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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Do I definitely not want to to add a ground wire to this UART connection?
I'm in a bit of a quandary here but it must be a common one. I have two boards powered from the same battery through a "Y" cable; both boards have voltage regulators on-board. These boards are ...
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1answer
24 views
Separate ground for gate opener control box?
Is it worth electrically isolating the control box of a gate opener from a well grounded steel fence? Or does the grounding of the fence have the same effect?
My house is in a very lightning prone ...
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3answers
77 views
Why does low power factor make my LED bulb and clock radio flicker at 0.2 to 3 Hz?
[California, USA, regular 110 V power.]
I'm reading the power factor of my "Late 2013" 27-inch iMac using a P3 P4400 Kill-A-Watt. It reads 0.95 when operating normally (60 to 120 W), but when ...
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52 views
PCB Grounding Plane Review
I am reviewing a 6 layer board that has analog signals on the left and right side of the board.
I have always read that analog circuitry should be grouped together for easy plane segmentation. ...
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1answer
46 views
Can a ground fault be caused by something outside the home?
Yesterday afternoon, I had a GFCI switch trip. It would not reset. I figured I had a ground fault.
I left the home for a few hours and after I returned I was able to successfully reset the GFCI.
The ...
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3answers
68 views
where to place grounds on a circuit
I'm used to seeing circuit schematics with single/no grounds at all (drawn by teachers and some tutors) but now, I see circuits with multiple grounds. My question is, when drawing a particular ...
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2answers
454 views
What is the purpose of this extra PCB pad?
I am looking to use this crystal in an upcoming design and I am a little bit confused by the datasheet.
The datasheet is available here:
CMR200T Datasheet
This is the image in question:
Question:
...
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17 views
Not properly grounded/earthed [migrated]
I know next to nothing about electricity and wanted to ask for some advice. Apologies for any cross-posting.
I moved into a rented house in Spain a few months ago. Turned out it wasn't grounded. ...
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42 views
Analog ground/Digital ground question
I am designing a four layer PCB, (signal, ground, pwr, signal), which is to generate +-1V max 30kHz frequency signals which is output on a differential pair.
It is pretty simple board layout but I am ...
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52 views
Live Metal Enclosure Detector
I'm building a live metal enclosure detector which can detect if your appliance metal enclosure has accidental contact with the hot wire inside it (this is alternative to grounding. I know grounding ...
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1answer
34 views
Why is there a grounding clip on this solder sucker instead of a third prong on the plug?
As most of these inexpensive tools tend to omit the ground altogether (such as in soldering irons), why would ground be added as a clip instead of a third prong?
Is there an advantage for it to be ...
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1answer
78 views
Crossing ground planes with low current low frequency signals
I have a board which has two ground planes, analog and digital, that on this board are completely separate. The grounds connect on another board, which is connected via a flat cable.
All signals on ...
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23 views
Pins of DIN 43650
I am newbie in the world of electronics. So, please bear with me.
Considering the pins of a DIN 43650 from an LVDT, I have the connecting instructions as in picture 1. The data from the LVDT is fed to ...
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1answer
126 views
Grounding and Signal Integrity of my PCB Layout (ADC, SMPS, SD card, USB)
I am currently designing a battery monitoring system for an 8 cell lithium battery pack. I originally made the device using a STM32 dev board and breadboard, with an SD card to log data. The system ...
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1answer
82 views
How can charging current be understood intuitively?
The charging current I’m talking about would be the one between un-shorted phases and ground when there is a short to ground in one of the phases in a distribution network or facility. I'm not talking ...
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2answers
54 views
Will this SOI circuit be grounded?
Upfront, I apologize if this may be a terribly obvious question. I don't have all of the background to understand it confidently.
I'm trying to apply a voltage for an electrophoresis experiment ...
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1answer
57 views
Why is the usb shield always tied to ground (GND pin)?
The shielding on a cable is to avoid interference from the outside world however it is always tied directly to the GND pin. Not inside the cable itself but inside a device. Every single device I take ...
