Questions tagged [groundloops]

Current flowing between two distinct references which are assumed to be at the same voltage, but in fact are not; typically this current flows through unexpected or undesired paths

Filter by
Sorted by
Tagged with
1
vote
1answer
49 views

why does my USB 5V power supply not need a mains ground?

Every small 5VDC power supply (wall wart style) I see has the standard 2-prong Europlug, i.e. no ground. Even those with a British 3-prong plug just use a plastic prong for ground. Background - I am ...
0
votes
2answers
34 views

Probing an externally powered circuit using MSP432 connected to the PC

I have an circuit powered by an external SMPS and I'd like to debug it using a TI MSP432 MCU. The MCU is connected to the PC and I'll use TExaS Display software (it basically works as a cheap low-...
1
vote
0answers
36 views

isolated Ground

I have a question regarding the ground connection of two isolated DC-DC converters. Is the connection advisable considering ground loops? Does it affect the safety? It is about the circuit seen below. ...
1
vote
0answers
41 views

Improving Stereo PCB Design

I just made my first attempt at making a Bluetooth Stereo PCB, and it was okay. This is a Class D Audio Amplifier, with the main IC being the TPA3122D2. O was planning on powering it through USB C, ...
0
votes
0answers
39 views

Determine ground Loop

I have designed a board that is acting weird when you touch the touch screen, turn on and off relays, and even if you touch any wire specify ground(on jacket of wire). I want to know how can I ...
-1
votes
1answer
87 views

Is an inductor in a necessary ground loop useful for limiting noise in ground loops?

I am looking to ground several devices together that all ground to a common PC, and want to at least eliminate any HF noise between the grounds. It occurs to me an appropriately sized inductor series ...
5
votes
3answers
126 views

What is the exact definition of a ground loop? Does a ground loop always have planet Earth in series?

I'm confused as to the exact definition of ground loops. It seems to me that there will ALWAYS be a ground loop if you have: 2 devices (both grounded). a data cable between them. You now have a loop ...
5
votes
7answers
264 views

Frame grounding, data & power - EMI

I'm looking into building some large robotics with (ofcourse) a frame, (shielded) data/communication cables - EtherCAT, and power lines. Now different 'experts', websites and people say all different ...
0
votes
0answers
22 views

How can a ground loop cause a OSD to flicker / dissapear without affecting the rest of the video?

I don't know if it is best to ask this question here, or on drones.stackexchange.com, but I think that I am more likely to get a good answer here even if i might have to provide a bit more background. ...
1
vote
2answers
136 views

Optocoupler to switch 24V using Arduino

I am currently redesigning a circuit to switch a spring applied brake using an Arduino Micro. The current circuit looks like this (please excuse if I'm using wrong symbols, I'm learning by myself): ...
7
votes
2answers
198 views

Ground loops in a PCB with large hole in the middle

I'm designing a board for a client with some unusual constraints. My question is well illustrated with the following simplified example. Assume the positions of everything are fixed. Let's also ...
1
vote
4answers
127 views

Why does this connection not become a low impedance between Positive (Isolated system) and Ground (Earth)?

I was going through a lecture regarding oscilloscope grounding methods and saw this image. Assume I have the isolated widget powered by an external battery. Now, I am going to measure the signals ...
0
votes
0answers
28 views

Headphones wiring issue jack (ground loop?)

I replaced my 3.5mm jack 4 pole but it had 5 wires shown in the image below. I connected the mic ground and stereo sound ground and soldered together in the same slot on the 3.5mm jack. BUT my friends ...
2
votes
0answers
55 views

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 ...
0
votes
0answers
36 views

Ground loop problem

I have two PCB : #1 and #2. #1 is receiving DC supply. #1 routes the DC supply to #2 with two wires (+5V and GND). There is an (non differential) analogic signal which must go from #2 to #1 with ...
2
votes
2answers
88 views

Trace Inductance when routing power nets for PCB

I have a situation where I have Analog and digital grounds. In the picture below the white traces are AGND and the Green DGND. The grounds split where the external supply contacts the board. I am ...
1
vote
1answer
65 views

How to share a digital signal between circuits?

