Electrical Circuit Basics Part 1 - Line & Load

Bryan teaches the Kalos techs the difference between line and load in part 1 of his electrical circuit basics series. This video will help lay the foundation for understanding diagrams and schematics by showing how electrical circuits are organized.

You need to have two points before electrons can move; electrons move from one side to another based on the potential difference in charge (voltage) between the two points. That's why we use two meter leads to read voltage.

If we were to have +/-120 volts on L1 and +/-120 volts on L2, we'd have a 240v circuit between those two legs. On a battery, that circuit would be between the positive and negative sides of the battery. When working on a system, it is counterproductive to focus on each individual point; you have to keep the entire circuit in mind.

We can connect one side of a battery to a switch, and the other side of that switch could connect to a lightbulb, and the other side of that lightbulb could connect to the other side of the battery to make a basic electrical circuit. The line side of a switch refers to the wire that goes into the switch (from the battery or power source), and the load side of a switch refers to the wire between the switch and the load (the component that does something; in this case, the load is a lightbulb).

In some cases, you may have multiple switches; if any switch is open, then the light can't light up. However, each switch has a line and load side. The line side is always on the side of the power source, and the load side is always nearer to the load.

[deanfoster]

I was so involved in this short video I was bummed when it ended. Waiting for part two.

[JuanMartinez-vrbg]

I watched this like 10 times to fully understand it, thanks

[troydobson]

Thank you for the way you explain everything when you teach. Awesome material.

[abrahamgreenidge]

Sir this was most clear to me, great help you’ve shared lots of light 💡

[dickyrock]

Ya just came across this by accident. Really hope there are a lot more videos. Many thanks.

[RealMangaAddict]

Very well explained, this helped a lot. Thank you

[Honestandtruth]

Thank you for Clearify .... and for Sharing...👍👍

[Mike-yhtv]

Thanks...need these type of videos. Electrical circuits is one of my weakness. Keep those videos coming thanks

[kidalwys]

Very nice it’s like the beginning of school all over again lol

[tranhoa]

If switch at after the light bulb, which side is line any which side is load?

[knighthvac]

Great video, I got my 10 years son a snap circuit jr by elenco, he is interested in what I do and loves it that board, wish I could give them to my guys lol

[pelmqku]

i am korean
I found out by chance
I am not good at English
I think it's a really exciting lecture.

[aircooledtx]

Source/switch is the way I was taught. Back before Noah.

[sridharchitta]

In the analysis of circuits that make use of resistors, diodes and transistors, it is
necessary to determine the operating point (voltage and current) of the device connected
in a network, which is made from devices whose parameters are known.
It is often necessary to determine voltages between terminals of a network with no current flowing.
Consider for example the network which consists of two resistors R1 (terminals marked A and B) and R2 (terminals marked C and D). Their ends (A and D) are connected to the positive and negative terminals respectively of a power supply of 12 V dc. The other ends of the resistors are left unconnected.

Suppose that the resistors R1 and R2 are 10 ohms each.
What will a voltmeter read if it is connected between terminals A and B?
What will be the reading of a voltmeter connected between the terminals C and D ?
What will be the reading of a voltmeter connected between the terminals B and C ?

Electrostatics and circuits belong to one science not two. To learn the operation of circuits, Current and the conduction process, resistors, capacitors and inductors and how discussing these topics with a unified approach makes it easier to understand how there is a voltage of a single wire connected to one terminal of a battery watch these two videos

The last frame References in video #1  lists two textbook 4 includes topics that discuss simple networks and the physical processes which causes the appearance of potential drops.
Specifically, in Chapter 3 discussions of load line graphs and yheir use in fixing the operating points of devices duch as resistors, diodes and transistors is discussed.
We continue for now with a brief discussion of the cause of the voltages between the dofferent terminals of the network example in this post.

When the network is made, electrons will enter the battery positive terminal and the potential of the resistor R1 would have been raised. The battery positive terminal, would drop in potential due to the neutralising action of the few electrons, but then its chemical
action will quickly restore its potential difference (p.d.) to 12 volts. The migration of electrons will stop, when the potential of the resistor equals the battery positive potential.
And all this happens within a few picoseconds. There will be a few surface charges on the resistor R1, and these indicate its new status of potential.
It should be clear that a voltmeter when connected between terminals A and B of circuit will read ‘0’ volts, because the potential of the resistor R1 and the battery positive, will be the same, namely, 12 volts. In the case of the resistor R2 connected to circuit zero, a few electrons would have entered the wire and the resistor R2 from the negative terminal of the power supply which is circuit zero, making the potential of the resistor R2 the same as circuit zero. There will be a few surface charges on the resistor R2 that indicates
its new status of potential. A voltmeter when connected between terminals C and D of circuit will read ‘0’ volts, because the potential of the resistor R2 and the battery negative will be the same, namely ‘0’ volts.
The current in the circuit will be zero because of the open circuit.
Since the potential of terminal B is the same as that of A, its potential is 12 volts.
Since the potential of terminal C is that of the battery negative or circuit zero (terminal D), it is ‘0’ volts. Therefore, a voltmeter connected between the terminals B and C will read
the same p.d. as that between the terminals A and D namely, 12 volts. We can allow a current to flow in the circuit by simply connecting a wire between
terminals B and C thus, short-circuiting them.

The current in that case will be 12 V/(10 Ω +10 Ω) = 12 V/20 Ω = 0.6 amps.

The two points marked on the x- (voltage) and y- (current) axes are joined together, and this line is called the “Load line” of the network. The load line is the locus of points, or pairs of voltage and current values for the voltage between terminals B and C and the current in the circuit, when the terminals B and C are bridged by a resistance. The load line is fixed for a fixed power supply voltage and fixed values of resistors R1 and R2.

[adfggffffffddffd]

what about the other side of the light that is connected to the negative side of the battery? Is that a line side or load side?

[sohelshaikh]

So the component that shows the output is called as load

[SeanLeonDrumz]

The second side of a switch should actually be labeled a switch leg. Second side of a load would be the load side. At lease thats how NEC would define it.

[brunomelvin]

Please make vedio on relay holding circuit in HVAC please.

[MrSuprcharg]

Don't Electrons flow from negative to positive?

[MrLukecastillo]

i was searching for what is a line to line load