Problems related to the connection of circuits to ground or earth references. Can affect safety, accuracy, reliability and interfacing.

learn more… | top users | synonyms

0
votes
1answer
34 views

Grounds on an Evaluation Board

For testing purposes, is it ok to assume that every ground pin on the EV board is the same? even if not connected to each other explicitly? i.e. when using measurement probes is it ok to stick the ...
0
votes
0answers
33 views

Sense continuity in cable and lock with MCU

I'm building a "smart" cable lock system where the user will put a steel fitting attached to the end of a steel cable into a lock aperture, after which the presence of the steel fitting needs to be ...
0
votes
0answers
12 views

how to hardwire a car.(dashcam) [migrated]

video where i check all my fuses: https://www.youtube.com/watch?v=74YimFvXEsQ fuses that lighted up without key: 11 Moonroof (20a) 12 accessory power socket (with idk why it did since it doesnt ...
0
votes
1answer
58 views

Should ground be shared between MOSFET gate, draing and source?

I'd like make a voltage buffer with MOSFET STD12NF06L-1 IPAK - STMicroelectronics Configuration of Gate and ...
0
votes
0answers
21 views

Connecting signal and amplifier grounds

I am building an amplifier for my radio. They will both operate from the same battery pack, but will be around 10 meters apart from each other. The output from the radio will be connected to the input ...
0
votes
0answers
43 views

Do I need to insulate the inner box?

I am currently putting a transfotmer inside a metallic case. The transformer has to be grounded so does the metallic case. Looking inside the box, my frnd suggested that I might need to put a ...
0
votes
1answer
51 views

AC->DC Power supply ground and probing

I'm learning electronics and I have an old C64 power supply which was made at our local electrical shop back in the 80s. I'm taking a look at it to try and understand how it works. What I don't ...
0
votes
0answers
13 views

Mixing High Resistance Grounding and Solid Grounding Systems

I recently visited a plant that utilizes a HRG system but the backup generator uses a solid ground system. The plant is experiencing a high amount of equipment failures of VFDs, Communication cards ...
0
votes
1answer
67 views

Can 0V from an isolated source arc to earth ground?

I have a high voltage bus bar (~300-400VDC) that is powered by a variac. This sits in a case that has other electronics that are powered by a step down transformer (120VAC to 24VAC, then rectified to ...
1
vote
2answers
110 views

DO we have to ground transformer?

I am using the transformer (a ballast), and its specfication sheet could be found here ballast specification. But on the data sheet, it doesn't says where we need to ground it. Usually, we would ...
0
votes
1answer
63 views

Different types of grounding [duplicate]

Can somebody briefly explain the different types of grounding with examples? Chassis ground Earth ground Signal ground
0
votes
1answer
40 views

Connect ground of system A to 1v6 of system B?

I have an embedded system powered by a 3.7V LiPo battery that will be connected to an iPod's headphone out cable. The embedded system will perform some DSP on the iPod's audio out signal and use ...
0
votes
2answers
89 views

unbalanced audio - shielding and ground loop for 2 ch

I have a 3 conductor wire that are all wrapped in a foil shield with wire conductor, for a total of 4 wires. I am connecting the 3 inside wires to audio left, right, and ground. This is an unbalanced ...
0
votes
2answers
72 views

unexpected power supply behavior

I am using this large 24V power brick (rated for 9.2A) to power a small circuit (an arduino controlling some RGB LED strip, drawing less than 0.5A). If I physically pull the plug out of the wall, the ...
0
votes
1answer
25 views

PWM Return Problem

A controller send pwm signal with 2 wires 1- PWM 2- PWM Return But servo motor has 1 input pin. So is it correct to use servo supply return (28v Gnd)or servo chassis input for controller pwm return ...
2
votes
1answer
93 views

An “operation” game sensor where the stylus is NOT attached to the power source

Edit: The person operating the catheter will be wearing latex gloves. The only human tissue the catheter would touch would be that of the patient. Also, to clear up some confusion about what exactly ...
-1
votes
1answer
72 views

grounding a 220 -> 110 V transformer

i'm in brazil my house has 220V power i have a transformer that converts 220 to 110V it has 2 prong power and 2 prong power out i would like to get the output grounded. I'm hooking up things with 3 ...
4
votes
6answers
2k views

How grounding works to prevent electrical shock

Can someone please explain the how grounding / earthing to prevent a person from getting electrical shock using simple illustration of a faulty electric iron connected to the 240VAC mains? I don't ...
3
votes
2answers
144 views

Should I use a current limiting resistor for pins labeled as NC which should not be left floating?

