Questions tagged [earth]
The earth tag has no usage guidance.
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Why on earth are o-scopes earth referenced?
Thinking about it: You would never find a "Grounded" multimeter as robust and useful if a path to ground through the multimeter were introduced, modifying the circuit's behaviour and possibly damaging ...
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Why is main's neutral tied to earth?
My dad is an Electrician and I myself am an Electronics Design Engineer, and to this day he still hasn't been able to give me a good reason for this.
Consider the two following pictures/situations - ...
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Why don't we use neutral wire for to ground devices and earth wire for closing the circuit?
I know that the neutral point of a distribution transformer is connected to the grounding (earthing) wire, so I think they are the same.
Can I use the neutral wire for protecting metal-cased electric ...
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"Ground" vs. "Earth" vs. common vs. negative terminal
This may just be me not having a degree in electrical engineering or electronics, but the whole notion of "ground" and "earth", when used in electrical circuit diagrams (especially integrated circuits)...
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Why is earth used for ground? Literally earth?
I never considered earth to be particularly conductive. It's just dirt, after all.
However, I've seen "earth ground" conductive stakes driven into the ground in order for electricity to be grounded, ...
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Static shocks all over the building
I just came from the local library, it’s quite big, and most of it is made of an architectural design using mostly painted metal book shelves painted with some kind of anticorrosive paint along with ...
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What is the right way to float a home lab?
I just got myself some new toys for my lab at home like 30V DC power supply, KKmoon signal generator and a Rigol DS1052E. I want to float everything, because I don't want to spend any money on stuff ...
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Is ground connection in home electrical system really necessary?
I know that the answer to my question is "Yes, it is!". The ground connection is needed to avoid a person touching a metallic part of faulty equipment to be electrically shocked. So the ...
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How to stop plastic granules sticking to the iron wall of their silo?
In our factory, we have some large (8 meters tall and 3 meters in diameters) iron silos for storing the plastic compounding material. Every time the silos are getting unloaded from the granules, the ...
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Ground Symbol, which one I should use?
I normally use this symbol in my schematic as my signal ground.
But recently my manager asked me to use this symbol instead because the one that I am using is the earth ground and I should use the ...
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Why is chassis connected to earth ground but not neutral?
My question arose from my previous questions. Here depicts how electricity is distributed to houses:http://www.epanorama.net/documents/groundloop/feed_1phase.gif It seems like the earth ground and ...
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How many "grounds" are there and what is the difference?
I stumbled upon many terms for ground, naturally as newbie I got very confused.
ground earth
chassis ground
earth ground
common ground
signal ground
Are there any more?
I assume some are for AC and ...
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Are countries that use 2-pin plugs less safe than countries that use 3-pin plugs given that the earth is missing?
Will there be occasions when using 2-pin plugs is safer than 3-pin plugs? Is it accurate to say that 3-pin plugs are always safer given the presence of earth?
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Why is earth pin absent in phone chargers plugs but present in laptop ac plugs?
Both mobile phones and laptop get dc voltage from ac source for charging.These chargers have transformer for isolation and rectifier + filter if i am not wrong.I guess the amount of output dc and ...
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USB peripheral: connecting USB shield to GND?
I have read through many recommendations articles, and many StackExchange questions, but haven't come up with any clear understanding as there are many conflicting information out there. The simple ...
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Is the link between the earth/chasis terminal and the utility transformer established through a dedicated wire or the soil?
I was following a tutorial on power supply transformers and at the very beginning I have encountered the following illustration:
I added the names TG and HG for the LV transformer ground and the ...
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Dangers of floating oscilloscope
Conversation between Bob Pease and Paul Rako taken from this video, where Rako talks about modifying an oscilloscope such that it is not connected to earth:
Pease: "Have you ever tried hanging a ...
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Should RVs electrical system be grounded to chassis?
I have an RV with both 12V and 230V systems. The 12V uses internal battery, while 230V is supplied from outside via plug. Should I connect these systems to metal frame of vehicle (minus of 12V or ...
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When do I need a protective earth?
My company is developing a new handheld power tool. We are a rather inexperienced team and I am not a electrical engineer but I am concerned about the safety of our customers. We are located in ...
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Why the neutral of the UPS or inverter or generator is advised to be earthed/grounded?
In my company we had few earthing related issues. When an consultant was brought in and apart from solving the issue, a suggestion was made to ground the neutral of the UPS and diesel generators that ...
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Does potential difference exist between Earth ground in geographically diverse locations?
Earth ground is used as a reference from which all voltages are measured in systems which are earth grounded. Because the earth absorbs or dissipates nearly unlimited electric charge, it should always ...
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The path of electrons in AC circuit?
I have a question regarding the AC circuit shown below. If we ignore the voltage drop caused by the long cable, I think the device will work and the circuit can be considered as a closed circuit.
Now ...
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Addressing poor Earth resistance on hill top
I work in a radio station situated on a hill top. The Earth resistance measured at this location is quite high, measuring around 9 Ω. There is no deep gorge nearby to make a fresh Earth Pit. How can I ...
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Safest way to ground a metal enclosure
I am currently building a nixie clock with some high frequency components (GPS) and I am planning on putting the clock in a metal enclosure. The highest voltage used in the clock is approximately ...
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The chance of a lightning strike - reduced or increased?
If I connect the receiver and TV body to the earth, does it reduce or increase the chance of lightning strikes the dish antenna?
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Resistor or low impedance path between common ground point and mains earth?
