Electrical Grounding Explained | Basic Concepts
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⌚Timestamps:
00:00 - Intro
00:49 - Why do we a Ground?
01:23 - Earth Ground
02:07 - Graphical Symbol
02:32 - Common Ground
02:58 - 1) Typical example - electronic schematic
04:17 - 2) Typical example - Industrial schematic drawings
04:35 - Ground loops
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In this video, we’re going to discuss the commonly used, but often misunderstood term, Ground.
There are lots of different names for Ground…
There’s Earth, Earth Ground, Neutral, Common Ground, Analog Ground, Digital Ground, and Instrument Ground… just to name a few. And then you have terms like Ground Loops…
Quite often, Ground means different things to different people. For example, Ground to an electrician might mean something different than Ground to electronic engineers.
There are lots of reasons for grounding.
Proper grounding is a critical safety measure in all electrical systems and installations.
We ground the exposed part of electrical equipment so that internal wiring failures don’t raise the voltage potential of these exposed parts to dangerous levels.
Let’s look at some of the different perceptions of the ground.
It’s probably safe to say that Earth and Earth Ground are the same things.
Earth ground is the reference point in an electrical circuit that is a direct and physical connection to the earth. Earth Ground is the ground that you walk on.
Earth Ground is true zero volts. It is the true zero reference for any and every electricity discussion.
You don’t have to go far to see evidence of earth ground.
You might be able to spot a copper rod in the ground with a heavy wire attached to it.
This Earth Ground wire runs to your power panel and ultimately connects to all the Ground terminals of every receptacle in your house.
Notice that we’ve used an electrical symbol for Earth Ground.
The symbols used to indicate ground terminals are found in the International Electrotechnical Commission document IEC 60417 Graphical Symbols for Use on Equipment.
Symbol 5017 is the symbol for Earth Ground.
Every electrical circuit needs to be complete for the current to flow. In many applications, the common ground becomes the return path. For example, your car chassis is a common ground for the return current to the battery’s negative terminal.
Sometimes you’ll see the Earth Ground symbol used incorrectly on electronic schematics. The intention is to symbolize a Common Ground and it may not be connected to Earth Ground.
If ground points are not connected to Earth Ground but are connected to a Common Ground, it would be more appropriate to use the symbol IEC 60417 5020. This symbol suggests the points are connected to a frame or chassis terminal.
This brings up an interesting question…
Are all the components at the common ground potential connected at one point on the frame or chassis, or are they connected to the chassis at multiple locations?
Unfortunately, the schematic does not provide that answer. The schematic does not provide any clue as to physical connections. Industrial schematic drawings will indicate ground points and often provide more detail but physical connection points are still a mystery.
This brings us to a term called Ground Loops.
A Ground Loop is an unwanted electrical current path that can cause havoc in equipment or process control systems by introducing unwanted electrical noise.
These undesired Ground Loops are created when two supposedly connected points are not at the same electrical potential. That’s when Ohm’s Law takes over and creates an electrical current flow between two points.
Ground loops can be avoided if all devices are grounded together at one point. This type of grounded is referred to as Star Point grounding.
Unfortunately, in large industrial plants, multiple-point grounding is the reality, and the possibility of ground loops is high.
With so many connections referenced to the ground within a facility, the chances of needing more than one ground point are great.
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I graduated in Electrotechnics and Electronics but they neaver teached this so clear during my school years. Thanks a lot for this useful information. I had ground loops problems in the metal box of a desktop computer that messed up the powersupply. Now I know what to do to solve it.
That's amazing to hear! Thanks for your positive feedback. If you have any questions along the way, feel free to reach out!
You are putting lot of work in making these easy to understand animations. Excellent job and thanks alot for sharing.
Glad you like them!
I have been searching a video like this for my life. TONS OF THANKS.
Glad I could help, Sonny!
Thump up for Electrical ground explanation, also I said TONS THANKS.
Thank you so much for this high quality content. Your responses to almost each and every comment speaks volumes. Subbed.
Thank you very much for your kind comment, we truly appreciate that!
Keep em coming, RealPars! Thanks for all your good content.
Thanks a lot, Bob!
Superb presentation. Even people like me can understand about various grounding and importance of it.
Thank you, John!
Thanks i had 1 query, this video gave me solution! 👍🏽🙏🏼
Glad to hear that! Happy learning
Excellent video. Thanks for your enlightment!!
