Conventional vs Electron flow

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electricalengineer3

Joined Feb 6, 2020
172
Therein lies your problem. I have yet to see anyone who uses electron flow use a negative sign when indicating the flow of negative current.
Yeah I think I am starting to see a huge issue in what I wasn't understanding. If we look at current as coming out of the negative terminal that would be negative charge carrier flowing past a point so -coulomb/some amount of time so that is a negative current value. This is the same as a positive current value coming out of the positive side of the battery. I thought that this was not what electron flow was, instead I thought electron flow was defined as positive current leaving the minus side which it shouldn't be, it should be negative right?
 

MrChips

Joined Oct 2, 2009
30,806
Okay so its literally the same convention as what we already have? The thing that is weird is when some people explain electron flow or when you look at military material, they act as if the current coming from the -(electron flow) is positive since it has a negative charge and is going in the opposite direction, so two negatives making a positive
So can we lay this one to rest now that you have finally got it?
 

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electricalengineer3

Joined Feb 6, 2020
172
So can we lay this one to rest now that you have finally got it?
Yes the only thing I am still confused
So can we lay this one to rest now that you have finally got it?
So we define current as the flow of charge. If we look at a point and see - charges going right to left and there’s 1coulomb worth of them going right to left in 1 second we can say there’s one A going right to left. So a negative current going from right to left because of the negative charge so with the right to left arrow -1A. 1. Is this electron flow? If the answer is yes then I get it. The only thing I don’t get is in military books they would still call that right to left current of - charges positive.
 

WBahn

Joined Mar 31, 2012
30,057
Okay so its literally the same convention as what we already have? The thing that is weird is when some people explain electron flow or when you look at military material, they act as if the current coming from the -(electron flow) is positive since it has a negative charge and is going in the opposite direction, so two negatives making a positive
What have I been saying, over and over and over -- in practice, people that claim to be using electron flow do it improperly! So why is it surprising that when they explain it or show it that they do so in a way that doesn't work out correctly when you look at the details?

They show the current going from negative to positive not because the electrons are negatively charged, but because that is the direction that the things that move actually move; that's all they focus on -- they want a positive value of current to mean that the things that move are moving in the direction that they actually move. The underlying inconsistency comes from them using coulombs as a magnitude-only quantity and a staunch refusal to recognize that coulombs is a signed quantity. You will even see them say things like 1 C of electrons, which is fundamentally impossible.
 

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electricalengineer3

Joined Feb 6, 2020
172
What have I been saying, over and over and over -- in practice, people that claim to be using electron flow do it improperly! So why is it surprising that when they explain it or show it that they do so in a way that doesn't work out correctly when you look at the details?

They show the current going from negative to positive not because the electrons are negatively charged, but because that is the direction that the things that move actually move; that's all they focus on -- they want a positive value of current to mean that the things that move are moving in the direction that they actually move. The underlying inconsistency comes from them using coulombs as a magnitude-only quantity and a staunch refusal to recognize that coulombs is a signed quantity. You will even see them say things like 1 C of electrons, which is fundamentally impossible.
Bingo now it all makes sense. So negative charge going in one direction is the same as positive in the other but NOT when you ignore the charge and that’s what some of them tend to do
 

WBahn

Joined Mar 31, 2012
30,057
Yes the only thing I am still confused

So we define current as the flow of charge. If we look at a point and see - charges going right to left and there’s 1coulomb worth of them going right to left in 1 second we can say there’s one A going right to left.
If you have negative charges going right to left, then how can there be a positive charge (e.g., one coulomb worth of them) going right to left? One coulomb is a POSITIVE CHARGE!!!

If you say that there is one ampere going right to left then you are saying that the charge to the left is arithmetically increasing (becoming either less negative or more positive) and the charge to the right is arithmetically decreasing. How can this be the case if you are moving negatively charged things from right to left?

The only way you can claim that a bunch of negative charges moving right to left is one ampere moving right to left is if you invoke a magical mystery minus sign -- which is exactly what technician/military texts do!
 

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electricalengineer3

Joined Feb 6, 2020
172
If you have negative charges going right to left, then how can there be a positive charge (e.g., one coulomb worth of them) going right to left? One coulomb is a POSITIVE CHARGE!!!

