Questions tagged [grounding]
Problems related to the connection of circuits to ground or earth references. Can affect safety, accuracy, reliability and interfacing.
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Earthing: TN in TT installation?
Something odd happened at work today: the whole building installation is TT, just like the whole country. L1-L2-L3 supplied to the transformer and then L1-L2-L3-N goes to the loads.
I noticed that we ...
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Earth for custom POE+ board design
after getting the center tap pins for poe, I have an example schematic to design an EARTH ground. I have the understanding that that would be our Earth in AC over cabinet. That would remove our value ...
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Why would a low-pass filter be connected to +5V on an RS422 differential line?
I am interested in a datasheet's schematic for my own PCB design of a similar system.
In my system, I am receiving an RS-422 differential line, and would simply be tempted to put a 100 Ohm terminating ...
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How to connect cable shield when receiver side powers signal source?
I have element 'A', the receiver, connected to earth, which powers modules 'B' and 'C', the signal sources, unconnected to earth. 'B' sends a differential line signal, and 'C' sends an analog signal. ...
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Grounding in power electronics
I'm designing a three-phase inverter and have been looking up information online with respect to grounding, which led me to a somewhat misapprehension.
In my system I firstly planned on separating the ...
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Charge leakage in home appliances [closed]
I have a basic question which isn't cleared through answers found.
We experience a slight electric shock in case of home appliances like fridge, oven etc. when we touch the metallic parts of those ...
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Connecting GND to PE to improve touch sensors sensitivity
I am designing a smart light switch based on a microcontroller, with touch buttons. The design consists of two PCBs: a low voltage one for power (230 V) and an extra low voltage one for control (3.3 V ...
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What is the actual physics and reasoning for the “Ground plane” underneath a GPS patch antenna
From my very limited knowledge of EM, I believed that anything tied to earth can absorb radio waves, so if an antenna was to be placed above a ground plane, why does the ground plane not just absorb ...
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Amplifier chassis noise when not earth grounded
I build a kind of audio amplifier (it's actually a mixer). The problem is that the output gives a high frequency pitch noisy sound as soon as I touch the front panel which is part of the chassis. It ...
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Effect of the placement of ground electrode on ECG
The above figure shows two ECG signals recorded after placing the positive electrode on the left palm and the negative electrode on the right palm. For the recording on the top column, the ground ...
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What is an ungrounded extension cord? Is it dangerous?
The definition of a grounded extension cord from this website is:
If you have a three-pronged extension cord, it is grounded.
Why is that so? What do we mean by "grounded" in this case?
My ...
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Can Y-Cap Remove DC Offset between Grounds?
I ask this question because I saw this in an Altium article:
In power systems, be careful how you use a capacitor to ground to ensure a consistent ground reference. Y-rated capacitors are best in ...
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EU appliance use on US circuit - grounding concerns
I've been reading through old posts about people wanting to use European kettles and other appliances on a 240v US circuit. Forget the 50hz/60hz frequency difference for resistive loads and universal ...
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Ground isolation in multichannel mixed-signal systems
There are some similar questions to mine but I have a few more specifications on top of them. Therefore, I am not 100% sure whether to ask as an iteration or present my own question on a clean slate. ...
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Is it always given that ground has lower resistance than output even If output is far closer in an inverting nmos? [closed]
Currently I'm learning about MOSFETs (N-MOS and P-MOS) --basically how a transistor works. My question is why does the current always prefer the grounding output even though it is further away than ...
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Grounding Case to AC ground causing IO errors on PCB [closed]
I have a PCB that is powered by a AC/DC power supply. The PCB also has a aluminum heatsink attached to it. This setup functions normally when outside it’s case, as soon as the PCB and psu is mounted ...
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Neutral grounding resistor
How does neutral grounding resistor in power generation side, see and link up with grounding fault at the secondary side of a transformer?
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Earth Resistivity Test on concrete base
I am planning to conduct an Earth Resistivity Test on my property. The issue is that my building's basement is entirely covered with concrete and pavement, and we intended to use the Fall-of-Potential ...
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How should I layout an optocoupler isolation board with separate ground references and power supplies?
I am thinking about how to layout my opto-isolation board. It is used to protect pins on an FPGA, convert signals to RS-422 and then transmit via RJ-45.
I have seen some conflicting information about ...
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Grounding in a balanced audio (XLR/Sub-D) switch?
I am currently working on a switch for XLR/Sub-D connections. However I am unsure as to how I have to handle grounding. Do I have to switch the ground for each channel or can they be bundled together?
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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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Is this a safe way to use isolation transformer to mitigate neutral to ground voltage?
I work with a TN-S system wiring.
Main three phase transformer secondary is in Y configuration.
A single-phase lab instrument equipment installation requires less than 1 V for neutral to ground.
We ...
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Why grounding the circuit with external stuff, when a capacitor can do it?
I am examining my own radio circuit now for several days, so I included a pic:
When the circuit has been powered up, it works fine without fingers or equal grounding methods, for example by getting ...
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ESP32 USB Port Misadventure
I just had an incident where my laptop had two unresponsive ports and I am trying to figure out if it was my fault or a buggy driver.
Long story short I built a digital power meter for a linear PSU ...
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PCB Design multiple grounds with different ICs
I want to make a board that have differents ICs and looking at the datasheets, I can see different grounds connected in different ways and I'm not so sure about how to connect them/which ground should ...