You're very welcome!
¡¡¡Guauu!!! Excelente video.
Gracias por compartirlo.
De nada, Luis!
I was also asking myself what those people mean by saying "grounding". Now it is clear for me. Thank you very much!
Glad to hear that, Elmir! Happy learning
@@realpars please elaborate on chasis grounding pls asap
@@haabhhh4290 Chassis ground will connect different metallic parts to a single point generally the enclosure and to earth. This will allow to redirect the electricity and avoid people to get shocked by touching enclosure if a wire is touching it.
This is why in elettronic is better use "0V reference A/D", in the schematic you can highlight the connection with the chassis and the ground (if necessary), but also the connection between 0V-digital and 0V-analog.
If the target of your circuit are boats, cars or airplanes "ground" means the chassis of the veicle.
Yeah, but in that case is the negative, right? That's the reason you have to disconnect the negative before when removing the battery.
this channel is INCREDIBLE!
Thanks a million for your kind support!
That is a great explanation, thank you so much!
Glad you enjoyed it!
Awesome video! Keep doing this stuff
Thanks a lot, Pedro!
Exelente explicación. Me preguntó por qué no lo explican de esta forma cuando estudiaba la universidad. He visto muchos videos y con este me quedo claro lo que hace el PID.
Gracias, Marcos!
As soon as you mentioned that the ground symbol was the most misused I thought to myself “guilty!”
I’ve worked more with low voltage digital/analog circuits (mostly for classes at school, a little at work now) and we just use whatever symbol we like to denote a 0V point, without regard to whether it physically means chassis, Earth, or just a copper trace. At school this didn’t matter because every circuit we worked with was just a little bunch of wires and a battery, with no metal chassis or Earth connection to be confused with.
We almost exclusively used the most common “Earth Ground” symbol, but some professors would use “Common Ground” or “Chassis Ground” in their schematics.
Finally a near-complete discussion of ‘ground’. Excellent.
Thank you, Bernard!
This. is. very. important. and. great. lesson. so. i. appreciate. your. this. video. lesson. so. Thank. you. very. much
You're very welcome!
Very good informative video, thanks.
Glad it was helpful!
You should also note why it's important to declare what "standard" you use for the basis of your discussion. Still people around who think the NEC is a standard when it's not and it specifically states that. Also the symbology changes between standards i.e. IEC, IEEE, NFPA and JIC. JIC I believe is outdated, but if you declare that's what you're using, then you have to go by that standard. Love the video. Good explanations!
Hi Albert. You are correct. The NEC is not actually a true "Standard". As per their own definition " Adopted in all 50 states, NFPA 70, National Electrical Code (NEC) is the benchmark for safe electrical design, installation, and inspection to protect people and property from electrical hazards.". In fact certain parts of the NFPA 70 can be rejected due to regional restrictions. Thanks for your input.
Excellent! Clear and concise!
Glad it was helpful!
Thank you for the great info!
Our pleasure, Shaun!
Howdy. Great.
I usually say soil electrode and soil currents to discern from the fuzzy and blurry use of grounding and earthing.
Regards.
Thank you for sharing this helpful video. The only quibble I have with it is calling “planet Earth” the true 0 volt reference. More generally, voltage is the integral of the electric field between two points in space, and one of the points is 0 volts by definition (I.e., 0 volts does not necessarily refer to the planet Earth). Your video is, nonetheless, very helpful.
Hey hubercats, thanks for your point of view.!
Its arbitrary, you can set whatever reference potential wherever you want and get valid results as long as you are consistent with the notation. The easiest way is to set reference potential to 0V (for ease of calculations) and to set it to planet earth. All in all, when safety is concerned, you most often stand on the ground, therefore you are also 0V and whatever potential you touch, that'd be the voltage to shock you :D If you have 1000V point, then it is 1000V. Would be much harder to do it when earth would be set as reference of 2342,1214V. Then it'd take w while to calculate voltage ;)
@@sumilidero 🤣
Great video, been waiting for this one!!
Hope you enjoyed it!
Thanks for the video, I was looking for such explanation so long. Please upload another video explaining the remaining ground types
Thanks a million, Subu! We appreciate such great support.
Damn excellent video explanation. Some Ground concepts I've never even quite heard of like the Analog and Digital Ground as well.
Thanks a million, Ardent!
