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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Grounding issues when using multiple supplies
I have a few questions about how grounding on a PCB and to an enclosure should be done when using multiple supplies. I have read a number of similar questions/answers from multiple sources with the ...
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Ground loop impedance when measuring pH of salty/conductive liquids
I have a reservoir of conductive liquid (~2000 μS). Inside that liquid are two sensors: a pH sensor and a conductivity cell.
The conductivity cell is a two-terminal device and submerged. When ...
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Why is the line-to-ground voltage half of what it should be?
Our electric power provider delivers 240 V, 60 Hz split-phase power to residential buildings. I've been checking our three-prong receptacles and I normally get the following measurements:
line-to-...
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1
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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 are computer displays Class I devices but TVs Class II?
I was wondering why all computer displays I know are Class I devices, or at least come with a Schuko plug, while all TVs I know are double insulated Class II devices?
I understand it might have ...
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Grounding balanced secondary isolation transformer for EMI suppression
simulate this circuit – Schematic created using CircuitLab
Which is the best secondary connection to clean the main line power from EMI, line noise and HF harmonics by using an isolation 1:1 ...
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Does regularly spaced via stitching contribute to standing waves on an RF PCB?
Should vias be irregularly spaced? Can consistent spacing between ground vias create standing waves.
Has anyone ever heard of this? I've been doing this for awhile and I've never heard this and ...
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Separating the grounds for sensitive signals
I'm designing an op amp based phono preamp. It has very high gain (60 dB for 20Hz, 40 dB for 1kHz) and the signal from phono cartridge is very low (like 5mV amplitude). So it's a very sensitive ...
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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 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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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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Designing a mains powered device in metal chassis, EMC/EMI/ESD/safety considerations for CE testing
I hope this topic is not too broad. I will formulate it as specific as possible.
I have read many articles and guides about EMC testing, but I am still unsure whether I am overlooking something ...
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Creating battery pack with biased thermistor resistor network. How to ground if sensing externally
I designed a battery pack board for a customer that uses a multi-cell low-side (NMOS) protection IC. The protection includes OV, UV, OC, and OT/UT protection for the pack. The Overtemp and Undertemp ...
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Grounds in a linear bipolar power supply for audio?
I've purchased a linear power supply, as surplus, from a local electronics dealer. It's a Condor AA15-0.8, made to supply ±15VDC at 0.8A or ±12V at 1A; as far as I can tell, it's a standard regulated ...
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Protecting External Connector Ground Pin from ESD
I have some TRS (stereo phone) connectors on my protable USB device (no earth ground), and I'm wondering what to do about ESD events that enter the device via the sleeve (ground) of the connector.
...
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Non Inverting op-amp grounding
I have this LM358 op amp as a non inverting amplifier used for high side current control.
I feed this ic with 5v on pin 8 and ground is pin 4.
Pin 2 and 3 are the inverting and non inverting inputs. ...
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Bonding Electric Vehicles: Which System to Implement (safety)?
I am currently working on building an autonomous electrical vehicle and would like some input on which bonding system would be safest and most practical. The system battery is 48V (dc) and which feeds ...
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Connecting a multi-PSU server on different lines with different earthing
I am currently preparing to set up a new server which has two PSUs (for supply redundancy). Of course it would be logical to connect them to different sources, but the situation I'm dealing with ...
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Why should the primary winding of the transformer not be grounded?
I've been wondering what would happen if you grounded both star points of a Y/Y connected transformer. This shouldn't affect the voltages, so why really is it not advised to earth both the primary ...
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Flyback Transformer - Grounding the Ferrite Core
Today I dismantled (I hope this is the correct verb) a flyback transformer. The thing that I've never seen is that one end of one of the windings is "glued" to the ferrite core (Before you ask; yes, ...
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Conductive or insulated motherboard-standoffs?
AFAIK it's common practice to mount an ATX motherboard to conductive brass standoffs inside the case. There are even metal traces around the screw holes to provide contact between the screws and the ...
user127725
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How to calculate the earth fault current in a transmission system with no ground wire?
Background information, and my thought on the matter are provided in the end of the question.
I need to calculate the fault current in case a fault occur for instance 10 km away from a transformer ...
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Grounding with a battery-powered differential amplifier
I have made a simple battery powered instrumentation amplifier (based on the AD8429 chip) for some very low noise measurements.
The rough circuit diagram is below.
Note that the BNC input is isolated ...
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1
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Advice for Grounding and Shield Placement
I am working on a board design which includes an ADC and a DAC. The board attaches to the headers of the Mojo V3 Spartan 6 FPGA Dev Board. The ADC has to pick up a quiet signal at the same time as the ...
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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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What is the safest and most noise free grounding method floating or non-floating for audio plugs & circuits on 2U aluminum case and SMPS
I have read countless documents and viewed schematics on this subject but am still confused when it comes to physically building a box and running all of the wires correctly and safely.
I drew a very ...
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How to properly ground an old turntable and tonearm?
I have a specific question about proper grounding of an old turntable that hopefully has some general merit for such older devices.
This question came up while I was inspecting the wiring of the ...
