4VIDEO - UNDERSTANDING VOLTAGE, AMPERAGE & MORE

In this video I'm going to tell you all about volts, amps, AC and DC current, and

other terms you need to know. Voltage is to electricity what water pressure is to

hydraulics. It's the force behind the electrons, the force that wants to drive

them through electrical resistance. One of the first decisions you'll have to

make is what voltage you'll design your system around. The lowest is 12 volts and

the highest you're likely to see is about 48 volts. There are pros and cons

to the different voltage choices and I'll get into lots more detail about

that later. Amperage or amps for short is to electronics what flow rate is to

hydraulics. One amp of current flow is fairly small in a renewable power system

and you might see amperages as high as 100 amps on the primary side of a large

system. It's quite common to see 20 to 50 amp current draws happening. AC and DC

are terms that you'll find part of most renewable power systems. AC stands for

alternating current. 120 volts AC is what comes out of most North American power

outlets and the term alternating refers to the rhythmic changing of polarity of

a given current flow. Here in North America that happens 60 times a second

DC refers to direct current and it's the kind of electricity that comes out of a

battery. The positive pole stays positive and the negative stays negative. Another

concept you need to understand is power and in the world of electricity this is

expressed in watts. Power is the ability to do work and the higher the wattage

you're dealing with the more work that circuit that electrical flow can

accomplish for you. Calculating watts is pretty simple. You take the voltage

multiply it by the amperage and the number you get is watts. This is the

electrical equivalent of the horsepower rating of your car engine but what if

you wanted to know something about the quantity of electricity? For that you'd

need to multiply wattage by the amount of time, the hours that that wattage was

being exerted. So we have watt hours. Since the numbers here get pretty large

it's more commonly referred to as kilowatt hours. Kilowatt meaning a thousand watts. To put this into perspective if you're lucky enough to

live in an area with low grid energy prices you might pay five cents a

kilowatt hour. At the high end in places like where I live we can pay 20 cents a

kilowatt hour. When it comes to designing your system power will first come into

play when you decide the size of inverter you need to provide the kind of

power required for your home situation. Power figures will also come into play

as you economize so you use energy as wisely as possible so you don't need to

build a system that's overly large. Kilowatt hours will be very useful to

you as you decide how much quantity of electricity you need to store in the

batteries of your system. This will relate to your energy consumption and

how much you're producing with wind and solar. Just to recap voltage is the

pressure in a circuit sort of like how tightly is the clamp squeezed down and

how eager there are the electrons to get out. Amps refer to the flow rate in the

circuit. For any given voltage you can have a small flow rate a small thin

garden hose squirting water or you can have a large fire hose gushing water. The

pressure in the two hoses is the same but the flow rate is very different

Watts refers to the power in the circuit so you can have a small lightning bolt

or a big lightning bolt depending on the wattage involved. And kilowatt hours

tells us about the quantity of stored electricity. You can have a small

container of power in storage or a large container