Thanks you! You really give imformative video thank you very match... God bless
Amazing! Glad to hear that, Richmond!
Informative ❤️
Glad it was helpful!
Great illustrations.
Thank you!
Great explanation.
Glad you think so, Will!
Thanks a lot for this excellent explanation
Every man and his dog has a different take and definition on this. Frankly I don't think most people understand wtf is going on.
Electricity is basically just modern magic as far as I'm concerned
awesome video I really appreciate this
Glad it was helpful!
Thanks👍🏼
Thank sir.👍
Excellent video. Being a mechanical, why "electrical noise" create havoc?
Thanks for your excellent work.
Electrical noise is often induced into or interferes with normal operational or control signals. If these control signals are altered in any way, false readings can occur resulting in incorrect responses.
@@realpars Thanks for your kind reply. Keep us educating.
Thanks.
I have an old physics textbook that describes the earth as a limitless energy sink that electrons can be poured into without it ever filling up .
Thats why its wise to start our electrical coordinate system and place 0V there :D Although, you could set earth to whatever potential you want and still get valid results as long as you keep that notation along the way.
Thank you very much!
You're very welcome!
Informative!
Thank you very much!
Sir, thank you very much for nice explanation. Sir, can you explain in details the earthing procedures of ac, dc earthing of pv solar system and components. Also ac & dc earthing of transformer and transmerless inverters.
Hi Mahmood,
Thanks for your comment and your suggestion. I will pass this on to our course developers!
Thanks for sharing and happy learning!
Thanks for sharing
You're very welcome!
Thanks for your sharing
You're very welcome!
Great work
Thank you!
Video editing is awesome
Thank you!
Excellent knowledge
Great to hear that!
Great job
Thank you, Saleh!
Really nice.
Thank you!
excellent video
Glad you liked it!
Ultimately, earth and ground really boil down to what its used for, as 0 volts reference point, and/or wire for all "extra" current to flow to/trough, especially in case of fault.
Please make video on LV generator neutral grounding and it effects , advantages and disadvantages
Thanks for your topic suggestion! I will happily go ahead and pass this on to our course developers.
These techniques implemented in building (in1996) avionics test rig, at ADA B'lore.by (we) ex_HAL technicians under Sri V. Subbarao
All symbols (some I don't come across) are at one place to learn more. Thanks
Great!
Thank you!
Love this channel
Great to hear that, Johan!
Hi sir. What a great vedio, with simple explanations easy to understand.
By the by I would like to know sir, what is that the grounding problems arises in Active Magnetic Bearings systems. Thanks you inadvance.
Hi Prasad,
Thanks for your kind comment, glad to hear that the video course was helpful!
The grounding problems that arise in active magnetic bearing systems would be a very interesting topic for a future video course. I will go ahead and forward this as a topic suggestion to our course developers!
Thanks for sharing and happy learning!
Clear as mud !!!!!
Thank you, Ron! Great to hear that.
Excellent video from RealPars, as usual. However a longer video would have allowed to go a bit more in details.
Thanks for your comment and feedback! We appreciate that
VERY VERY NICE VIDEO SIR
You're very welcome!
Excellent
Thank you so much!
Good sir
mayb u guys should make a group of videos on electrical fundamentals
Thanks for the suggestion, James!
Great job ! Please can u make a video about TT ; TN and IT shematics ?
Hi Ahmed!
Thanks for your comment and your suggestion. I will pass this on to our course developers!
Thanks for sharing and happy learning!
Thank you
You're welcome!
Ultimately you have to know the standard that was used for the design of the facility, then understand changes made afterwards may or may not have adhered to those standard, then you have to understand the symbols as defined on those drawings because other symbols are legitimate if they are listed on the drawings. Drawings are a higher order of precedence than standards.
Thank you for adding that!
Lol the hardest part for me to understand was ground dis this explained it in under 3 minutes, thanks
Sir, I am again submitting request. Sir, can you explain in details the earthing procedures of ac, dc earthing of pv solar system and components. Also ac & dc earthing of transformer and transmerless inverters.
Hi Mahmood,
Thanks for your comment and your suggestion. I will pass this on to our course developers!
Thanks for sharing and happy learning!
Very good
Thank you very much!
When using a two prong tester to find the hot line, we can old one prong between our thumb and finger. Inserting the other prong in the hot socket, the bulb will light.