Please see this : The Task I'm trying to create a single module which can safely share a single digital signal. The idea is that each (identical) module can monitor the status of the signal, and can ...
0
votes
1answer
37 views

Connecting sensor and avoiding ground loop

I want to monitor the output from a motor encoder inside a machine, but I am worried about blowing up my Arduino. Can I connect the outputs from the encoder directly to the input pins of the Arduino ?...
0
votes
2answers
26 views

Noise caused by the separate power supply of the sensor?

For my experiment I built a circuit to record long-term vibration data. It consists of two types of sensors (proximity revolution and MEMS acceleration), Arduino, Raspberry Pi and power supplies, ...
0
votes
1answer
46 views

What are the types of devices that should use analog ground?

As the title says, what are the components that require a separation from the digital ground? For example, currently, I have a PCB where the microcontroller is powered and grounded to analog ground ...
2
votes
1answer
169 views

Protection and termination of an outdoor underground Ethernet cable

I have quite a quite long outdoor FTP Cat 5e Ethernet cable (just shorter than 90 meters) that will be used to connect 2 buildings, buried 1 meter underground. As I understand, for a proper operation ...
0
votes
2answers
41 views

How do I remove electrical interference when using same source power?

I have a microphone receiver and a raspberry pi. I'm trying to power them using one DC jack. The receiver uses 12v and the PI uses 5v. The PI is outputting music which goes into an IN port on the ...
2
votes
0answers
76 views

STM32F103 random reboots

we have made a 2 layer board for a STM32f103, and apparently it works fine but we get a random resets now and then. When that occurs there is a 1 in the Bit 27 PORRSTF: POR/PDR reset flag and Bit 26 ...
2
votes
1answer
50 views

Low Side Current Sensing Grounding Question

I recently made a low side current sense circuit to test a power supply. It works well, but I am trying to understand the strange behavior that happens when I apply the negative lead of my probe to ...
0
votes
0answers
51 views

Intercepting signals from vintage computer (common ground)

I am trying to reverse engineer the signalling for a peripheral to an old 4-bit computer and eventually I want to emulate the peripheral and send the appropriate signals back to the computer. I know ...
2
votes
1answer
74 views

Help explaining negative (ground) power connection through TV setup even though wire not connected?

After attempting to use a power inserted for the OTA antenna I discovered an unexpected problem. The inserter is powered by an UnGrounded Ac/DC adapter (Wal-wart as they are often called). All worked ...
1
vote
0answers
90 views

I need help with making a ground loop noise isolator

I want to build a ground loop noise noise isolator for 3.5 mm audio jack. After some research online I found multiple circuit diagrams centered around using audio 1:1 transformers to isolate each ...
1
vote
3answers
146 views

Eliminating an earth / ground loop in an A/V set-up

I have an A/V system with two active sub-woofers. One is close to the amplifier connected with a 1m RCA cable. Its mains connection is into the same power strip as the amplifier. There will be an ...
1
vote
1answer
79 views

Will this design cause corrosion from a ground loop?

simulate this circuit – Schematic created using CircuitLab The design is an undersea light. The connector provides the customer ground-line-neutral. The line and neutral are connected to an ...
0
votes
1answer
76 views

Observe if terminals on a PCB became connected. Know nothing about the PCB, except it is powered with the same power supply transformer

I have a PCB with terminals I have access to, otherwise it's an unknown. I want to observe with my microcontroller (uC) if they become (dis)connected. The PCB is powered by a 24 VAC transformer, the ...
1
vote
1answer
103 views

Buck Converter PCB Planes

I have a question about PCB copper planes with buck converters. For reference, I'm using the LM2673/LM2679. The parts are identical in layout, utilizing the DDPAK/TO-263-7 with the PCB tab being ...
0
votes
0answers
52 views

Isolated step-down module for powering a Raspberry Pi from a speaker's 12V supply avoiding ground loop and interference

I have an older speaker with an iPod dock that I would like to extend with a Raspberry Pi as a streaming music player. At first, I tried powering the RPi from the dock connector with a Micro USB ...
0
votes
3answers
72 views

Short between GND of Arduino and AC powered circuit

Upper left corner is a simple AC powered circuit that can supply 15mA of DC current. Lower left is an Arduino connected via USB to desktop computer. The meter shows a voltage of 1.58V between the ...
1
vote
2answers
94 views

Avoiding ground loops with common-ground DAQ

I am looking to acquire data from several sensors on a machine, each of which are part of a control system featuring several grounds linked at a single central point. I need each sensor's signal at ...
0
votes
1answer
42 views

Analog sensor signal isolation for ADC/DAQ

I am looking for the simplest way of sampling an analog sensor signal in an existing system while avoiding ground loops (say 20kHz maximum frequency). The sensor is a 5V supply with 0-5V return signal....
0
votes
1answer
51 views

Should I use a differential mode amplifier for mixing up to four stereo signals together?

