Problems related to the connection of circuits to ground or earth references. Can affect safety, accuracy, reliability and interfacing.
Questions tagged [grounding]
1171 questions
133
votes
6 answers
Should chassis ground be attached to digital ground?
I'm working on a PCB that has shielded RJ45 (ethernet), RS232, and USB connectors, and is powered by a 12V AC/DC brick power adapter (I do the 5V and 3.3V step down on board). The entire design is enclosed in a metal chassis.
The shields of the…
cdwilson
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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 the multimeter with currents.
Why are so many…
Transient
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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 - both the same case, but with neutral not tied to…
DSWG
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Why is an Ethernet cable not grounded?
There is no dedicated GND in the classical Ethernet 8P8C ("RJ45") pinout.[1]
Why does the Ethernet spec not include a ground, unlike many other cable types used for interconnecting devices that may both have its independent power source as well,…
mykhal
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Competing PCB Crystal layout recommendations
This is related to this question: How's my crystal oscillator layout?
I'm trying to layout a 12MHz crystal for a micro controller. I've been reading through several recommendations specifically for crystals as well as for high frequency design.
For…
helloworld922
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39
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4 answers
Reason of multiple GND and VCC on an IC
What is the reason that most of ICs (e.g. MCU) has multiple (A/D)GND and (A)VCC pins?
If it is to increase performance of an IC, how does it help to performance? or is it easier for the IC designer to connect some pins externally?
some footprint…
Angs
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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 devices by connecting it to the case (cover)?
Can…
Michael George
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Is it a bad idea to plug the other end of ESD strap to wall ground?
I have gone through this answer on Superuser, while it provides good information, I still have a specific question from electrical/electronics engineering point of view.
Is it wrong and unsafe to connect the other end of the ESD wrist strap to the…
rajeev
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Noise reduction strategies in electrophysiology
When recording electrical signals from cells (in a dish or inside a living human or animal body), one major problem is to increase the signal to noise ratio.
These signals are usually in the 10uV to 100mV range and are generated by very low power…
Ali
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Why the arc when bonding-on during high voltage repairs?
When working on high voltage power-lines via helicopter the technician will "bond-on" with a steel wand called a hot-stick. During this process an arc is conducted from the line to the wand. Now, since the helicopter is floating both literally and…
Salbando Jones
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When to use ground plane cutouts?
I've been reading more about proper grounding techniques and using ground planes.
From what I've read, ground planes provide a large capacitance with adjacent layers, faster heat dissipation, and reduce ground inductance.
The one area I'm…
helloworld922
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22
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How to safely ground a switching power supply with floating outputs?
I just received a 120VAC to 5VDC (20A) switching power supply (the kind with a passively ventilated metal casing) for use with a microcontroller project I'm working on (driving long LED strips).
I've wired up Line-Neutral-Ground correctly to a…
MartyMacGyver
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21
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How does earthing work when earth is dry?
Earthing is meant to provide reliable contact of an electric appliance to earth so that if there's an insulation fault current goes into earth instead of through a person's body. This requires earthing to be made of thick conductors driven deep into…
sharptooth
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How could using an ungrounded appliance with a grounded extension cord be a fire hazard?
I came across a tweet recently:
Don’t even THINK about using a 2-prong plug in a 3-hole slot! Use
only the required number of slots in an outlet or power strip.
Below was a picture of a burned-out grounded extension cord.
I'm hesitant to argue…
0xDBFB7
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Isn't my ground different from the factory's ground?
My understanding is that ESD safety things (mats, wrist straps, specially marked soldering irons) are designed to bring everything that can touch a component to the same electrical potential energy – ground.
But it seems unreasonable to expect that…
Maxpm
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