Potentiometers in Analog Inputs

[billbo911]

Originally Posted by EricVanWyk

Sure, I used these to remember:
V = C R (even if it blinks 12:00 forever)
P = V C
V(olts) C(urrent) R(esistance) P(ower)

To do your calculation, I took:
Power = Voltage^2 / resistance

Originally Posted by AustinSchuh

While you may have done this to simplify things for non EEs, I find your choice of symbols for current very unique. Most, if not all, EEs use the symbol "I" for current. I thought you were talking about capacitance there for a moment.

Wait, there's more!!

Being a EE, I too found the symbols a little odd, but I understand their usage for the purpose of remembering easily.

In fact, the way I remember is:

P=IE ====> Power=Current *Voltage
That's right, "I" is for current AND "E" is for Voltage.

In actuality, "E" is for "Electro Motive Force".
Honestly, I don't quite remember exactly why "I" is used for current. Maybe one of our other EE's can fill us in?



(Forgetting is what happens when you don't use what you know. Or, maybe it is what happens when you get old. Darn, I forget )

[brVex]

So, if the potentiometer is of 5W I do not have problems?

What about the analog input value range?

Sorry for my english!

Gustavo

[Tom Line]

And to break it down into words:

Voltage (in volts) = Current (in amps) * Resistance (in ohms)
Power (in watts) = Voltage (in volts) * Current (in amps)

This is for a DC system. AC is similar, but you need to be careful what voltage you use.