Grounding Definition and 131 Threads

Hello, I'd like to discuss what is called "ground loop". Consider the following scenario and call the set "C1 + S + C2" as "the system" -- Ground loop. As far as I can understand, the "noise/hum" at power grid frequency (50-60Hz) is actually due to electromagnetic processes external to "the...

I am facing electric surge problem for last few years at my home. The surge mostly damages electronic gadgets. Both Honeywell and Belkin brand protectors have failed so far. The surge passes through these protectors and blows everything connected to them. Now, I have been told that issue is...

Recently, I purchased a cheap lavalier microphone, the Boya BY-M1, and noticed that the recordings have a constant electric buzzing noise, similar to the sound produced by a Tesla coil. This issue only occurs when my laptop is plugged in, leading me to believe it’s a case of electrical...

I'm reading the capacity chapter of Serway's book, and I had a question about the charging of a parallel plate capacitor. Let's assume the following situation with a modification of the circuit in the figure: we connect the negative terminal of the battery and one of the capacitor plates to...

Hello, My Telegraph Transmitters are in a 100mA loop that is supplied power through a Power Regulator. It appears that my connection to the ground point in the building is correct, but nothing codes out when it goes into ground mode, although I can hear the transmitter coding out correctly...

A single phase, 240V AC supply is used to power the 3 phase motor on my milling machine. A VFD is used to generate the 3 phases required, along with the other benefits such as overload/overvoltage protection, soft start, braking, speed control, reverse, etc. The VFD has an inbuilt EMC filter...

My explantion of this electrostatic induction is that if the disc of electroscope is ground, electrons will flow from the ground and neutralize the disc, leaving the electroscope negatively charged after removal of the ground, but the book says it should be postively charged. As per book, the...

I am having some issues when viewing tracings of my induction heater tank. It has to do with the grounding. First, I will explain the situation; then, I will ask the question. The images show the inverter voltage in yellow which results in a current in light blue. The dark blue is the 90 deg...

Hello, I am a mech engineer teaching myself electrical engineering so please forgive my ignorance. Could someone explain to me how the coil stays open when grounded in the figure 2-12b. With my limited understanding I can see that in 2-13a the if the side of the circuit on the left of the coil...

Hello, If I understand it correctly, the samples are grounded inside a scanning electron microscope (SEM) to avoid charge build up through the electron beam. Also the non-conductive are coated with a conductive layer, so they can be grounded as well. However, I do not know how the charge build...

The story is that I did some wiring additions ` couple of years ago. I extended a Ring Main (cover your eyes dear US readers) and bought one of those socket checkers for a few quid. I have got this far in my life without one but I though why not splash out. The connections, of course, checked...

Non-relevant background So, in the dim time, we had a microwave link installed for our internet service. The dish was on a mast on the second story (about a foot square, no idea what frequency). The installers put in a grounding 1/2 inch diameter rod. I remember because of more than an hour of...

I have purchased a mini whip antenna, made my installment plan however someone has warned me about grounding issue. He said that it makes a lot of difference if the grounding of an antenna is good and advised not to trust to electrical outlet grounding of the house. My question is very...

Click the attached file to see the figure and the book's explanation. The explanation for 27-7 (a) makes sense as the point a comes after the grounding point and before anything else. Therefore it should have a potential of zero. But, to me, 27-7 (b) doesn't make any sense. Why should the...

Hi, I have two similar circuits. One of them is clear for me but I am not sure how the second one works. Let's start with the clear one: a parallel RC circuit, which is explained here: At time t = 0s there are zero volts across the resistor because the capacitor is fully uncharged. After...

Hello, I’ve been working with electricity for a few years and have a misconception that was recently revealed again to me. I remember asking my teacher this question in school and him not being able to answer. In North American homes (and other buildings), the neutral or “grounded conductor”...

So I was reading Jackson's discussion on Image charge method of a grounding sphere. He first assumed an image charge q inside Sphere with radius a, so the potential for real change and image charge is . The by set potential equal to 0 at x=a, he solved q' and y' Then he can get potential...

Summary: Are the tabs on the faceplates for motherboards useful? Typical motherboards come with "plates" that fit over the connectors that are exposed on the outside of the computer case. These plates have tabs that press against metal around the connectors - presumably to furnish a ground...

I am seeking direction, information, resources and thoughts on the following subject. The common interpretation of the National Electrical Code does not allow you to use multiple smaller equipment grounding conductors in place of one larger one (except in a few cases such as a cable assembly...

Let us consider a negatively charged object. We want to neutralize this object, so we touched it by our hands to remove the excess of negative charges by Grounding. Now the question is : Will our body (The Ground) be negatively charged as it gained those negative charges? then why it is called...

Homework Statement 2. Homework Equations 3. The Attempt at a Solution For the first set of questions: I've worked through to part 6), at which is I encountered my first problem. I'm not entirely sure what the question is asking. Is it as if there would be a capacitor between...

These are typical metal roof in my country.. it's connected to iron c-purlins metal screwed to metal sheets. Our structural plans never have any grounding details of this. I'm just wondering what would happen if a live wire touch it or the I-beam connected to it (because we hang electrical wires...

I am currently working on a high power class E amplifier which will sit inside a metal enclosure. It is powered by two power supplies - both are isolated but one of the power supplies is mounted in the same enclosure. The power supply itself is in a metal case and that case is connected to...

Hello, I have read of someone being electrocuted using a generator. I noticed that portable generators don't need to be Earth grounded with a grounding rod. Why not? In the households, all appliances are grounded and directly connected to the ground through the main panel. However, if the...

On a multi-pair cable where each individual pair has its own isolated shield and there is one overall shield around all of the pairs, why do we ground the overall shield at both ends and the individual shields only at the cable origin. I can't find IEEE 518 right now, but i believe it tells you...

