The basics of electrics - AKA Electricity for Dummies

[DebianDog]

What the heck is a volt, amp, watt, ohm, mah, C, etc...

Well here it is... all laid out for us thicker headed folks. Plus, it is kind of a fun read.

[Jermo]

The description of Volts isn't exactly accurate but it's good enough for non-Electronics types. The way it's written follows the analogy of water in a pipe.
Jermo

[celter]

The Volt would be the height difference between the water level in the tank and the end of the hose. A bigger tank would not increase the pressure (Volt)

[Fox222]

Originally Posted by Jermo

The description of Volts isn't exactly accurate but it's good enough for non-Electronics types. The way it's written follows the analogy of water in a pipe.
Jermo

That is exactly how they teach it to 1st year electronics students. Or at least when I was in school a long, long time ago.
They don’t need atomic structure, just how it reacts.

[Jermo]

I went through 2 years of electronics in High School, another 2 years in the Navy, then another 2 years for my associates. I've never heard that presentation.

Maybe it was given in the electrical class?

[Fox222]

Originally Posted by Jermo

I went through 2 years of electronics in High School, another 2 years in the Navy, then another 2 years for my associates. I've never heard that presentation.

Maybe it was given in the electrical class?

The water analogy has been used for years in electronics. But that doesn't necessarily mean they teach it that way everywhere.
When I was in high school I took an electronics class and the water analogy was the first thing we covered. Then when I went to tech. (also elactronics) I got it again the first day.

[6sic6]

For those who feel really bright:

http://amasci.com/ele-edu.html

Some outstanding reads in there.

[DominicD]

Hmmmmmmmmmmmmmmmmmmmm Dog hmmmmmmmmmmmmmm. The analog is fine but there are alittle bit of misunderstanding or misleading sentences, but it's fine for our purposes. One thing that is really wrong is your discription of a watts "...Watt is a unit of work done over time". Work over time is Energy and has units of joules (Integrals !!! Hurray for calculus). BTW If the water in the hose is suppose to be the electrons then technically the water should be flowing from the ground back through the hose and into the tank.

[jance445]

What is the mechanical (using the water analogy) equivalent of a switching regulator vs a linear?

[DominicD]

A linear series regulator - A globe value that would let you control the volume of water (no this is not technically accurate but it works for the comparison to the others)

A linear shunt regulator - A little valve that drains the water from the main pipe so you can control the flow in the main pipe

A switching regulator - A ball valve that you open and close fast. The longer you leave it on compared to when its closed the more average water will flow.


While the flow of water is the analogy is current and regulator uses voltage just think of the current being converted to voltage by a resistor or something.

[alex_p_kiel]

Volts in the electromotive force in a current or how fast it is moving. Amps is the electric potential or ammount of power. Watts is is volts x amps. Ohms is electrical resistance. From my own calculations, a "C" is about 2 or 2.1 amps. A miliamp is one-thousandth (0.001) of an amp. I don't know if I am forgetting anything.

[DominicD]

Originally Posted by alex_p_kiel

Amps is the electric potential or ammount of power. Watts is is volts x amps.

Amperes ARN'T the amount of power. Power is volts x amps.

[alex_p_kiel]

Yes, amps is the amount of power, watts is a measurement of both amps and volts, the term watts is just a more general term.

[DominicD]

Originally Posted by alex_p_kiel

Yes, amps is the amount of power, watts is a measurement of both amps and volts, the term watts is just a more general term.

Sorry this is incorrect. Amperes is the measure of the number of coulombs per second through a surface. Power is the measure of energy over time or volts x amps.

[Pinecone]

Amps is a measure of the the flow of electrons. How many flow ina given period of time. That is not power.

Volts is how hard the electrons are pushed through the circuit.

Power is the product of volts and amps.

Watts are not a measurement of volts and amps, it is measurement of the power. 10 amps at 1 volt is the same watts as 1 amps at 10 volts.

And 746 watts is 1 horse power. Again POWER.

[supergenius]

What does the C stand for on ly-po pacs? Also, the S?

[wecoyote]

Originally Posted by supergenius

What does the C stand for on ly-po pacs? Also, the S?

C = Capacity
S = Series
P = Parallel

[supergenius]

Originally Posted by wecoyote

C = Capacity
S = Series
P = Parallel

...how do I know which one to buy? If I go up from a 10C 3S 2200mah to a 20C 3S 2200, will my speed-control have a heart attack? SC is a 30A Walkera. If I need to upgrade, what should I get?

[DominicD]

The C rating only determines how much maximum current your battery can supply. You motor determines how much current is drawn. Your esc doesn't care the least bit. If you motor doesn't need more then 10C your new 20C pack won't make any difference. If you motor was trying to draw more then 10C with your old pack your new pack will be able to provide the current your motor demands. As an example lets use a 3S 2100mah pack on a 35A esc.

35A / 2100mah = 16.7C max

which means going from a 20C to a 25C lipo is a big waste of money.

[spork]

Originally Posted by HFG

One thing that is really wrong is your discription of a watts "...Watt is a unit of work done over time". Work over time is Energy and has units of joules (Integrals !!! Hurray for calculus).

HFG,

I'm guessing there's a semantics issue here, because...

Watts is a measure of power, which is work (or energy) per time interval. Energy or work are measured in joules, and a watt is a joule per second.

Energy and work are synonymous (you say "work over time is energy").

As I said, I may just be misunderstanding you, because I suspect you know all this.

EDIT:

Looking back at this I think I see the problem. Is it possible you're confusing "work" and "power"? Work = Energy. Power = work/time (or energy/time same thing).