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Managing seperate ground paths for a driver
I'm trying to design an add-on board for a single board computer, similar to an Arduino shield or a rPi hat. Among other things, the board will control a couple of inductive loads through a ULN2003A ...
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How to correctly ground/isolate a grounded enclosure type thermocouple?
My K-type thermocouple (grounded enclosure type) connected to MAX31855 adapter connected to Arduino Mega gives me faults every few readings. It's really, really bad. I've tried swapping thermocouples, ...
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Making earth pit in swampy area
I recently made an earth pit in a swampy area. I dug the earth up to 5 feet as water was available at 4 feet depth. I poured charcoal and salt in the ratio of 3:1 . After braising the copper plate ...
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Chassis and digital ground in an eight layer PC motherboard
I have GNDC (chassis GND) and GND (digital GND) on my PC motherboard design.
All connectors in my design (RJ45, USB-TypeC, USB-TypeA, HDMI, DP, etc.) are connected to the chassis through the GNDC ...
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Does filtering and protecting the ground with an inductor, capacitor, and TVS have a benefit?
Let's assume a situation where you have a symmetrical power supply with the following output (in bracket is the net name, see the picture):
+15V (+15V_DCIN)
-15V (-15V_DCIN)
GND (GND_DCIN)
Earth (GND ...
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Why are conductive chassis double insulated appliances allowed in the UK?
MacBooks are infamous for 'buzzing' to the touch while charging. If another (properly Earthed) laptop touches one, it can flicker the screen or shut down. If I plug one of these same properly Earthed ...
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Should I install a dedicated earth connection for an antenna?
I was tasked with installing a point to point antenna on a monument. I have read in the dish's manual that it should be connected to earth for optimal performance.
My problem is the power that goes ...
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What are the correct signal ground connections in an RS485 system with a shared ground on motor drivers?
I'm in the process of designing a motion control system using RS485 and whilst we've generally made things work in the past with a more trial and error approach, in the interest of doing things right ...
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Yacht generators with common neutral - Voltage Balance & Harmonics
In a marine application, a yacht using two generators (not connected in parallel), to feed 7 separate circuit panels, separated disconnects but common neutral.
Both generators have their neutral ...
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How to prevent grounding issue on Mini DisplayPort
I am attempting to design a board that has a Mini DisplayPort output.
When I plug a Mini DisplayPort cable into the board and measure the ground (system ground against Mini DisplayPort shield,) I get ...
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Metal antenna enclosure and grounding
I have designed a device with a metal enclosure. It has an external antenna with a connector mounted on the box.
The antenna ground and box are connected. Moreover, the antenna is mounted on the ...
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Is it bad practice to connect a heatsink to my PCB's ground plane?
So, basically, I have this LED project which is going to dissipate lots of heat (I am assuming close to 50W) inside a case. The LEDs themselves are on a separate aluminum board which will be attached ...
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Connecting grounding mat to socket
I bought an anti static mat that came with a banana plug connector and an alligator clip that can be mounted on the banana plug. Can I connect the banana plug connector directly into a US ground ...
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How parallel plates are buried in the soil in real life?
From this site:
The most common reference is Earth itself. Power systems are usually
“earthed” at some point to provide a reference for the system
voltages. The earth symbol represents the parallel ...
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Is it okay to use metal to house a thumbdrive?
I have an opportunity to craft some novelty thumb drive housings. A number of these consist solely of the 4 contacts on plastic and the metal ground housing, similar to this (with out plastic cap)
Can ...
user255757
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How does this soldering iron sleep sensor circuit work?
I recently built a unisolder soldering station and am struggling to understand how the detection of the soldering iron within its holder is implemented. The unisolder board itself provides a 3-pin ...
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Why is there 10VAC between me and a gas oven, 50 VAC between me and an electrical oven, and 110VAC between electrical oven and gas oven?
I have a gas oven which connects to a metal gas pipe, this oven can be considered grounded through the gas pipe, (the oven is not grounded in any other way).
I also have an electrical oven which does ...
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How do I properly ground DC and AC in the same enclosure (DIN rail)?
I am building an electrical panel with AC and DC supplied power. My AC ground wires connect to a green DIN rail connector which has metal on the bottom of this terminal and connects to the DIN rail ...
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IEC 61000-4-5 2 kV chassis ground to neutral and live surge DC
I need guidance for passing the IEC 61000-4-5, 2 kV Surge test from the AC ground (protective earth, PE) to the neutral and live wires. This grounding techniques may be a bit different that passing ...
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How do I test grounding/lightning protection?
I manage IT for several clients in Central Florida, where we have quite a lot of lightning (the most in the U.S.). I have one client that has trouble keeping electronic devices alive. We have replaced ...
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Adding Ground or Earth to the shielded cable
I am using 8 core shielded cable to transfer I2C signal along with analog sensor data. We have connected earth to the shied cable, we have option to connect DC ground also. Everywhere I have read ...
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SMPS Grounding and Earthing
I'm trying to design the isolated SMPS circuit. I'm a newbie on power electronics and I'm using a circuit design tool to design SMPS. I have confusion about grounding and earthing. My system will have ...
