Ground or earth is the reference point in an electrical circuit from which other voltages are measured, or is a common return path for electric current, or a direct physical connection to the Earth.
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32 views
Which wires goes to appliance's ground and on/off switch?
I have an electric hair trimmer whose power kept getting interrupted. I knew the problem was in a particular spot in the cord because when it would bend there, the trimmer would lose power. I cut ...
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2answers
70 views
Difference between Ground and Digital Ground
While working with circuit simulators, I often come across two separate grounds:
Groud
Digital Ground
What is the difference between these two?
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0answers
89 views
Pushbutton Ground Selection
I need some ideas for a pushbutton ground selection circuit.
I want to be able to switch grounds using momentary pushbuttons. I could do this simply with a rotary switch, but due to design I'm ...
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1answer
162 views
Does a power supply GND connection need a resistor?
I am creating a power supply for my work station, and I have a input of 13.5 - 19V DC from a converter on POWER_JACK.
From this input voltage I want to derive 12V, ...
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3answers
127 views
Single terminal of voltage source attached to earth ground
This is a conceptual question I continue to struggle with as I have started studying electronics.
Say we have a battery, and one of its terminals is connected directly to a nice patch of highly ...
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1answer
88 views
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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2answers
152 views
Why do we connect a battery to ground when jumping a car?
This may seem like a very simple question, but I've searched all over the place and haven't found an answer.
When jumping a car, we connect the + end of the charged battery to the + end of the dead ...
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2answers
116 views
Can a pull down be used to tie a line to ground?
From my recent introduction to pull-up/pull-down resistors, I understand that an input with a pull-down will stay low instead of floating. Since the pull-down resistor leads to ground, couldn't I ...
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2answers
90 views
Regarding Return currents of the traces in PCB
This Question very basic and may be dumb question..
I remember for every trace a return current will flow exactly under it(minimum inductance path) or shortest path(minimum resistance).
I have a 2 ...
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1answer
100 views
Grounding in a DC circuit on a vehicle
I am working on a vehicle with batteries, but i am not quite sure if my grounding solution/design is correct. It is supplied with two 12VDC batteries in series, connected to a DC-DC (24VDC-24VDC) ...
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2answers
92 views
Multiple Voltage Sources using a single Ground
I'm having a hard time understanding how a circuit can have multiple power sources and have them all tied to the same ground. See the following schematic as an example:
Here's my current thought ...
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3answers
101 views
Does a ground fault compromise the whole circuit?
(this image taken from http://www.allaboutcircuits.com/vol_1/chpt_3/3.html)
Based on this picture, would a tree across the bottom wire of the circuit (the solid wire, not the dashed wire ...
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2answers
60 views
How to trade off connection styes in mixed gnd systems( power gnd and signal gnd)?
I am using a motor driver L6235 from ST:application note.On page 6, it gives me a layout suggestion:
it says that the SIGNAL GND and POWER GND should be connected in a single point: the negative ...
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2answers
110 views
Problem of noisy ground
In this design, the 2A motor "M", which is running at PWM=10kHz, creates a lot of noise in the ground as shown on the scope trace. Not only the ground is sinusoidal but more painful, the ground level ...
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1answer
73 views
Powering off USB - question about grounding
I have a female USB connector that I want to use to power a little piece of electronics I'm working on.
I have a USB cable plugged into a computer with the socket on the other end and I'm using my ...
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1answer
76 views
Connect different devices (Ground/Voltage mismatch)
To begin with, I realize that voltage is relative but I do not get how to get a common ground so that everything is relatively correct to go in and out of the chips.
The picture summarizes the setup:
...
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3answers
108 views
Breadboards and ground loops
The book Practical Electronics by Scherz and Monk states (3rd ed., p 48):
A ground bus, or bus bar found in breadboards... serves as an adequate substitute for a single point ground.
Is this ...
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2answers
92 views
Best practice to switch +V or GND connection?
