Understanding Current

Different strokes:
India Essen Welding
& Cutting 2012
Electricity
To explain electricity with a simple
example. Think of electricity as
water flowing through a pipe or
garden hose. The water is really
electrons in the metal that makes up
the wire. The hose is the wire that
transports electricity. Basically,
electricity is created by magnets
spinning inside a whole bunch of
wires. The magnets spinning around
cause electrons to move which
creates electricity.
The three most basic units in
electricity are voltage (V), current (I)
and resistance (r). Voltage is
measured in volts, current is
measured in amps and resistance is
measured in ohms.
Once again using transport of water
to explain the above phenomenon,
the voltage is equivalent to the
water pressure, current is equivalent
to the flow rate and resistance is like
the pipe size.
There is a basic equation in electrical
engineering that states how the
three terms relate. It says that the
current is equal to the voltage
divided by resistance. Further,
kVA = Volts x A
kW = Volts x Amps x Power Factor
or [kVA x Power Factor]
Looking at different electrical
equipment, you will notice that the

power ratings are either expressed 

in kVA or sometimes in kW . To 

understand the difference between 

kw and kva - KW is called actual or 

real power, or simply the amount of 

power that is available to do real 

work. On the other hand kVA is 

known as “apparent” power.