Questions tagged [chassis]
The chassis tag has no usage guidance.
54 questions
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Is this explanation of chassis grounding correct?
In Henry Ott's Electromagnetic Compatibility Engineering, Section 3.2.5: Chassis Grounds explains that circuit ground should be connected to the chassis where the I/O cables come in, as shown:
This ...
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Grounding Lug Straight To Chassis
Connecting some thicker gauge cable to my trailer to ground neutral for the 12v DC system. The current 8AWG wire uses a receptacle style lug where the wires are inserted and the that receptacle is ...
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Cooling fan direction
I am building a temperature controller. The controller is built in a metal rack mount chassis. The components inside the controller generally consist of ACDC power supplies, an arduino and small ...
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To which ground should TVS or ESD diodes connect?
I am designing a circuit with both signal ground and earth. As far as I know, a TVS should be connected to the earth.
What if there is a huge voltage different between the ground and the earth?
Let ...
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Class III appliance with metal chassis connection
I am designing a SELV/Class III appliance (lab/industry type, IEC 61010), supplied via two-pin isolated DC power. For mechanical reasons, the chassis has to be metallic. As a result, there are going ...
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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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Decoupling Positive and Negative to Earth and Chassis Connection Layout
Very stupid question but I need to ask.
I'm doing the following. The two capacitors are supposed to be used for balancing the impedance to a common ground so that the common mode noise can be reduced.
...
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Correct configuration for adding an earth terminal block?
I have a small motor controller test board setup like the diagram below:
A few loads such as a motor controller, and some switches are connected to the live and neutral terminal blocks for power. ...
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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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When to choose Class I vs Class II AC to DC power supply?
Feels like I'm missing something obvious here, but when is it appropriate to use a Class I vs a Class II AC to DC power supply for a commercial electronic device? Should Class II only be used when the ...
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How many "grounds" are there and what is the difference?
I stumbled upon many terms for ground, naturally as newbie I got very confused.
ground earth
chassis ground
earth ground
common ground
signal ground
Are there any more?
I assume some are for AC and ...
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Does USB 2.0 high speed host require a chassis ground?
I'm trying to design a microcontroller-based board in which the MCU will function as a USB 2.0 High Speed (480 Mbit/s) host for connected USB HS devices. I have been researching circuit design for ...
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What are the drawbacks of connecting circuit GND and Chassis via multiple mounting screws (for EMC and Safety)?
Although there are various suggestions around for how to connect circuit GND to the earthed chassis (say, the chassis has a point-to-point resistance of around 1 mΩ) in devices, there seem to be two ...
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When does a PCB require a chassis ground connection?
Do all PCBs require a chassis ground connection point?
I am designing a circuit board which will be used in many different types of assemblies. It is a small mixed-signal, low-voltage (24 VDC power, ...
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Wire gauge to connect to chassis in van
I'm building an AC electrical system for my van conversion and I'd like to know if there's a minimum wire gauge I should use to connect my negative bus bar to my van's chassis.
Specs:
I'm running a ...
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Do automobile DC systems sport a device synonymous to the electrical infrastructure that we call Earth Ground wiring in standard household AC systems?
In automobile DC circuits, the chassis is typically connected to the negative battery terminal and, thus, the chassis provides the infrastructure for closing the DC circuit. In diagrams, this is often ...
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Old Variac -- chassis ground? is it safe?
I've got an old (vintage!) GenRad Variac (below) that has two prong plug and two prong socket. I want to modify it to add a safety earth pin to both input and output. In doing so, I opened it up and ...
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ESD protection to the ground or chassis?
How to add ESD protection diodes to all cables (I/O, positive, ground)(see pink box below). Should I connect them to the chassis or battery negative terminal?
There may be some potential difference in ...
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How is Chassis ground connection implemented for an input cable with TVS diode protection?
I believe my question is different enough in specifics to Is it better to connect ESD (TVS) Diodes to chassis ground or signal ground? to warrant a new question.
According to Electromagnetic ...
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Grounding a chassis with two prong plug
So I kinda shot myself in the foot by purchasing a two prong wall wart to power an audio preamplifier that I designed. I forgot to consider the fact that I should ground my chassis to the earth ...
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Is it better to connect ESD (TVS) Diodes to chassis ground or signal ground?
Application: We have a PCBA inside a vehicle's embedded system. The PCBA receives DC voltages from a power input connector. We do have access to signal ground aka 5V_return at the power connector and ...
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Right way to couple DGND to Chassis ground
So we all know certain things:
DGND (and subsequently AGND) needs to be coupled to Chassis ground, or Earth at one position, at least, in a device.
The Earth is otherwise considered as a hazardous ...
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Connection between Chassis GND and Circuit GND for ESD/transients
All of the images in this post are from Henry Ott's Book, Electromagnetic Compatibility 2009, and I would like some clarification on some things about them.
Figure 14-14 seem to be in conflict with ...
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Plane Chassis Grounding
I'm having a hard time understanding Chassis Grounding. From my understanding, the frame of a plane is used for that and all of it can return to the batterie.
Given my understanding, it remains a ...
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How do you avoid mixing CHASSIS GND and sensor GND when reading a sensor?