Consider LAMP1 and LAMP2 in the simple example circuit below:
Which is the "better" practice, using the switching component ...
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3answers
424 views
Use of ground symbols in circuit diagrams
In this question is the following diagram for a voltage booster intended for small battery powered devices
The TPS61200 spec says GND is control/logic ground and PGND is power ground but this isn't ...
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1answer
38 views
Choosing a ground for ltspice circuit
I am just getting into this software. I construct my circuit, and it tells me to choose a ground. I only have experience with "ideal" circuits and circuit elements, and have only seen "ground" in the ...
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2answers
332 views
Can you send data usefully over one wire, literally one wire?
It is possible to design networking systems that only use two wires: one for data and one for a common ground. Examples include 1-wire and Pin&Play. These are called single wire systems because ...
3
votes
2answers
120 views
Why are leads from the negative terminal considered grounds?
I'm using a 9V battery with a 5v regulator as a power supply. What I can't grasp is why I place the regulator in the (+) lead of the battery. If electricity is electrons flowing, and the excess ...
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1answer
107 views
Ground Fault Question Regarding a 3 Phase Circuit
I'm needing to design a 3 phase ground fault detection system for a 480V system. It will need to be able to trip when there's ground fault current >1A.
I have done some reading and it sounds like ...
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2answers
173 views
Do 2 5V DC wall warts in the same AC outlet have a common DC ground?
I'm trying to power a LED strand from one wart (5V), and my logic driver FPGA from another wart (also 5V). Both warts are plugged into the same outlet strip. I know I should probably power them from ...
3
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1answer
151 views
Power Plane and Decoupling Capacitors Routing
Forgive me for my simplicity. I'm just a hobbyist and not an engineer by trade.
I am trying to make my first 4 layer PCB in Eagle and I have a question I cannot find the answer to regarding power ...
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2answers
184 views
Transistors never work for me
TOday, I have built an LED cube. I put it all together, arduino, mess of wires and all, and it doesn't work. Fiddling with it a little bit, I find that if I short certain wires to ground, the LED's ...
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2answers
100 views
DC Voltage Grounded with AC Input
This is an image from a book showing us how to solve BJT circuits via AC analysis:
So I understand that when doing AC analysis to ground all the DC voltage sources but I don't understand why. Can ...
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1answer
131 views
Tying multiple power supply grounds
I'm planning on a home automation system, and two sub-sections will be separated by (say) 100 feet. These will be connected by a low-amp, low-voltage data connection. To avoid running significant ...
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3answers
220 views
Ground on Breadboard
I need to connect an input signal from a function generator to a circuit I made on a breadboard.
If I use a BNC to Banana cable, then would the "ground" of the function generator (the ground on the ...
3
votes
1answer
107 views
What's the use of ground coupling on digital oscilloscopes?
What's the practical use of ground coupling on modern DSOs? I know that it can be useful on analog oscilloscopes to adjust the ground exactly to a graticule line, but from what I've seen, most of the ...
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1answer
110 views
How do I wire a relay board into existing series recepticles
I have a four channel relay, that I'm going to attempt to wire into a terminal block. I have experience with mains wiring and some experience with electronics, but no experience wiring relays. ...
2
votes
2answers
220 views
bridge rectifier connected to a raspberry pi gpio
I'd like to connect a bridge (full wave) rectifier to my Raspberry Pi (RPi), GPIO pin 22 (configured as an input). I have configured the rectifier such that it has a 120VAC input and 3VDC output (I ...
4
votes
1answer
97 views
How do I connect a signal shield to minimise noise from close proximity AC
In my proposed application, I will have approximately 30 RS-485 nodes configured in 3 chains spaced ~1m apart. There is a need to pass through 240v L-N-E, +5v, A, B, GND in each node. The physical ...
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1answer
154 views
How does this heavily oxidized copper-to-steel joint work in earthing?
