltage. Combine it with a coil of wire in the circuit which resists a change in current by building and collapsing a magnetic field and you have a great filter for electrical circuits. At least that's what I remember from my apprenticeship twenty years ago, LOL. I work with big ones on a regular basis and know for certain that a capacitor can be quite dangerous if it's not shorted out. That is how they ship so that there isn't a static charge. Capacitors (condensers) from a car or motorcycle distributor can be quite fun for people to shock other people as mentioned. Bigger ones can kill you and are not a toy so be careful!

Um the Farads is literally a measure of its storage capacity. The volts is a running voltage. Capacitors do absolutely hold capacity not just voltage. Thats why they use them to stiffen current draws in systems that try and draw too much amps for the basic system like car stereo's and bass notes. The system can't draw enough amps fast enough for the system so they add a capacitor to provide instant CURRENT (not volts) when needed then rapidly recharges when there isn't a deficit.

They can also be used in RLC (Resistor /inductor(coil)/capacitor) circuits such as radios and micro waves/radar systems. And provide a tremendous amount if voltage by basically making +voltages on one side of the time graph and -voltages on the other side. The net difference can easily be 1k volts and these circuits can be in stuff like pocket radios etc that have a very low battery voltage but they are obviously stepped up as you can see. There are several ways to do this.
Its best not to mess with electronics (even seemingly safe ones) unless you know what your doing.

And small capacitors can easily kill you as well doesn't need to be big at all. The voltage is the killer. Without looking IIRC it only takes what 35-45 Milli amps to stop your heart. But skin starts conducting around 45-60 depending on the moisture content and 120-200 volts will easily conduct through the skin.. So thats really not a lot at all a capacitor the size if your finger with the correct ratings will be enough to kill someone if they are unlucky enough to grab each terminal with each hand.

A short is a short.. If its shorted out it can't store energy right? It's a safety device so you know it's not charged when out of the system. Because they are so dangerous.
A capacitor is QUITE dangerous when being shorted out when still charged. You should drain it, check it, then apply the short to keep it drained so you KNOW its safe to handle.

A *short applied to the charged cap is literally how they do those shrunken quarters and those coils blow up like a grenade!

 

[monks]

Um the Farads is literally a measure of its storage capacity. The volts is a running voltage. Capacitors do absolutely hold capacity not just voltage. Thats why they use them to stiffen current draws in systems that try and draw too much amps for the basic system like car stereo's and bass notes. The system can't draw enough amps fast enough for the system so they add a capacitor to provide instant CURRENT (not volts) when needed then rapidly recharges when there isn't a deficit.

They can also be used in RLC (Resistor /inductor(coil)/capacitor) circuits such as radios and micro waves/radar systems. And provide a tremendous amount if voltage by basically making +voltages on one side of the time graph and -voltages on the other side. The net difference can easily be 1k volts and these circuits can be in stuff like pocket radios etc that have a very low battery voltage but they are obviously stepped up as you can see. There are several ways to do this.
Its best not to mess with electronics (even seemingly safe ones) unless you know what your doing.

And small capacitors can easily kill you as well doesn't need to be big at all. The voltage is the killer. Without looking IIRC it only takes what 35-45 Milli amps to stop your heart. But skin starts conducting around 45-60 depending on the moisture content and 120-200 volts will easily conduct through the skin.. So thats really not a lot at all a capacitor the size if your finger with the correct ratings will be enough to kill someone if they are unlucky enough to grab each terminal with each hand.

A short is a short.. If its shorted out it can't store energy right? It's a safety device so you know it's not charged when out of the system. Because they are so dangerous.
A capacitor is QUITE dangerous when being shorted out when still charged. You should drain it, check it, then apply the short to keep it drained so you KNOW its safe to handle.

A shirt applied to the charged cap is literally how they do those shrunken quarters and those coils blow up like a grenade!

NERD

 

[Dr Prepper]

Guilty as "charged"
I was just coming back to say I'm not trying to flame on ya either. Electronics are kinda hard to grasp and easy to forget. Its been a few years for me too.

 

[Flopsweat]

Um the Farads is literally a measure of its storage capacity. The volts is a running voltage. Capacitors do absolutely hold capacity not just voltage. Thats why they use them to stiffen current draws in systems that try and draw too much amps for the basic system like car stereo's and bass notes. The system can't draw enough amps fast enough for the system so they add a capacitor to provide instant CURRENT (not volts) when needed then rapidly recharges when there isn't a deficit.