Our body is absorbing electrons. Does that mean "ground" means electron hungry?
Are our bodies behaving like capacitors? If we held that prong all day with the other on the hot side of a plug, would we reach capacity?
Hi Roger. Thanks for reaching out. I'm not sure what you mean by our body being electron absorbers. We certainly have several electrons in our body and if we contact a voltage source or a source of EMF, these electrons will begin to move if they have an "Escape route". And that is not a good thing. We can be killed with less than 50 mA of current flow. We aren't like a capacitor and our bodies won't "charge" like a capacitor. As a side point, we can't charge capacitors with an AC supply. A capacitor is charged as you describe with a DC source.
@@realpars : I guess what mystifies me is the fact I'm wearing rubber soles shoes and feet off the ground in my house on wooden floors, and just holding one leg of the idiot light current is moving in and out. How does that work if I'm not, at least temporarily, absorbing electrons?
perfect video
Thank you, James!
@@realpars i studied Electronics and electrical wiring and some of this ground symbols are misunderstood at times 🤦
Excellent video. Can anyone tell please than when comes the role of ELCB (earth leakage circuit breaker)?
Thanks.
The device measures current differential on the 2 lines (L & N in europe). If the amount of returning current is smaller than the incoming current, that means there is a current leaking and this is dangerous (fire, electrocution..) So it breaks the circuit, until you manually turn the switch up again. Usually they are 300mA, for humid rooms like bathrooms they must be 30mA
@@alexvdz8840 Thanks for your kind reply. Keep it up...
Good video bro
Glad you liked it!
5:00 I'm not sure the ground loop solution depicted is necessarily a solution. E.g. if the current from block #2 (left to right - 1, 2, 3) is much greater than the current at block #1 then circuit #2 is going to effect circuit #1 -or- #1 is much less than #2. I believe this is why these grounds are advised to be spaced apart far enough.
Hi Lou. Thanks for your input. The circuit #2 (right-hand) depiction could be drawn differently. I think the audio description would be clearer if the return from each block went directly to a single connection point, such as a bolt connected to the chassis of a vehicle. Unfortunately, the current depiction could be interpreted as the return from Block 1 connects to the return of Block 2, then the 2 returns are connected at a common ground point.
A lot of respect and love from India🇮🇳🇮🇳🇮🇳
Thank you very much!
Now I understand the differences between.
Glad to hear that!
As we all know that circuit needs to be closed path to flow current. When live wire touches body of equipment and that equipment is grounded, how it makes closed path? Because live wire is coming generation station or near by transformer so current follows all the way to generation station to make close path?
Hi there. Thanks for your question. Ultimately, all supposedly grounded equipment is grounded to the same electrical point. This point is not usually the same physical point, but it is the same electrical point therefore a closed circuit is formed. I hope that answers your question.
Thanks
You're very welcome!
I’m still confused. How is a car frame a viable option as a ground? What about the cars chassis or frame allows it to be a ground? It’s not a copper rod in the ground it’s just a huge metal body. The reason I ask is because I’m trying to create a home audio system out of car speakers. The box is meant to be somewhat portable but I have no way of grounding it to the earth and still being portable. Is a metal plate the solution/is it a viable ground point?
Hi @Asap Mimic. Here's where the term "ground" becomes confusing. In your situation, "ground" is the negative terminal of whatever you are using for a 12-volt DC power supply. In the car, the "ground" is the negative terminal of the battery, which is the same as the frame of the car. In order to operate the same car system at home, you'll need a 12-volt DC power supply. The negative terminal of that 12-volt power supply will be the "ground". you do not need to connect to any earth ground.
At 2:00 you show a main electrical panel or first means of disconnect. The ground and neutral bus bars look to be separated. They must be connected or just have one. The neutral, equipment ground and earth ground are bonded there. The current flows in a closed loop which includes the transformer and no current on the ground wires under normal operation. In case of a ground fault the current on the ground wires will still go to the neutral on the transformer because it's bonded to the neutral in the main panel and the breaker will trip if the current more than the rating of the breaker. It doesn't flow to earth ground as the impedance is too high. The primary purpose of earth ground and the ground rod is to shunt outside static such as lightning strikes to it's source, the earth, and not your home electrical system.
Hello @Ted Sanders. Thanks for reaching out to us. You are absolutely correct. The neutral and ground are to be connected together for sure. We don't have a physical wire connecting the 2 bars together but. They are connected via the ferrous metal enclosure, which I believe is acceptable.