So I'm aware that in some systems they have different circuits with different grounds. For example, cars have at least a chassis ground and a sensor ground, and there is a measurable difference ...
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Is there a colour standard for mains 'signal' wiring?
Hello I am currently wiring a mains powered chassis. I have relays which use mains voltage levels for controlling other mains voltage relays. I would like to differentiate between the signals by using ...
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Proper Chassis Grounding
I'm starting to design things that run off mains voltage and I want to be sure that I have a proper connection from my chassis to earth ground.
I've been reading a bit about proper grounding and have ...
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DMX chassis(?) pin?
I want to recreate this circuit (only show a small relevant portion):
And my XLR plug for input (K2) looks like this:
I found a reference how to connect K2, +, - and GND to the correct pins of the ...
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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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does the 24 Vdc supplied circuits with metal chassis needs to be grounded to earth?
I used put some electronic circuits together in a plastic box, with a DC power jack attached to the box for a 24V dc supply to my circuit. Everything works fine. However i now plan to put all the ...
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Chassis punches for IEC C13 sockets?
I can't believe I'm having trouble finding chassis punches for the IEC C13 socket. This has to be the most common way of getting 120VAC into a box, yet I can't find any chassis punches.
How do most ...
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Using Chassis as a conductor for DC Power Supply Return
Is it considered a good practice to use the chassis as a return path to a DC Power Supply?
I have been given a rack mounted device that switches 480 volt power on/off remotely. The remote feature is ...
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DC Power Jack - minus to chassis?
Is it OK to connect the minus from a DC Power supply, 15v 4A (switched) to a metal chassi as ground?
No electronics will be connected to the chassi.
The jacks that I have found seems to be made of ...
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SMPS output grounding (PE)
I am designing an ultralow noise 5V/3A SMPS.
On the DC side, I see the ground (DC) is earthed (chassis ground) using a direct connection 0 ohm or using a Y capacitor. What are the differences between ...
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SMPS chassis ground and earth ground
I'm designing a ultra low noise smps and I have some questions about ground/earth chassis. The main goal is very low noise on DC output.
Earth (PE) should be connected to one point (only) to the ...
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What are these "X"s / crosses on this schematic's wiring? Traces attached to the metal housing (ground)?
Below is a section of the schematic for the RF modulator of a Nintendo NES-001 system. I am curious what these Xs are that I've boxed in red below. Looking at my own NES-001 and matching locations, I ...
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circuit ground vs chassis ground
Can someone briefly explain what's the point of separating circuit ground from chassis ground with a capacitor + resistor?
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What could happen if a lightning strikes a car with a battery connected to the chassis ?
I was wondering today what could possibly happen if a lightning strikes my van where I have a 12V battery negative connected to the chassis. Could that destroy the battery or start a fire?
In order ...
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ESD Protection on Un-grounded Chasis
I am designing a product solution which needs a 240V AC to 12V DC. I am getting that done with one of those standard laptop chargers from a reliable OEM(with necessary certifications) which looks like ...
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Chassis grounding short circuit
if the chassis of a DC power supply is earth grounded , and lets say I am messing around with my power supply and I touch the positive voltage perhaps through a jumper wire or a component on a ...
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If current flows through lowest resistance path, why circuits with grounding still work?
Okay, this may sound stupid.
Current (conventionally) flows from the positive to the negative terminal of a source. This also means that the source's negative terminal is on lower potential than the ...
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Why not connect battery negative to chassis?
I am making a mobile robot with a metallic chassis. Usually, a non-moving appliance will have the ground pin of the wall socket connected to the chassis, but in a moving device, there is only the ...
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What are these kinds of pins called?
What are these connectors at the edge of the chassis called? I thought they were pogo pins, but it seems like they're not uniform and are keyed? How well do these kinds of connectors stand up to ...
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Difference Between - (Minus Sign) and Chassis Ground in Schematics
I was working on building some projects from the book Electronic Projects for Musicians and I noticed that in most of the schematics there are two symbols for what seems to be ground. One is a - (...
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Extra 2 DB9 pins connection
Many DB9 symbols have 2 additional pins other than the 9 signal and GND pins that they are known for. How and to what are these 2 pins connected ? Pins 10 and 11.
Is it connected to chassis ground or ...
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chassis ground and its location wrt common mode currents
This is related to chassis ground.
The chassis ground is connected to the system ground at the entrance of the cable that brings in signals and not at the other extreme or opposite end of the PCB. ...
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Chassis ground on Ethernet RJ45 Connector
In the reference schematic of an Ethernet transceiver, I noticed that the chassis ground is connected to system GND by 1nF/2kV Capacktor(C24). What is the purpose of doing this?
The connector(...
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Basic questions about chassis grounding
I am uncomfortable with the notion of chassis ground but I can't pin down what exactly bugs me. So I'll start with an example and ask a couple of questions on the way. My background is this: I have ...
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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 ...
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Grounding the chassis with capacitor
My question involves chassis grounding to earth ground.
My PCB circuit is a simple signal generator using a microcontroller. It has a separate 'ground' from earth ground, supplied by a floating 5VDC ...
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