I'm designing (probably over-designing, but I want the experience) a four-input, four-output, stereo mixing setup for my PC setup, but I'm concerned that just tying all the ground lines from that many ...
1
vote
0answers
172 views

Can I connect a PSU to the Ramps 1.6+ and the USB to Arduino at the same time?

I just want to connect the Ramps to the power supply unit and upload the Marlin firmware to the Arduino. I found three possible outcomes 1. Problem I found one person here who says that we should ...
0
votes
1answer
30 views

Timebase Ground-Loops - why place the isolation transformer at the input instead of the output?

In the course of investigating the construction of a home-made 10 MHz lab frequency reference I wondered if the output from such a reference should be isolated. I came across a small article about ...
1
vote
1answer
45 views

Reading UART from device that has floating ground

I am powering an ESP32 over a less-than-ideal power line, that has 4 Ohms of resistance. In order for 5V to arrive at the device, I apply 7V to the power line, such that when 250mA of current are ...
2
votes
1answer
77 views

Is it OK to have a connection between 0 and PE on a DC device?

I have a device meant to be used inside electrical cabinets. It has a metal casing and is powered by 24V DC. It has three power connectors: 24V, 0V and PE. I was surprised to find out that 0V and PE ...
0
votes
1answer
56 views

How to measure isolation resistance between floating ground levels?

There a two isolated ground pins on an isolated dc-dc converter . What method is used for measuring isolation resistance between input side ground level and floating (output side) ground level?
1
vote
1answer
374 views

Shielded Ethernet Cables in Office Buildings - Ground Loops?

I have a question related to shielding and grounding of ethernet cabling in industrial environments, offices and datacentres. What I assumed as correct so far (please correct me if I’m wrong): In ...
2
votes
2answers
114 views

Avoiding ground loops with multiple coax cables

I have to connect two devices with multiple coax cables each carring a signal that has frequency components ranging from DC to a few GHz. I don't know how to avoid ground loops with this type of ...
2
votes
5answers
488 views

Waves on raspberrypi camera feed, Ground loops? electrical interference?

I run a video recorder in a vehicle built on Jetson Nano (Very Similar to raspberry pi). It runs on 5V . The vehicle has a 24V power supply. I power the video recorder with an automotive-grade 24V to ...
1
vote
1answer
222 views

Ground loop problem in op amp circuit

I am having problem with a few millivolts of ground loop in my single channel amplifier circuit when I ground the input (pin 1 on socket, - input of op amp). I am using INA121 instrumentation ...
1
vote
1answer
253 views

AGND and GND - Grounding in Schematics

I have seen a few electrical schematics where there are separate symbols for grounds. "Agnd" and "Gnd" Can someone help me understand what are the differences between those two and where to use "Agnd"...
1
vote
0answers
72 views

Voltage spikes caused by stray wire

I recently had a PCB designed which has several analog, digital, and power elements. The board is powered by 24Vdc which is stepped down using an LDO to 3.3V and 5V. These voltages are used to power ...
1
vote
0answers
535 views

Confusion about GND and PGND

In a digital circuit like a cell phone. If a switching ic has it’s reference point as PGND, separate from the main GND (4v Main vcc coming from battery), but they’re tied together, then What exactly ...
0
votes
2answers
127 views

Ground loop- Why would current flow between 2 earth grounds when signal return path offers the least impedance?

Lets say I have 2 ICs- C1 and C2 acting as driver and receiver for the digital signal. The signal is transmitted through a conductor/cable ( 2 wires) as shown below. I have 2 doubts 1. What would be ...
1
vote
1answer
276 views

pcb board to board connector dealing with ground current

Recently I am designing 2 separate pcb. one of them will be controller with low current signal paths and the other one will have mosfets to control high currents(about 10A). I am thinking of ...

1
2 3 4 5