@@realpars I don't believe that is acceptable. You need a more purposeful connection, not an incidental one. The most common way and only in a main panel, not sub panel, is to use the green screw supplied. It bonds the ground, neutral bus bars and the case.
Subscribed
i would so much a video on how to check and correct easily ground loops. Such a shame on my site
Hey!
Thanks for your comment and your suggestion. I will pass this on to our course developers!
Thanks for sharing and happy learning!
Hi Sir
I have a confusion
Transformer neutral is grounded so when we using neutral on load side, there is a current flows in neutral..my question is if there is current flowing in neutral then why transformer C.B is not tripping by earth fault?
Hi Muhammad. I'm not sure I understand your question. The neutral wire current is normal while the ground wire provides a path for abnormal electrical current to earth. A GFI CB detects earth current as it is faulty. It will not detect neutral current because it is normal.
Really great information
Glad it was helpful! Thank you for sharing
Hi, I saw that grounding body îs quite necessary especially for people with cronic disease as I am. I live at 4 th floor, so I have to use grounding of electricity socket. But I want to add 2 fuse in series on the grounding cable for safety reason. Any idea about what type of fuse ( what curent, voltage) . Thanks
Hi there. You've asked an interesting question for sure. The jury is out on the effectiveness of fuses in series. Some will tell you that a second fuse serves no purpose and others say that it does. I'm not sure how you are planning to double fuse as you'd have to do some serious cable splicing in order to insert your fuses in series. Quite likely, your circuit breaker provides all the protection you need??? But, not really knowing what you are trying to protect, it's difficult to provide an answer.
@@realpars the fuses could be put în a plastic tube according to fuses and cable dimensions. Whole cable and fuses must tested preferably in laboratory. If anyone was in my place when a lightning strike(I saw that strike) street electric transformer ( and distroyed it) and then the lightning went out 10 centimeters from electric socket situated at 2 meters from me, you will serious think to put at least 2 fuses ! And other protection measures.
@@realpars As You know at high voltage it appears flashover phenomenon - I saw it with my eyes in a factory at electric test and I see the lightning came out from socket ar home. In this case it îs advisable to prolong insulation ....adapt things.
i got a question mr if i got one big workshop with machines of 50iA 100iA and 250iA (including plcs for each one) how do i know how many electrical ground holes i need??
Hello @axelateon. Thank you for your question. I don't know what machines you are referring to. It's always best to consult your local electric authority to inquire about grounding requirements as they often vary from one authority to the next.
what is TT &TNS system of earthing explain with diagram
why TT system alone is not enough
In TT the earth is provided only locally. The earth connection on a socket leads to physical earth and nowhere else. The problem is that impedance of the earth may be too high to trip the breaker in case of a fault. However, nowadays, that can be fixed with the use of RCDs.
In TN system the earth is provided by the electric system, There are three variations: TN-S, TN-C and TN-C-S. In TN-S the house gets a separate earth and neutral and these are not connected inside the house. Eventually they will lead to the same place. Where they are connected is the business of the electric company, Ideally at the transformer. In TN-C the house gets a common neutral and earth i.e. a PEN-wire and the same wire goes all the way to the sockets where is is separated. This is obsolete and such systems are no longer installed. In TN-C-S. The house again gets a common neutral and earth but they are separated at the main panel and kept separate. This prevents the raise of voltage in the earth cable and therefore stray currents that can generate interference.
In TN in many counties a local earth electrode is also required to reduce risk in case of a PEN-fault. In the UK that is not required.
Note that in apartment buildings where different entities are responsible for wiring inside and outside the apartment things can get more complicated. MY apartment gets separate earth and neutral but they are combined as the installation inside the apartment is much older.
❤❤❤
Interesting
Happy learning!
Can you be electrocuted by touching the ground, though? I was being taught how to use an outlet tester and the instructor said we insert one end into the socket and hold the other end in our hand, and that way our body acts as a ground. I did not understand how I did not get electrocuted.
Hello @Rustin Stardust. Thanks for your feedback. I'm not sure what tester you are referring to. I'm curious about holding one end of the tester in your hand. Is this tester similar to a multimeter? Without more detail about your tester I can only assume it has an extremely high resistance and therefore would draw negligible current when connected to any ground, or your body connected to ground. I'd be happy to reply to any additional feedback.
