## Why Battery rated in Ah (Ampere hour) and not in VA.

Why Battery rating in Ah (Ampere hour) and not in VA.
Battery stores charge in the form of chemical energy and then converts it into electrical energy to utilize for a specific time. The amount of available charge is the capacity of a cell or battery which may be expressed in Ah (Ampere-hour). Moreover, in a charged battery, the numbers of molecules are limited to create a flow of electron in electric circuits, so, there must be a limited number of electrons in a cell/battery which they motivate through a circuit to fully discharge. Now we have the option to rate the battery capacity in Number of flowing electrons for a specific time, but, it would be a headache, because there are a vast number of electrons in it.  So we have another option (1C (Coulomb) = 6.25 x 1018 electrons, or 6,250,000,000,000,000,000 electrons.
In addition, 1A (Ampere) = 1 coulomb of electrons per second and,
1h = 3600 Seconds
Therefore;
1Ah = (1A) x (3600s) = (C/s) x (3600s) = 3600 C.
A (1 Ampere) = 1 Coulomb per second = C/s
But,
Why make up a new unit for battery capacity rating when an old one unit is doing just fine? L
Of course! To make your lives as technicians and students more difficult.  ;)
As they do for electricity units… i.e. 1 Unit of Electricity = 1kWh = 1 board of Trade Unit...

## 10+ Design & Simulation Tools for Electrical/Electronics Engineers Online

10+ Electrical & Electronics Engineering design, analyzing and simulation free Online Tools
Hi folks!
As you know that we have already shared an article about Android apps for Electrical and Electronics Engineers, Students and Technician. We have also shared online electrical and electronics calculators for free to use. Today we will share online design, schematic and simulation tools list for Electrical and Electronics engineers and students. I hope you will like it because these tools don’t need to download and install in your computer because it is on web-based tools. In addition, these all tools and apps are free to use and you can design, analyze and simulate any kind of circuit, module and project with multiple parameters. If you find this post useful, the Please! Share with your friends. Thanks

Below is the list of free online Electrical & Electronics circuit simulation tools.

DoCircuits
Click images to enlarge
 Light Detector circuit with DC restoration

DoCircuits is an interesting as well as learning circuit design and simulation tool.

## Electrical Wire & Cable Size Calculator (Copper & Aluminum)

Wire & Cable Size Calculator (Copper & Aluminum)
Today, we are here with another comprehensive Copper and aluminum wire size calculator
As we have discussed in detail the topic of “How to calculate the proper wire size for Electrical Wiring. Now you can take the advantage of this calculator to do this job J
Calculating Wire/Cable Size formula for single Phase Circuits
Wire Circular mils =2 x ρ x I x L / (%Allowable Voltage drop of source voltage)
Calculating Wire/Cable Size formula for Three Phase Circuits
Wire Circular mils =√3 x 2 x ρ x I x L / (%Allowable Voltage drop of source voltage)
Where;
ρ = Specific resistance or resistivity of Conductor
D = Distance in Feet (One way) i.e. ½ the total circuit length
Note: the Value of ρ = Specific resistance or resistivity of Conductor is used here for copper and aluminum is 11.2 and 17.4 respectively at 53° C (127° F)
• Also check the “Good to know” Section after the calculator
Enter value, And click on calculate. Result will show the required quantity.

You must knowInput ValuesResult
Source Voltage (V): 110 120208
220 230240
277 440480
Number of Phases: Single-PhaseThree-Phase
Current in Amp (A):
One Way Distance (feet):
Allowable (VD) 3% of VS5% of VS
 Wire Size Copper Aluminum
Good to Know:
If the wire size is greater than all gauges (i.e 0000 is largest one size of wire in), then electrical engineer measure it in CM, kCM or MCM instead of inches, because inch is a small unit of these kinds of  wires. Where;
A circular mil (CM) is a unit of circular area with a diameter of one mil (one thousandth of an inch). It corresponds to 5.067×10-4 mm².
Where:
1000 CM (circular mils) = 1 MCM or 1 kcmil = 0.5067 mm², so 2 kcmil.
It is a unit for referring to the area of a wire with a circular cross section.