If you say that there is one ampere going right to left then you are saying that the charge to the left is arithmetically increasing (becoming either less negative or more positive) and the charge to the right is arithmetically decreasing. How can this be the case if you are moving negatively charged things from right to left?

The only way you can claim that a bunch of negative charges moving right to left is one ampere moving right to left is if you invoke a magical mystery minus sign -- which is exactly what technician/military texts do!
Yes exactly sorry I didn’t explain in words what I was thinking but I’m with you on that. It’s not in anyway correct that’s why I’m wondering why people say it doesn’t matter which you use it seems to matter a lot
 

WBahn

Joined Mar 31, 2012
30,057

Thread Starter

electricalengineer3

Joined Feb 6, 2020
172
Go back and revist the first posts I made in this thread with your new-found perspective, starting with:

https://forum.allaboutcircuits.com/threads/conventional-vs-electron-flow.166883/post-1476600
Go back and revist the first posts I made in this thread with your new-found perspective, starting with:

https://forum.allaboutcircuits.com/threads/conventional-vs-electron-flow.166883/post-1476600
Yeah you were definitely right. I had some other people giving me conflicting information I felt like. If you message me separately I can show you something that you can help me look at
 
I figure by the grace of God and current flow I survived a 45 year career working in electronics. I can honestly say over an entire career and endless formula that never once did it matter which way the electrons flowed.
I took some chemistry class that used electricity. That's where the mix-up started. Then a course in solid state physics. It mattered there too.

Never designed with tubes, but fixed tube stuff. I know sometimes it really matters that yur Voltmeter is 50K ohms/Volt.

It matters a "little bit" when electrons are accelerated in an Scanning Electron Microscope which I maintained.

I set up systems that could measure a few pico-amps. When wires move in the earth's magnetic fields it generates current
My set-up could measure the resistance between 2 spots on a piece of paper and see the effect with humidity.
 
I never learned about "conventional" and "electron" flow in college. EE didn't teach it. They didn't really teach it in chemistry either. They sort of did in the solid state physics course, but never mentioned it by those names or we owe it to Ben Franklin.

I learned about electron orbits and then electron probability.

Nobody speaks the same language: 7/8"=3/4". Same copper elbow. If you go into a refrigeration distributer and buy a 7/8' elbow, it will be a 3/4" plumbing elbow. In some applications, I like a long sweep elbows sometimes.

I thought I knew how to buy machine screws like flat head and pan head. Nope. If your an optician, all screws are measured using overall length.

Everyone has their own conventions. RED is always negative in the thermocouple world.
 

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electricalengineer3

Joined Feb 6, 2020
172
The current through a resistor is V/R where V is the voltage across the resistor and R is its resistance.

If you assume current flow, its direction is from the positive end to the negative end.

If you assume electron flow, it's direction is from the negative end to the positive end.

In either case the value is the same.

Only the assumed direction of the charge carrier flow changes.
Sorry not to start this back up again, this is the only comment I do not now understand, but isn't the value different? The magnitude of the value would be the same but electron flow would have to be negative because it is the flow of negative charge? Unless you are referring to the electron flow that calls the flow of negative charge, positive. My understanding after reading this was that electron flow and conventional were actually more or less the same thing. Conventional is just a positive value going one way and electron flow is the corresponding negative value going the other way. You can flip those back and forth when solving a circuit however you want. Could you message me about this maybe?
 
This https://www.austincc.edu/wkibbe/truth.htm might help and it might make things worse. Don't know.

99% of the time it doesn't matter.

To make an analysis work you assign "stuff goes from + to negative of the battery. Now your conventional current meters work.
In solid state physics, electron beams and electroylsis it might break down depending on what we want to know,
In solid state physics we invent the hole.

In school I dealt with electrolysis and solid state. At work e-beams and solid state.
At work a lot of stuff starts breaking down. Wiggling wires generate electricity. Pushing on insulators generate electricity.
Ican put my resistance probes on paper and make a measurement. Femtoamps are really timy e.g. 1e-14 Amps.
At some point parasitics matter a lot. Insulators blur. You get a different value of impeadance if you use threee 1K resistors in series or 1 3K resistor. They matter if they are soldered on the edge. You might base your answer on what you know rather than what you were told. Your wrong, but your right and so I got credit for my answer and no one else did for my answer.