When an object with a net charge is connected to the ground by some conducting material the net charge disappears. The only answer I was able to find was that the net charge gets spread out, which will clearly cause it to become negligible. What causes this to happen?

Homework Statement A positively charged rod is brought near the knob of an uncharged electroscope and the leaves of the electroscope diverge. As the positively charged rod is held near the knob, the electroscope is grounded with a wire. Then the grounding wire and the positively charged rod...

I am attending an online lecture course on semiconductor physics. While explaining the common emitter mode of transistors, the professor sketched this diagram on the board: (I added something more to explain better) I understand that the emitter has to be at the same potential, and that is...

I'm currently 20 yrs old. I've always liked physics and was doing A levels in all 3 sciences + maths before I dropped out because of severe mental illness. I'm now at a point in my life where I'm not under obligation to go back to study or work straight away and I have ALLOT of time on my hands...

Hi Got some questions regarding grounding transformers (wye-delta), or maybe I should write, I need someone to tell me if my understanding is correct. First, under no fault operation: Only a small current will flow in the wye side of the grounding transformer, aka magnetizing current...

If a properly insulated man touches with one hand +ve terminal of a 120 V battery and with another hand -ve terminal of (Edit: an another) 120V battery (two batteries are totally isolated, not connected in any way) then will he get electrical shock ? ( I am guessing , not). But if -ve terminals...

Hi, can somebody help me please. I have situation like on picture in link. So, marine electrical system 440V, transformed to 230V for heater. But, my question is, why transformer is grounded on such way. I don't understand this grounding. thank you.

Why is the red (power: pin 2) wire for the servo motor not connected to anything in this circuit? https://github.com/samyk/combobreaker/blob/master/Eagle Files/ComboBreaker_top.pngAlso, on the "bottom" schematic, the ground is connected to the feedback (potentiometer wiper) line...

How would you justify the above question? Please elaborate in detail with diagrams (if applicable). It will be really helpful. Thank you.

Hello The Chinese were kind enough to send me a "music mixer" (XH-M164) and apparently these sell for about 8-11 dollars so I thought I might as well build something cool with it. I found an amplifier aliexpress (http://bit.ly/2nTD8VX) and the recommended transformer for that is a 32v 200VA...

I am working in an industry where my technicians have to short the bus bars on regular basis (manually) for some maintenance purposes. I want to add high neutral grounding resistance to the incoming supply transformer to limit the Line to ground fault. Presently the neutral has been solidly...

Hello, I am trying to solve an issue which occurs when two robots with different static charges make contact. It has been some time since my Physics classes and I have some ideas that are only partly making sense to me. I need to minimize the effect that a static shock is having on a small...

<Moderator's note: Thread split off from https://www.physicsforums.com/threads/what-happens-if-hot-wire-touches-earth-ground.800587/page-4#post-5704259> Why can a phase be grounded without blowing up such as in a star configuration ?No one has answered this sufficiently or simply.

i connected one probe of digital mutimeter to the Earth terminal of domestic ac supply and held the other probe. it showed resistance of 1.8Mohm . but when i touched that end (one i'd held) to the floor. it displays 1( beyond 200Mohm ). why so ? shouldn't resistance be lesser?doesnt any current...

Hi guys, I am trying to find the best way to lay out a grounding system for a typical tube amp. I had in mind to place the filter caps along the HT rail. I can use either axial or radial caps. The issue with the radial caps is they tend to be too big in diameter.I am trying to get to some...

suppose there was no ground stick at power generating station . then there would be no reason for a person to get an electric shock. no need for ground wires. only live and neutral wire for domestic supply. why is the neutral wire connected to Earth at generating station

Would sticking the end of a wire in the ground prong of a outlet ground whe wire and whatever is connected to the other end?

Overview: I've made a grounding mat using a piece of copper speaker wire attached to the grounding prong on a wall plug (I removed the other two prongs). The other end of my copper wire is attached to a sheet of aluminum which I set on the floor like a mat. I checked to make sure that my wall...

Homework Statement What is the current in the 2 ohms resistor? Homework Equations Kirchhoff's loop law The Attempt at a Solution Grounding does not affect how the circuit behaves, so I ignored the ground in and applied the loop law (clockwise from the negative terminal of the 9V battery...

Hello there, I have a question about a raised floor and it needing to be grounded or not. (I posted this question on a different forum but didn't receive an answer ) My only past experience with grounding a floor has been in data centers, where there is 120/208/480v above and below a raised...

So I just got finished with my second physics course (electricity and magnetism) and from what I learned about circuits, to complete a circuit there must be a potential difference to create a current. I just wired up some new off road lights on my vehicle, and when wiring, I ran a wire from the...

Homework Statement So, I always make mistakes on problems such as this (the grounding part), so I'm hoping someone could really explain to me how the process works instead of just answering this particular problem. There are n large parallel plate conductors carrying charges Q1, Q2,... Qn...

Hi! I can't find the method of the solution to this question, it was an exercise on an exam.. There are two grounding electrodes buried in the ground. We make three measurments. First, we measure the first electrode's grounding resistance, which is: 6 ohms. Then, the second's: 7 ohms. Then the...

1 “earthing” for bonding of equipment and circuits to common plant earth electrode potential, 2 “protective earthing (PE)” when this bonding is required for personal safety provisions 3 “grounding” for interference suppressing bonding of screens, sys- tems with ground level 4. low-impedance...

Hi everyone, I wanted ask about the optocoupler circuit used to isolate a microcontroller and a motor driver board.Is it alright if I connect the input and output grounds together to make a common ground and connect it to the ground of the controller. I was of the opinion that an opto coupler...