They can also be used in RLC (Resistor /inductor(coil)/capacitor) circuits such as radios and micro waves/radar systems. And provide a tremendous amount if voltage by basically making +voltages on one side of the time graph and -voltages on the other side. The net difference can easily be 1k volts and these circuits can be in stuff like pocket radios etc that have a very low battery voltage but they are obviously stepped up as you can see. There are several ways to do this.
Its best not to mess with electronics (even seemingly safe ones) unless you know what your doing.

And small capacitors can easily kill you as well doesn't need to be big at all. The voltage is the killer. Without looking IIRC it only takes what 35-45 Milli amps to stop your heart. But skin starts conducting around 45-60 depending on the moisture content and 120-200 volts will easily conduct through the skin.. So thats really not a lot at all a capacitor the size if your finger with the correct ratings will be enough to kill someone if they are unlucky enough to grab each terminal with each hand.

A short is a short.. If its shorted out it can't store energy right? It's a safety device so you know it's not charged when out of the system. Because they are so dangerous.
A capacitor is QUITE dangerous when being shorted out when still charged. You should drain it, check it, then apply the short to keep it drained so you KNOW its safe to handle.

A shirt applied to the charged cap is literally how they do those shrunken quarters and those coils blow up like a grenade!

The defense is wrong!

"No, there's mowa!"

 

[Dr Prepper]

Not gunna lie. Thats the clip I was originally looking for (you know it!)
But they didn't have it *at giphy.com (surprisingly) and I gave up. Lol. So thanks.

 

[Flopsweat]

Not gunna lie. Thats the clip I was originally looking for (you know it!)
But they didn't have it giphy.com (surprisingly) and I gave up. Lol. So thanks.

I couldn't forget that clip. Marisa Tomei at her best.

 

[monks]

Guilty as "charged"
I was just coming back to say I'm not trying to flame on ya either. Electronics are kinda hard to grasp and easy to forget. Its been a few years for me too.

LOL, I'm just playing too. Your definitely in a class above me in the electrical knowledge department! I never got that deep into it in my apprenticeship. I don't rebuild or troubleshoot electronic components but I do change a lot of parts. I got as far as semi conductors, GTO's, IGBT's in my apprenticeship before I took an early setup and that was it. What I don't know I guess at but I'm pretty proficient troubleshooting inverter systems and power generation. My son is an electrical/computer engineer student in his final year at OSU. He thinks I'm an idiot when it comes to electricity but he can't fix anything (yet) either!

 

[Yarome]

The voltage amp is the killer. Without looking IIRC it only takes what 35-45 Milli amps to stop your heart.

FIFY

The rest is fundamentally accurate though.

The voltage is what "pushes" the amps (current). Think of it like water through a garden hose carrying rice along with it. You can have a slow trickle or a tremendous amount of water pressure moving rapidly through a hose, and the concentration of rice may be very low... or... extremely high in either combination of slow or fast moving water.

Too much rice can really ruin your day.

 

[monks]

I couldn't forget that clip. Marisa Tomei at her best.

That film is a classic!

 

[Dr Prepper]

FIFY

The rest is fundamentally accurate though.

The voltage is what "pushes" the amps (current). Think of it like water through a garden hose carrying rice along with it. You can have a slow trickle or a tremendous amount of water pressure moving rapidly through a hose, and the concentration of rice may be very low... or... extremely high in either combination of slow or fast moving water.

Too much rice can really ruin your day.

Yeah but without the voltage, the amps don't matter. That's why low voltage is safe. No one has ever really worried too much about killing yourself working on your car even though its high amps.. You are correct the amps are what kills you period. But its volts that deliver that dose.
The two are very closely related. But yeah a taser won't kill you. But neither will high amps with low volts.

But also AC travels deep through the circulatory systems and in veins like where your heart is. DC runs on the surface of your skin and can cause massive burns.