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Adding second relay coil in parallel with the first one creates buzzing in the first
In my cargo trailer/camper conversion, I used a DPDP 120 VAC coil relay (JQX-62F-2X 80 Amp) to connect the breaker panel to shore power or to an inverter (for battery power source). The coil is ...
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Should the threaded insert for an M.2 mounting screw be grounded?
A PCB that I am working on has a non-plated hole into which a press-fit threaded insert is installed to provide the mounting point for an M.2 SSD. As such, when the SSD is installed, the mounting ...
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Bouncing ground and voltage spikes (power supply and grounding issues)
I am having an issue with voltage spikes and bouncing ground in my circuit.
Circuit is powered with 12V DC power supply. I am have two DC-DC converters:
4V output (power module based on TPS54331) 3A ...
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PCB inside metal chassis. Is chassis ground required?
I have a project that has a PCB housed in a metal enclosure. The PCB is powered by a USB-C connector. Power input is 20 V DC @ 4 A max. Power is sourced from an isolated AC/DC wall wart adapter. The ...
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Zener diode for overvoltage protection and earthing
I am designing a small circuit where the goal is to measure the current. The CT measures the current, which passes through a shunt resistor. The ADC convert the signal so it can be further processed.
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Can I use the concentric conductor of NYCW 95/50 as a ground wire?
Must one buy a separate ground cable in a TN-S network for earthing or can the concentric conductor be used for earthing purposes?
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Why are three pronged plugs more preferred than two pronged ones?
I get that three pronged wires have the earthing wire and all but unless we plug it incorrectly or something along those lines, two prongs work just fine right?
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EMC filter for two wire flyback SMPS
I am designing an EMC filter of a two wire (no earth connection) flyback SMPS.
In the EMC filter, AC line usually has two Y capacitors after common mode choke connecting earth (PE). Since this SMPS ...
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Do neutral wires go back to transformer via ground?
I have heard that transformer connects to house only via phase(s) - neutral from house is actually grounded, as well as transformers and they connect via earth. Is this true? What is resistance of ...
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With modern connectors, is the metal shell used as a conductor?
Does the metal shell of a connector, such as USB and HDMI, serve a conducting purpose? The metal shell of my TV's HDMI terminal is corroded. Should I make effort to have it contacting and conducting ...
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Why does AS3001:2008 Transportable Structures explicitly deny a separate earthing electrode?
As the title says, if a generator is providing a TNS earthing system connected to a transportable structure through a detachable connection, why does AS3001 state:
Isolation of the protective earth ...
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Why does my RCCB keeps tripping every time I want to start a 3-phase motor?
I am working on a filtration pump using a simple start-stop button for the 3 phase motor Electrical diagram is attached below. Most of the main components are from Schneider. The "Pump Run" ...
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Alternative to P-JFET design to ground load in case of low supply voltage
I'm working on a device and I'm encountering some problems. Basically the device pushes varying currents through a variable load using a current source and an H-bridge. For safety purposes, the load ...
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Grounding and Ground Pour
I’m trying to build my first audio amplifier and need some help and advice on this topic.
It will be a simple 100 W audio amplifier, powered by +35 VDC and -35 VDC. There will be local power ...
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Stack up and inner layers of shield structure used in RF PCBs
In such RF PCBs, it can be easily seen that the chassis ground passes through the middle of the PCB. My question is, is the chassis ground directly connected with the signal ground in such RF PCBs? I ...
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Adding a Chassis Ground at the Midpoint of a PCB
The PCB I designed is 6-layer. I will create a chassis ground in the form of a frame surrounding the mounting holes and add a Y capacitor between and to the signal GND. And I will surround this ...
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Different Ground reference
I plan on making my own BMS for a 12S battery pack, and I found TI's TIDA BMS board and decided to use it as a reference to gain some understanding on how to develop safety circuit for the board. ...
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Can COM and earth be connected thorough the PCB ground pin?
I'm using an AC/DC switching supply (Meanwell PD-45) with the following schematics:
The Frame Ground (FG) is connected to the metal chassis of my device with a screw. The output of the switching ...
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Earth ground and DC
If I understand correctly, a DC circuit powered by a simple battery would not be affected in any way by an earth ground. By earth ground, I mean a copper wire attached to the ground through a long rod ...
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Separate ESD traces/layer?
I am designing a keyboard that connects through USB-C to a computer and has Aluminum chassis. I am dealing with ESD protection for the enclosure itself and some exposed components (that have a "...
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Inrush problem while using a isolated DC lab power supply
I'm puzzled by an issue I've been observing during my testing of H-bridge buck converter.
I'm using 2 lab bench DC PSU such as E3630 (Keysigh)t to supply ISOLATED 5V to a driver.
When I power up the ...
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Will I see a sine wave if I connect one oscilloscope terminal to the phase and another to the earth?
I have a doubt regarding a thought experiment I am conducting since I lack access to proper grounding at both my workplace and my house.
The experiment involves the following setup:
I intend to ...
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Split or not split the ground plane in a low-noise design?
For low-noise design, many component datasheets suggest dividing the ground plane into AGND and DGND and linking them with a star connection.
But my ten years of experience in EMC have shown me that ...
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How does chassis ground apply in nonmetallic enclosures?
I am working on a PCB that uses a chassis ground, but I am not able to make a metal enclosure for it. I was wondering if you can use enclosures that are not made of metal for chassis ground and how it ...
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Cost-Effective yet reliable earth detection circuit with <100µA current draw
I'm working on a cost-effective circuit to detect the presence of an earth ground connection in a 230V AC mains line (at 50Hz). One of the key design constraints is to keep the current draw less than ...
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