Playing around with the 23LC512-I/P SPI SRAM chip from Microchip, I found something strange in the datasheet (http://www.microchip.com/mymicrochip/filehandler.aspx?ddocname=en559704); on page 13, ...
0
votes
0answers
33 views

External power source steered by arduino through transitors - voltage differences?

I'm trying to steer rows of leds through arduino and I came into some difficulties. My circuit is inspired by instructable: So I have something similar to this grid of resistors and transistors on ...
0
votes
0answers
49 views

DIY HV Tube Isolation Transformer

I am making a bench top tube power supply from salvaged transformers. I want to make it as safe as possible so I am checking here before the build. The two 120V/20V transformers have electrostatic ...
0
votes
2answers
70 views

Where to connect frame ground

I have to offer a "FG" connection for the product I am designing. The product is isolated in many parts, so, which part of the circuit should i connect the "FG" to? Below is rough scatch of the ...
2
votes
1answer
96 views

Ground impedance monitor circuit design

I'm trying to design a ground impedance monitor. The idea is that the equipment in question needs to disallow operation if the ground wiring is disconnected or the connection is poor quality. This is ...
3
votes
2answers
106 views

Ground Pour in Power Supply PCB

I'm designing and building a linear power supply for my tube headphone amplifier. Considering this should be HiFi, I'm trying to make it as good as it gets within "normal" building costs and without ...
0
votes
2answers
131 views

When does and when doesn't current flow to ground?

I was thinking about when current can and can't flow to ground. I came up with that current will only flow to ground when we have at least two grounds in the circuit, since then we have a complete ...
4
votes
2answers
189 views

Should I ground an aluminum front panel?

I am building a power supply and it will be housed in a plastic case with a fan. I understand the wisdom of grounding a metal case, but in my case (no pun intended) I have an aluminum front panel. ...
0
votes
1answer
76 views

How do physical connection interfaces handle floating voltages

I am sorry if this is a bit of a novice question but I am new to electronics and have come to a problem that I can't quite see an obvious answer for. A while ago I had a bit of a scary encounter when ...
5
votes
3answers
524 views

Does a Connector With Multiple GND Pins Make a GND Loop?

There are some cable standards that have multiple GND pins on the connector proper. A good example of this is the SATA connector (it has 3 of them). In reality, each GND pin has a slightly ...
1
vote
2answers
84 views

Ground island or VCC island under IC

Suppose I have a small (4cmm x 4cmm) 4-layer PCB with standard stack-up of Signal-Vcc-Gnd-Signal. The board is dominated by two QFP-100 (FPGA and uC) on both on top and bottom side of the board with ...
0
votes
1answer
69 views

Where do I connect earth wire?

I'm trying to use this delay timer to control an exhaust fan. I have a 3 pin connection (with earthing wire) powering this fan and it works fine. If I have to insert this delay timer module in ...
4
votes
3answers
372 views

Shall I connect inverter with boat GND?

A friend of mine is building a boat. On this boat, he has 12V batteries with a 230V/13A transformer. Recently somebody suggested he should connect the null with the ground. With DC, this is common ...
0
votes
2answers
90 views

Earth connection missing on electric circuit, getting lots of noise with audio equipment

I have a question today that possibly crosses to another website, but i'm interested in your expertise here. It's more or less about music, but also about noise and electric current. Basically, I ...
2
votes
1answer
63 views

pH sensor project: trouble with RF interference

I built this pH sensor project on a breadboard and I'm having a big problem. The output on the voltmeter is completely erratic, and I'm pretty sure it's due to RF interference. When I connect the ...
8
votes
1answer
631 views

Why is this resistor connected between connector shield and ground?