Could a voltage source with a lower voltage be used instead of grounding? Doesn't grounding waste electricity to some degree?
It seems like the answer would be "YES", but the scenario you describe is not feasible. A power supply does not provide voltage through 1 wire alone. There needs to be a load and a wire connected back to the common side of the power supply. The voltage is actually a voltage difference (between + and COM) that drives the device. The device only consumes the amount of power required, and this results in a voltage drop across the device. If there is no load (voltage drop), then you have a short-circuit. Current flows from (+) to COM, or for physicists, positive holes flow from (-) to (+). Grounding is a separate issue. Grounding is provided as safety for short circuits that may electrify housings or cabinets. Grounding does not waste electricity because, under normal circumstances, there is no flow of current to the ground. In this video, we learned it is common to represent 0V (or COM) with a ground symbol, which is not typically earth ground but rather the (-) of the power supply. Using the ground symbol allows us to simplify the electrical diagram, as shown at 3:25 in the video.
@@realpars In SWER electrical power distribution, the EARTH is used as the "return wire" and yes the resistance of the ground path does waste some energy. If the "ground path" has the same or lower resistance vs a wire than it makes no difference, example: the car's metal frame.
Why use the "Chasis Ground" instead of "Analog Ground" in the Op Amp example you gave? 🤔
Hiya Mau365PP. Yup, my point exactly. Why is that ground symbol used in this opamp schematic? Who decided to use that symbol, and where exactly is it connected? Is it connected to chassis? Analog ground? Hard to tell from the schematic itself.
Next: TN-S installations
Ground is needed for project
I have just 1 question suddenly
Is it possible for 2 different "earth grounds" to have different voltages?
Hi Skyler, Well, you’ve opened a can of worms with that question. 😊 The electrical potential of Earth is not always the same everywhere. If you have a voltmeter with very long leads connected between 2 rods driven into the ground at locations quite far apart, you may actually see a potential difference. That could cause a current flow between these 2 rods if a circuit was completed. That’s why it’s best to connect all supposedly grounded devices to one reference point, or one Earth grounded rod, if that is your reference point.
@@realpars
Thank you very much
Why most electronics reference using earth ground symbol? BTW nice vid
Hi Abdullah. That's a very good question. There really isn't a good answer. Convenience? Familiarity? What all viewers should know though is that just because the earth ground symbol is used does not mean that the common or ground points(s) are actually connected to earth.
Lol these explanations are better than my bachelor
That's an amazing compliment, Michael! Thanks for sharing!
Conventional DC current in the video? Thank you
Hi Ted. Hmmm.....we didn't talk about any DC conventions in our video as we were mainly focused on AC grounding circuits. What exactly did you have in mind? as you know, conventional current flow is based on the notion that current flows from positive to negative. That notion was debunked earlier in the last century when it was discovered that current flow is actually negative to positive. No bother really, as current is still current and bites if you touch it.
I once tried to repair a guitar and when I plugged it into an amplifier, I heard a loud chirping noise instead of a hum. Turned out it's because of a ground loop created by the laptop power supply... The noise disappeared after I plugged the amplifier into a different socket.
Thank you for adding that!
i thought electrons travel from a negative point to a positive. the battery through chemical reaction deposits the electrons ( ions) on the negative plate. current only flows when we have a conductor to complete the path, but here he shows electrons traveling thru the battery to the positive plate then moving thru the circuit. this is just the opposite way i was taught. now i am really confused.
Hi Jody. You are absolutely correct. Electron movement or "current flow" is from negative to positive. Many of us old-school types still use what is called "Conventional Current Flow" notation which seems to show current flow from positive to negative. Although not actually correct, Conventional current flow notation is still widely used in many educational and training institutions around the world.
For those who knew nothing about electricity before watching this video, then the phrase quote
" electrical noise" should have been explained. I still don't know what it means & will have to look it up before watching anymore videos to learn about electricity in our homes, in our bodies and on planet earth.
Hi Cynthia. Thanks for your comment. As you mention, you can find loads and loads of info on the term “electrical noise” on the internet. As it wasn’t a main theme or focus of the video, we didn’t go into great detail. In short, electrical noise is any “unwanted” induced signal or voltage that interferes with or can cause problems with the electrical circuit. electrical noise is created by lots of pesky things that happen inadvertently such as radio frequency interference.