## Wire & Cable Size Calculator in AWG

Wire & Cable Size Calculator in AWG
As we have already discussed that how to select the proper wire size for Electrical wiring installation in  detail under the topic of How to determine the suitable size ofcable for Electrical Wiring Installation with Solved Examples (in both British and Si System). Now we are here to present the Wire and cable size calculator for you.
Calculating Wire/Cable Size formula for single Phase Circuits
Wire Circular mils =2 x ρ x I x L / (%Allowable Voltage drop of source voltage)
Calculating Wire/Cable Size formula for Three Phase Circuits
Wire Circular mils =√3 x 2 x ρ x I x L / (%Allowable Voltage drop of source voltage)
Where;
ρ = Specific resistance or resistivity of Conductor
D = Distance in Feet (One way) i.e. ½ the total circuit length
Note: the Value of ρ = Specific resistance or resistivity of Conductor is used here for copper and aluminum is 12.9 and 21.2 respectively at 75°C (167°F).
• Also check the “Good to know” Section after the calculator
Enter value, And click on calculate. Result will show the required quantity.
 Enter values: Single Phase Three Phase Copper Aluminium 120 Volts 208 Volts 220 Volts 230 Volts 240 Volts 277 Volts 440 Volts 480 Volts
 Distance in feet, one way: Total Circuit Amperes (A):
Result
 Minimum wire size:
Good to Know:
If the wire size is greater than all gauges (i.e 0000 is largest one size of wire in), then electrical engineer measure it in CM, kCM or MCM instead of inches, because inch is a small unit of these kinds of  wires. Where;
A circular mil (CM) is a unit of circular area with a diameter of one mil (one thousandth of an inch). It corresponds to 5.067×10-4 mm².
Where:
1000 CM (circular mils) = 1 MCM or 1 kcmil = 0.5067 mm², so 2 kcmil.
It is a unit for referring to the area of a wire with a circular cross section.

## IC 555 Timer Calculator with formulas & Equations

IC 555 Timer Calculator with formulas & Equations

Formulas and Equations for This calculator

Frequency (f) = 1/ [ ln(2) x C x (R1 + 2R2) ]

Frequency (f) = 1.44 / C x (R1 + 2R2) …. Where… 1/  ln(2) = 1.44

TP = ln(2) x C x (R1 x R2)

TP = 0.693 x C x (R1 x R2) …. Where… ln(2) = 0.693

TN = ln(2) x C x R2)
TN = 0.693 x R2 x C …. Where… ln(2) = 0.693

Where;
C = Value of Capacitor in Farads
R1 and 2R2 = Value of the Input Resistance
f = Frequency in kHZ
TP = Positive or High Time from each pulse
TN = Negative or Low Time from each pulse

Enter values and click on calculate. Result will display the calculated quantities.
Enter values:

 Resistance R1: kΩ Resistance R2 kΩ Capacitance (C): µfarads
Result
 Positive Time Interval TP: ms (millisecond) Negative Time Interval TN: ms (millisecond) Frequency ( f ): kHz (kilo Hertz)

## Battery Capacity Calculator

Battery Capacity Rating Calculator
Formula and Equations for Battery Capacity Calculator
Battery Capacity in mAh= (Battery life in hours x Load Current in Amp) / 0.7
Battery Capacity= (Hours x Amp) / Run Time %
Where;
Battery Capacity = in mAH (milli Ampere hours)
Battery life = in Hours
Load Current = Consumption of device in Amperes
0.7 = Battery Cycle life considerations (Run Time)

Note: In ideal case, the battery capacity formula would be;
Battery Capacity = Battery Life in Hours x Battery Amp
Also Check Battery Life Calculator

Enter value, And click on calculate. Result will show the required quantity.
Enter values:

 Battery Life : Hours Load Current (Consumption of Device): mA
Result
 Battery Capacity Rating: mAh ( Milli-Ampere Hours)