A simple EPA (ESD Protected Area) consists of 3 things:
wrist strap
antistatic mat
common point ground
Wrist strap and antistatic mat both should grounded to the common point ground.
ANSI/ESD S6.1 ...
user127725
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Should I connect a cable's shield to the ground layer of board when it's isolated from earth?
I have a controller board powered by DC that may or may not be isolated from earth ground. The chassis of the device is non-metallic.
This board connects through a long (30-40m), shielded cable to a ...
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grounding a mailbox - isn't it already grounded?
I live right next to some suspended power lines. My mailbox is very close to them, and anytime I touch the mailbox, I get a mild shock. It seems to me I need to do something to ground the mailbox but.....
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Why do some electrical devices have a ground and others don't?
I noticed in my kitchen that the toast oven and the range hood had a ground fault, first by using a voltage detector pen, when getting near it the pen would activate from a distance (around 5cm ...
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How can I check if I'm properly grounded?
I figured that if I used my trusty ol' calibrated Fluke 77 multimeter and:
Set it to Ω measurement
Measured between the ground terminal of an electrical outlet and a bare metal pipe fitting on a ...
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Should I ground my case
I built up a LM317 power supply which is working great.
I have moved it into a large case as I am now powering it off 240VAC (fused) down to 18VAC then rectified into the power supply. Which is going ...
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What is the effect on noise immunity of a floating shield on a shielded twisted pair
We have an installed system where resistive sensors are connected to some electronics by shielded cables of between 2 and 10 metres. The cable is a twisted pair sheathed in a stainless steel braid. ...
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current path into the ground?
Considering a monopolar HVDC system, with the ground as the return path.
I was wondering if the current path is physically speaking like the red one or the green one in the picture? I think it is like ...
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How do I verify if a conductive mat is getting "Earthed"
Explaining to me about electricity is like explaining to your Grand-Ma about it. So please be kind and gentle :)
I bought an Earthing Mat from "http://www.amazon.com/dp/B003RLOBOK". It includes a ...
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Grounding the chassis with capacitor
My question involves chassis grounding to earth ground.
My PCB circuit is a simple signal generator using a microcontroller. It has a separate 'ground' from earth ground, supplied by a floating 5VDC ...
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local/bench earth leakage for testing mains electronics
I sometimes find myself testing switch mode power supplies and such that I have repaired, and often some undetected fault causes them to trip the earth leakage breaker on the distribution board when ...
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What is a short-circuit proof cable?
German norms and standards (VDE 250 Teil 602) specify, that wires and cables, rated for 3kV can be considered as "short-circuit proof" and "earth-fault proof" in low-voltage ...
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Why conceptually we connect circuits to earth but in reality that doesn't really work?
This question is best seen with an image:
Above we can see two equivalent representations of a circuit, on the left side we have a voltage source closed-loop connected to a Resistance (R), and on the ...
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Why does the Earth's electric field affect things so little?
Starting here:
http://hypertextbook.com/facts/1998/TreshaEdwards.shtml
"Over land the average electric field is about 120 V/m …. Assuming an exponential increase of the conductivity with altitude, ...
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Is it okay to short earth and neutral pins in 3 pin sockets?
One of the plugs in my room did not have any wires attached to the earth pin. Whenever I connect any device that has a metal casing, I get a tingling feeling if I brush my hand against the casing. I ...
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Right way to couple DGND to Chassis ground
So we all know certain things:
DGND (and subsequently AGND) needs to be coupled to Chassis ground, or Earth at one position, at least, in a device.
The Earth is otherwise considered as a hazardous ...
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Oscilloscope ground clips sparks while connecting to power supply
Oscilloscope ground clips sparks while connecting to power supply ground. I do understand The clip is connected to earth ground. But why does it not spark when I am powering a circuit of the supply?
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Strange Earth Voltage Reading
Ok, my first question here. In my spare time, I run a small PA company. On Saturday, I had a concert at a sports center where I´d never been before. Power for the event came from a standard 5-pin, 16A ...
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Is it OK to have a connection between 0 and PE on a DC device?
I have a device meant to be used inside electrical cabinets. It has a metal casing and is powered by 24V DC. It has three power connectors: 24V, 0V and PE.
I was surprised to find out that 0V and PE ...
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Earth Ground Portable Generator
I recently bought a pure sine wave 2kV portable generator to use for camping. In the manual it states that the generator should be grounded to actual earth through a metal stake and then attached to ...
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Modding a Class II switch mode power supply to have output dc- shorted to earth
As above, what are the disadvantages, risks and dangers involved in modding a class II switch mode power supply i.e. a double insulated laptop charger that is ungrounded to have the dc- output shorted ...
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Earth pin in a 3-pin mains plug [closed]
I bought a new pressure washer online and it has a 3-pin plug as shown in the picture, but there are only two pins protruding out from it.
The two pins fit into my standard 3-pin socket and it works ...
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How to mount a toroidal transformer in a waterproof plastic case
I have a toroidal transformer with mains input and 24V output, which I want to mount in an IP65 ABS plastic case. The transformer comes with two rubber and one metal disc for mounting, along with a ...
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What is the potential of earth relative to mains live and neutral? [duplicate]
I'm confused about the theory of earthing in mains electrics. In particular, how the potential of "earth", the ground or literally the soil beneath my feet relates to the live and neutral ...
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How the (earth) ground works?
I have developed bad intuition and a lot of misunderstanding about how grounding works.
For example, in this thread: Will a battery connected to the Earth eventually deplete?, the accepted answer is ...