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36 views
Preventing the voltage between two isolated grounds from exceeding max rating
Consider the low-side current sensing application shown in Figure 1. Grounds 1 and 2 are galvanically isolated. Assume, for example, ground 1 is the NEUTRAL line on mains power (\$V_g\$), and ground 2 ...
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3answers
46 views
Can current flow to earth in TN-S Earthing system?
The above illustration of a TN-S Earthing system shows one shared connection to earth between neutral and protective Earth.
Assuming a short circuit occurred, in the brief second before detected by a ...
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3answers
115 views
Voltage gradient across an antenna (and how it drives an AM radio)
Edit:
I was interested how is voltage gap maintained across an antenna. It seemed to me that an antenna might be like a wire where if there's a voltage at the top, the same voltage would be at the ...
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2answers
48 views
Is grounding necessary for a re-purposed laptop charging brick? [closed]
If I have re-purposed a laptop power brick, is it important to ground it or in certain use cases could one get away without earthing the power brick?
I bought a class D amplifier board off eBay ...
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1answer
46 views
What to do with internally unused pins on a non-programmable device?
I'm designing a board for using the FLIR Lepton 2.0 LWIF camera (datasheet at https://www.flir.com/globalassets/imported-assets/document/lepton-engineering-datasheet---without-radiometry.pdf), and ...
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56 views
Correct way to do “power injection” from multiple DC supplies?
I'm using a PixLite controller to run a bunch of pixel LED strips. Since I'm sticking to 5V I need to use multiple power supplies (PSUs) to "inject" extra power for the number of LEDs I'm running. ...
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1answer
60 views
LTSpice chassis ground or earth ground
I'm trying to simulate a circuit for a design I'm making. In a few parts of what I'm interfacing with uses relays that when closed will short a few power supplies to the chassis ground and in LTSpice ...
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25 views
VITA 46.0 VPX grounds isolation requirement
VITA 46.0 VPX standard demands:
Rule 3-15: Plug-in modules shall provide a minimum dielectric withstanding voltage of 500VDC +/-10V and a minimum resistance of 1 megaohm between safety ground and ...
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1answer
84 views
Measuring soil resistivity and estimating soil equivalent resistance in a long distance
I'm trying to size the Neutral to Ground resistor (NGR) in the Wye of a 138 KV to 4160 V Delta-Wye Transformer. In order to find the proper value I have estimated the charging current of the system by ...
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1answer
16 views
MAX31865 RTD converter will it acccept only floating inputs?
We intend to use MAX31865 for measuring resistance values. Since MAX31865 is RTD to digital converter, kindly clarify whether the MAX31865 will accept only floating inputs or it can be used with ...
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1answer
67 views
“Creating” a ground pin for my laptop
I am building a sensor using an Arduino connected to a laptop; I noticed that the readout is much more noisy when I use a non-grounded laptop (either running on battery or connected to a power socket ...
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1answer
57 views
Substation grounding
I am trying to understand a grounding system for substations, fault current is something I am not getting. For example, for a small substation with some transformers, if there is a fault in the system ...
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1answer
70 views
Grounding in transistor circuits
In all example circuits using a transistor to power something (say, a motor), it seems to always be an NPN transistor (or NFET) with the something/motor connected to V+ and the collector/drain.
This ...
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2answers
102 views
Laptop fried from spark while connected via USB to a battery system
EDIT 10/11 9:40am Central:
I learned from my partner on this project I got the order of events wrong. I have edited the post accordingly.
I am working on some custom electrical hardware for ...
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3answers
71 views
Shield grounding for analog sensor
I have an analog sensor, a resistance temperature thermometer, which is essentially just a resistor (~50 Ω) which I apply a constant current to (10 mA) and measure the voltage of in order to ...
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3answers
98 views
Can lightning damage electronics via a ground connection?
Often when we think of a lightning transient, the idea is that the lightning strikes a power line and propagates through the hot/neutral or 3 wires of 3-phase system. There is also induced current ...
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67 views
Connecting all grounds directly to the supply's ground?
I currently have this layout on my PCB:
As it appears, the grounds from the different components are connected to each other and then connected into the supply's ground.