Wikipedia article on grounding features this photo:
Here's a close-up of the joint:
Clearly the steel rod is heavily oxidized and the copper wire is oxidized. The clamp is coated with something ...
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2answers
270 views
Grounding and why charge leakage occurs
A basic nugget of info is missing in my end-to-end picture of how grounding works and why it's important. When a voltage is applied in a circuit the electric current starts flowing (or the field ...
3
votes
1answer
150 views
Two power sources, common ground and noise
I'm having the following circuit:
Where TWL6030 is a DC-DC buck converter and INA219 is a high side current sensing circuit.
My problem is with the power sources,...
3
votes
2answers
218 views
Grounding in circuit diagrams
Often I see in circuit diagrams that the circuit is connected to the ground:
I understand that this creates a reference for zero potential, but why does all of the current not simply flow right ...
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1answer
946 views
Y USB Cable with external 5V supply
I just got a brand new Nexus 4 phone and am a bit dissappointed that it doesn't support USB OTG. One reason is that is doesn't supply 5 V out of its USB port, as opposed to other Android devices I ...
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1answer
84 views
Confused about the way this speaker is wired
From this article:
I don't understand why one end of the speaker is connected to the + of the battery. If the output of the 555 goes into one end of the speaker, shouldn't the other end of the ...
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votes
2answers
405 views
What is ground and what does it do?
I'm a bit confused about the concept of ground, and perhaps voltage as well, particularly when trying to analyze a circuit. When I learned about Ohm's law in grade school, I learned how to apply the ...
5
votes
1answer
257 views
How is the following ground symbol different from conventional ground?
I've seen the following ground symbol in quite a few schematics:
How is this different from the typical GND symbol?
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1answer
90 views
Is using Same Ground and VDD for MCU and motor driver module safe?
Im trying to design an MCU prototyping board. i have 2 voltage regulators (3.3 and 5V) and motor driver on my board. All grounds are common, VDD of MCU comes from 3.3v reg and power supply for motor ...
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1answer
139 views
Shared GND on 2 ATX Power Supplies
I'm constructing a custom(cheap) power supply, with digital current meters and such.
I'm using 2 ATX power supplies to build it. I'm using 1 for the standard -12, -5, +3.3, +5, +12 outputs. I've ...
8
votes
3answers
2k views
Help me understand the relationship between positive, negative, neutral and ground in AC and DC
This question stems from notations on schematics and seemingly conflicting information I'm seeing. I suspect that I'm seeing different vernacular for the same concepts--but I'm in a place where no ...
7
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2answers
486 views
How do you properly ground a digital pot and an op-amp?
I'm going to take a 5V 500mA power supply and pass it through a digital potentiometer AD5235 and then step it up through an op-amp with a gain 2 to get up to 10V output and put that into voltage based ...
2
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4answers
187 views
Common ground and voltages, Part 2
To further my understanding of what happens when 2 circuits have a common ground could someone please explain what happens when the following 2 circuits (charged capacitor, high resistance load) :
...
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3answers
552 views
Common ground and voltages
Further to a question I asked earlier, I realised that common ground confuses me. I have a USB powered Arduino and a separate Battery supply. The battery supply negative is connected to the Arduino ...
7
votes
1answer
215 views
Ground noise and voltage drop problem
I have an RC device powered by a 3.7V poly battery, which includes a motor and a 40KHz sonar. The voltage across the sonar sensor is amplified and then adc-ed. The motor is driven by a 2KHz PWM.
When ...
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1answer
218 views
USB ground on MSP430 Launchpad interfering with Comparator_A input voltage
I'm trying to read an audio signal from an Android phone as a serial input to an MSP430G2553, adapting this design to use the MSP430's onboard comparator module instead of an LM324. The Android code ...
4
votes
1answer
130 views
What is the right way to understand the behaviour of shocking voltage?
I am just a starter and I am reading some beginner material about electricity.
I have some problem understanding this page which was about shock current path.
The writer explained why the bird is ...