I was looking over my raspberry pi model B and I noticed a resistor between the USB power connector shield and ground. I've noticed this on many PCB designs with much larger packaged resistors ...
0
votes
0answers
38 views

Dilemma when ground and earthing is used [duplicate]

What are the differences in ground, neutral and earth. I came to a point neutral grounding. Is it differ from earthing? And any difference in representation of all.
9
votes
2answers
659 views

Why are some mounting holes connected to ground?

Why are plated mounting holes connected to ground ? I read that if you are connecting your board to chassis ground, then it should be connected at only one point and connecting say 4 mounting holes ...
2
votes
1answer
118 views

Grounding for car stereo adapter PCB

I've built an audio adapter for car stereo system. It contains microcontroller, a connector to stereo system (a few data pins and line-level audio output), Bluetooth audio module (RN52) and power ...
0
votes
1answer
82 views

Shielding not connected to USB connector causes tablet restarts

I have a custom USB cable, USB type A male on one end and a DB-9 connector on the other end (only using 4 pins). The shielding of the cable is connected to the USB connector but not the DB-9 ...
0
votes
1answer
59 views

Hooking audio compressor to mains without chasis

I am nearing the completion of my DIY compressor project, and I have a rather seemingly basic question.. Once I hook up my toroid and everything, since I don't have my 19" 1U rack enclosure yet, but ...
0
votes
0answers
29 views

high voltage chassis grounding [duplicate]

Suppose a high-voltage transformer has its chassis grounded, is it safe to touch the chassis? What if the HV terminal accidentally touched the chassis at point A @ 10kV, while the grounding is at ...
1
vote
1answer
112 views

high voltage safety [closed]

I remember having seen microwave ovens without the earth connection. My first question is : Is it correct that if you touch the MOT transformer chassis, but leave the other terminal floating in air ...
4
votes
1answer
272 views

Single point vs Ground plane, in audio OP AMP PCB layouts

Recently I had posted a seemingly innocent question on another forum. I was trying to keep a small and relatively simple circuit down to a 2 layer board and was asking about the shielding merits of a ...
0
votes
0answers
46 views

Needed help on earthing grid mat installation

I needed knowledge about earth mat installation for underground metro. I am not sure if a test reference electrode could be used for two earth mats. We have limited space and I want to cut off some ...
11
votes
3answers
1k views

Why is there a 0R resistor linking GND and AGND in analog voltage reference circuit?

This is related to another question I've just posted (What's the purpose of a ferrite bead inductor on a analog voltage reference circuit?), regarding the battery charger described in the AVR450 ...
5
votes
2answers
875 views

PCB design review: Decoupling, bypassing and grounding

I'm trying to make my own wireless sensor using ATmega microcontroller. I've some basic understanding of electronics but I'm a total amateur when it comes to designing circuits and PCBs. This is just ...
0
votes
1answer
70 views

Voltages with an earth ground

In this diagram, from what I understand the voltage between the positive terminal and the first earth ground is \$ 0V \$ and the voltage between the negative terminal and the earth ground is \$ 0V ...
1
vote
1answer
114 views

Compromise needed combining virtual grounds

This is a long story for which I hope my proposed solution to a problem I've created will be a stable one. But op amps can surprise you, so let me explain. The circuit is large and complex, so I'd ...
1
vote
3answers
358 views

Child-Safe setup for ESD protection environment on desk

I need to setup an anti-static workbench in my spare office, and kids sometimes get into it ever since they learned how to pick the locks. My intended approach is to: Lay out an ESD mat on the ...
1
vote
1answer
85 views

From grounding to audio amplifiers

Ultimately I would like to assemble this simple audio amplifier: Given my lack of any significant knowledge in the topic I have several problems and questions. Grounding: In the thread What is ...
1
vote
3answers
195 views

Will standing on a non-conductive surface with wet feet prevent grounding and therefore electrocution?

It is a well known fact that one should not handle electrical equipment in general and electrical home appliances in particular when barefoot, or when one's feet are wet (even when wearing ...