You also have to watch school. You might learn orbits an then probability. You learn slope and then differentiation.
 

Thread Starter

electricalengineer3

Joined Feb 6, 2020
172
This https://www.austincc.edu/wkibbe/truth.htm might help and it might make things worse. Don't know.

99% of the time it doesn't matter.

To make an analysis work you assign "stuff goes from + to negative of the battery. Now your conventional current meters work.
In solid state physics, electron beams and electroylsis it might break down depending on what we want to know,
In solid state physics we invent the hole.

In school I dealt with electrolysis and solid state. At work e-beams and solid state.
At work a lot of stuff starts breaking down. Wiggling wires generate electricity. Pushing on insulators generate electricity.
Ican put my resistance probes on paper and make a measurement. Femtoamps are really timy e.g. 1e-14 Amps.
At some point parasitics matter a lot. Insulators blur. You get a different value of impeadance if you use threee 1K resistors in series or 1 3K resistor. They matter if they are soldered on the edge. You might base your answer on what you know rather than what you were told. Your wrong, but your right and so I got credit for my answer and no one else did for my answer.

You also have to watch school. You might learn orbits an then probability. You learn slope and then differentiation.
Yes that link helps and agrees with what I am saying. Current is the flow of any charge it can be positive charge flowing one way, or negative charge flowing the other. If it’s in the direction of positive it’s a positive current, if in the direction of negative it’s negative current. My understanding is that you can use both of these in circuit analysis at once because the negative version is just conventional current in the opposite direction if you want to think about it that way. It seems the only time you have to be careful is when one defines the flow of electrons or negative charge to have a positive value, then that must be treated differently
 

nsaspook

Joined Aug 27, 2009
13,272
The bottom line is this:

Ben didn't make an actual mistake and conventional current is not wrong or backwards. In his two types of electric fluid model he was "backwards" (Sign conventions aren't "wrong") about way metals conduct a charge flow.

Electron current is a subset of conventional current where conventional current is describing all possible charges and their movements.
 

Thread Starter

electricalengineer3

Joined Feb 6, 2020
172
The bottom line is this:

Ben didn't make an actual mistake and conventional current is not wrong or backwards. In his two types of electric fluid model he was "backwards" (Sign conventions aren't "wrong") about way metals conduct a charge flow.

Electron current is a subset of conventional current where conventional current is describing all possible charges and their movements.
Correct, so you can use electron flow and positive conventional current in the same circuit analysis since electron flow is really just negative conventional current. Most people seem to refer to conventional current to just mean positive current, but I get what you’re saying.

what you cannot do is use the version of electron flow that defines the flow of negative charge as positive in concurrence with conventional current, because they require different sign conventions that cannot be adhered to simultaneously. This is the type that really complicates things. People who want to model thedirection of flow of negative charge should do so with a negative current value.
Conventional current does not always flow against electrons. If the current value is negative that IS the direction negatives would/are movinf
 

WBahn

Joined Mar 31, 2012
30,057
what you cannot do is use the version of electron flow that defines the flow of negative charge as positive in concurrence with conventional current, because they require different sign conventions that cannot be adhered to simultaneously. This is the type that really complicates things. People who want to model thedirection of flow of negative charge should do so with a negative current value.
Isn't that what I've been saying since, oh, https://forum.allaboutcircuits.com/threads/conventional-vs-electron-flow.166883/post-1476600

You are not going to change the fact that people who want to use "electron flow" are almost all going to do it improperly. The best you can do is recognize this and make the necessary corrections/translations yourself when interacting with them.
 

Thread Starter

electricalengineer3

Joined Feb 6, 2020
172
Isn't that what I've been saying since, oh, https://forum.allaboutcircuits.com/threads/conventional-vs-electron-flow.166883/post-1476600

You are not going to change the fact that people who want to use "electron flow" are almost all going to do it improperly. The best you can do is recognize this and make the necessary corrections/translations yourself when interacting with them.
Yeah, you’re right, I read back through the thread and your comments were great. I just saw that other comment that made me think well technically if you are using electron flow correctly and giving it a -value then you can use it solving circuits problems just fine alongside conventional current. Just wanted to confirm that point
 
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