I found this online trying to make sure I remembered this correctly as like @monks its been a "few" years..
This explains it better. The main point is the human body (or anything really) is a resistor. So the standard voltage division formula V over I × R applies.
Which would be voltage divided by resistance = current (I)
But still much like treating every gun as its loaded you just treat every circuit like it will kill you and use the one hand rule (insert joke here) and don't wear metallic jewelry etc and you'll be good ever if you lose your one hand it still want kill you (plus you'll have a backup)

From stackexchange:

Assuming the "1000 V & 1A" and "1 V and & 1000A" refers to the voltage and current that normally occurs in some electrical circuit, the 1000 V (at up to 1 A) is far more dangerous than the 1 V (at up to 1000 A) because the higher voltage can force more current through the human body.

Ohm's Law says resistance = voltage / current, so to push enough current through the body to harm you at 1V the resistance has to be very low - much lower than normal skin resistance. 1V applied directly to the heart might be enough, but that is unlikely to occur by accident.

AC is more dangerous than DC because the peak voltage is higher (which causes higher peak current that breaks down skin resistance more) and it reverses polarity regularly giving the effect of multiple shocks. The heart is particularly sensitive to mains frequency AC because it will try to follow the frequency and go into fibrillation.

Other parts of the body can handle a lot more current, but will be cooked or burned by high current (I still have a hole in my thumb where 240 VAC went through my hand 40 years ago). RF frequency AC doesn't have the same 'shocking' effect, but causes burns that are slow to heal.

Another danger of electric shock is uncontrolled muscle spasms. AC gives continuous shocks that may prevent the victim from letting go, whereas DC only shocks at the moment of contact. Muscle spasms can tear ligaments and tendons, and might cause a dangerous accident such as falling off a ladder or violently hitting something.

However "1 V & 1000 A" DC could still be dangerous if you shorted it out with a metallic object (ring, screwdriver etc.) that vaporized due to the high current flow and splattered molten metal over you. That is why we use insulated tools and wear eye protection even when working on extra low voltage high current circuits.

 

[Dr Prepper]

Plus the other reason I said voltage kills is the current it takes to stop your heart is almost virtually nothing. Its basically 100% chances that if theres voltage high enough to conduct through the skin there will certainly be at least 35-45mA so its a given the amps will be there. The voltage is really the major variable here. 33-45mA or whatever is enough to only power a LED or two. Its nothing.

Anyway. Science class is closed.

 

[Flopsweat]

FIFY

The rest is fundamentally accurate though.

The voltage is what "pushes" the amps (current). Think of it like water through a garden hose carrying rice along with it. You can have a slow trickle or a tremendous amount of water pressure moving rapidly through a hose, and the concentration of rice may be very low... or... extremely high in either combination of slow or fast moving water.

Too much rice can really ruin your day.

You're actually both right.

Current is important when the context is cooking tissue.

When the context is interrupting the heartbeat, and possibly stopping it, very low current can do that if the voltage is high enough and applied properly. In order to be reliable, more current is preferred. This is why defibrillators can deliver quite the wallop and even burn tissue if they are turned up high enough.

 

[Dr Prepper]

and even burn tissue if they are turned up high enough.

..On your shiny metal azz!!..

 

[Yarome]

I guess I say amps, because, lacking sufficient current (amps), even extreme voltage is survivable, while the rerverse is not true. Sufficiently high amperage is what causes the muscles to contract, tissue to burrn and can kill, relatively regardless of the voltage, but yes, it also depends on how (AC vs. DC) and at what rate (voltage) the current is delivered to the human body.

I was speaking in the loosest of terms without an in depth analysis that most 2A forum members probably aren't too interested in.

Just wanna make things blow up!

 

[Dr Prepper]

I guess I say amps, because, lacking sufficient current (amps), even extreme voltage is survivable, while the rerverse is not true. Sufficiently high amperage is what causes the muscles to contract, tissue to burrn and can kill, relatively regardless of the voltage, but yes, it also depends on how (AC vs. DC) and at what rate (voltage) the current is delivered to the human body.

I was speaking in the loosest of terms without an in depth analysis that most 2A forum members probably aren't too interested in.

Just wanna make things blow up!

Hence why I think I mentioned taser's which this is their principal function.. it only accidentally stops hearts! (And pace makers!!!)
(I can't tell if this is Santa clause or a albino Mr. T... I'm going with Mr. T.)

 

[Yarome]

it only accidentally stops hearts! (And pace makers!!!)

...and they can't light a cancer stick worth crap!!