All Questions
26 questions
2
votes
2
answers
766
views
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 ...
- 45.6k
1
vote
1
answer
112
views
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 ...
- 88.8k
0
votes
1
answer
242
views
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. ...
CommunityBot
- 1
1
vote
0
answers
111
views
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 ...
- 23.4k
4
votes
2
answers
247
views
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 ...
3
votes
1
answer
898
views
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 ...
- 34.9k
1
vote
0
answers
169
views
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 ...
- 1,097
4
votes
1
answer
1k
views
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 ...
- 23.4k
10
votes
1
answer
3k
views
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 ...
- 11
5
votes
2
answers
7k
views
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 ...
- 1
2
votes
2
answers
598
views
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 ...
- 23.4k
3
votes
1
answer
1k
views
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 ...
- 88.8k
6
votes
2
answers
3k
views
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 ...
- 1,557
4
votes
1
answer
1k
views
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 ...
- 189
0
votes
2
answers
1k
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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 ...
CommunityBot
- 1
1
vote
1
answer
10k
views
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 ...
- 14.6k
6
votes
3
answers
2k
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 ...
0
votes
1
answer
664
views
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 ...
- 369
1
vote
1
answer
2k
views
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 ...
- 17.6k
1
vote
2
answers
5k
views
circuit ground vs chassis ground
Can someone briefly explain what's the point of separating circuit ground from chassis ground with a capacitor + resistor?
- 153
0
votes
1
answer
181
views
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 ...
- 47k
1
vote
1
answer
917
views
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 ...
- 133
0
votes
1
answer
415
views
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 ...
- 134k
11
votes
2
answers
8k
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 ...
- 393
139
votes
6
answers
68k
views
Should chassis ground be attached to digital ground?
I'm working on a PCB that has shielded RJ45 (ethernet), RS232, and USB connectors, and is powered by a 12V AC/DC brick power adapter (I do the 5V and 3.3V step down on board). The entire design is ...
CommunityBot
- 1
10
votes
3
answers
2k
views
What do I do with the extra "ground chassis" tab on a DC power jack?
Product Link
Datasheet
I have about fifteen 9v wall warts within specs for the circuit; I'm going to use the one that fits the jack. There are three solder tabs on the jack. One for the positive tip,...
- 22.9k