In the context of amplifiers,...
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2answers
82 views
AGND and DGND connection using flash ADC, totally stumped
So, I am designing a PCB with the classic scenario of having both sensitive analog signals and noisy digital signals...
Analog and digital regions are separated. the have their own gnd
planes and ...
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1answer
55 views
Replace a relay with an analog switch
I'm trying to replace a relay with a SPDT cmos analog switch MAX4678 for switching a sine wave, The switch is powered with dual power supply +5/-5 and +5 to its V_logic pin.
This is what i got in ...
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2answers
115 views
PCB grounding through screw head
Can we use zinc plated screws for PCB grounding?
Means the zinc coated screw head will be in contact with copper trace on PCB for grounding.
But this can cause galvanic corrosion between zinc and ...
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0answers
180 views
Why did this arduino burn out? SilentStepStick (TMC2130) stepper at 24V
I'm new to electronics.
Attempting to bench-test a SilentStepStick stepper driver board, (based on a TMC2130)
Using: Arduino Uno, a SilentStepStick driver board, a 0.6A stepper motor, and waterott ...
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1answer
88 views
How to ground electronics correctly
I'm at the stage where I'm moving a project off of a breadboard and on to proto board but i'm unsure if I should tie all of the grounds together. Is there any reason I shouldn't? It's basically 3 ...
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How could using an ungrounded appliance with a grounded extension cord be a fire hazard?
My local fire department, @Barrie_Fire, recently tweeted (then subsequently deleted) this:
Don’t even THINK about using a 2-prong plug in a 3-hole slot! Use
only the required number of slots in ...
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3answers
105 views
Why the earth attracts charge and where does the charge go when it goes into ground?
Self-explanatory question but to add what I know, by this I will also know if I am right or wrong.
I read somewhere that Earth is positively charged, but is not the state (whether positive/negative) ...
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1answer
72 views
Connect common ground stereo to a device with different ground for each channel
I have an old stereo that I want to resurrect and add Bluetooth to it. For that, I bought a Bluetooth module, this one: https://www.aliexpress.com/item/PAM8403-Wireless-Stereo-Audio-Receiver-Module-...
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1answer
73 views
Re-wiring experimental apparatus: Questions regarding proper ground, DC power supplies, and precision instrumentation
The apparatus consists of a large metal spherical chamber attached to a metal table. There are two electrical enclosures bolted to the table legs. The chamber is outfitted with multiple servomotors, ...
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1answer
130 views
Ground and earth layers on PCB
I am designing a digital board with USB input and output.
Shield of USB is connected to a chassis ground as per USB specs and connected to GND through a R and C in parallel
USB power has a common ...
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2answers
58 views
I have four wires when I cut ear buds away. Which ones are hot and which are going 1red 1blue 1gold and 1yellow [closed]
I cut some earbuds to use on something else and would like to know which are grounds and which are hot 1is blue 1 is red 1 is yellowish and 1 is goldish
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47 views
How does the power station compensates for the current that flows down to earth due to domestic body-current faults?
I know current flows in a loop and energy is used to move it in a loop. Now suppose we get a single phase AC (220/120V) electricity supply for our home and we have earth connection to prevent shocks ...
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52 views
Simulate Automotive Speedometer Sender
I am working on a project and I have run into a little bit of a problem. I have a speedometer gauge that I am trying to send a signal to on a bench (out of car).
The way in wich the it works is ...
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1answer
71 views
Gounding for EMI and signal integrity - LED Matrix multiboard design
I would like to implement a LED Matrix circuit like this one, where the LED matrix enclosed within the blue dots will be on a seperate PCB than the rest of the circuit.
Since this will be a ...
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3answers
567 views
RS 485 ground signal and chassis
I have a shielded twisted pair running from one device polling several devices in an RS 485 loop. The conditions:
The devices are in parallel as they should be.
The termination resistors are in ...
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2answers
443 views
long current return path in star topology of grounding?
I'm designing a system with a MCU board and multiple peripheral boards. I chose a star topology for grounding, in other words, the GND pins in each board is connected to the power source.
However, ...
