Author Topic: How to test if I am grounded properly to work with electronics?  (Read 4952 times)

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Offline tooki

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Re: How to test if I am grounded properly to work with electronics?
« Reply #25 on: March 22, 2023, 07:10:54 am »
I meant that money wise. I don't care if a 2$ proto board gets damaged due to ESD. Sure it can be a pain in the ass to figure out why it is not working properly
There’s a great saying that you should value your time off at twice the hourly rate of your wages.

but just like Terry Bites, in the ~40 years of playing and working with electronics, I can't recall something failing on me due to ESD.
That you know of. “I don’t recall having caused ESD damage” ≠ “there was no ESD damage”.

It’s literally the point of ESD precautions: because a) it’s usually too small to be detected by human senses, and b) the effects may not manifest until much later, it’s essentially impossible to associate a failure to a specific ESD event, so the only protection is to take proper precautions.
 
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Online Siwastaja

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Re: How to test if I am grounded properly to work with electronics?
« Reply #26 on: March 22, 2023, 07:59:03 am »
I meant that money wise. I don't care if a 2$ proto board gets damaged due to ESD. Sure it can be a pain in the ass to figure out why it is not working properly

That time could be spent so much better. The issue with ESD damage is this: it comes in totally unexpected ways. It's not that your $10 devboard just dies and you get a new one. Instead, for example, a microcontroller might work perfectly for a week, and out of blue some ADC reference voltage or brown-out detector limit shifts by 0.5V and now you are getting spurious resets in interaction of your code. Then you can waste days wondering what's wrong with your code, and as a beginner, you haven't figured out effective ways of doing that (say, revision control system + binary search of changes).

This randomness of problems is why you can see people make comments like this: "I can't recall something failing on me due to ESD". This is logically obvious, because knowing something failed due to ESD requires sophisticated lab with equipment like electron microscope. Not going to happen anywhere else except component manufacturers if you are buying in millions and have problems and get the manufacturer to investigate. Instead, we all have random problems that remain mystery.

For same reason, avoid counterfeit eBay/Aliexpress components, try to follow datasheet advice on bypass caps etc. These are surprising time wasters, and as a beginner, mistakes where you can see the cause and effect are good for learning, but totally random-looking problems are not.

The silver lining is, decent level of ESD protection can be had easily. Grounded ESD mat is excellent, but if you can't afford it (~$20), just remove that fluffy carpet from your lab floor and make it a habit to touch some grounded metal (e.g., oscillosscope BNC posts) when you sit down to work, and every now and then.
« Last Edit: March 22, 2023, 09:30:01 am by Siwastaja »
 
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Offline m k

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Re: How to test if I am grounded properly to work with electronics?
« Reply #27 on: March 22, 2023, 10:46:14 am »
One may wonder what kind of a time periods are those every now and then, forget it, you will know.
In my case it's something where last touch is longer than just a moment ago.
It's also automatic, movement stops and you feel a need to touch the frame.
You know you are there when your movement stops before picking something secondary, like a resistor maybe or a heat sink.
I remember feeling uncomfortable if my wrist wrap was not connected to storage frame before taking something out, be that a sticker or a screw, in a pink bag of course.

Some other habits are also still present.
I'm grabbing computer add-on cards from the back plate and put them component side down.

New people will also look a bit differently when I first grab their wrist and only after that the module they are carrying.
Or tell them to put it down on those papers component side down and then lift it from diagonal corners with finger tips, after slapping some assumed ground potential.
Living in a schuko world has at least one positive aspect, naked ground connections.
Advance-Aneng-Appa-AVO-Data Tech-Fluke-General Radio-H. W. Sullivan-Heathkit-HP-Kaise-Kyoritsu-Leeds & Northrup-Mastech-REO-Simpson-Sinclair-Tektronix-Triplett-YFE
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Offline Ground_Loop

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Re: How to test if I am grounded properly to work with electronics?
« Reply #28 on: March 22, 2023, 12:18:09 pm »
I meant that money wise. I don't care if a 2$ proto board gets damaged due to ESD. Sure it can be a pain in the ass to figure out why it is not working properly
There’s a great saying that you should value your time off at twice the hourly rate of your wages.

but just like Terry Bites, in the ~40 years of playing and working with electronics, I can't recall something failing on me due to ESD.
That you know of. “I don’t recall having caused ESD damage” ≠ “there was no ESD damage”.

It’s literally the point of ESD precautions: because a) it’s usually too small to be detected by human senses, and b) the effects may not manifest until much later, it’s essentially impossible to associate a failure to a specific ESD event, so the only protection is to take proper precautions.

So if no one can be sure an ESD related failure occurred how do we know precautions must be taken.  I run into a similar situation with industrial power systems and harmonics mitigation.  No where in the history of earth or electricity can anyone point to a device failure as being caused by harmonics.  Yet I need to install $1M in filtering equipment to reduce harmonics below an arbitrarily decided limit set by IEEE who in there own standards never claim that a failure will occur or provide any evidence of one, but use words like 'may affect' equipment.  It's all about risk tolerance.
« Last Edit: March 22, 2023, 01:25:28 pm by Ground_Loop »
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Offline AndyC_772

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Re: How to test if I am grounded properly to work with electronics?
« Reply #29 on: March 22, 2023, 12:35:59 pm »
So if no one can be sure an ESD related failure occurred how do we know precautions must be taken

https://www.bondline.co.uk/esd-training

Offline tooki

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Re: How to test if I am grounded properly to work with electronics?
« Reply #30 on: March 22, 2023, 03:55:33 pm »
So if no one can be sure an ESD related failure occurred how do we know precautions must be taken.
Well, you and I can’t be sure of a particular incident or failure. Semiconductor manufacturers certainly can, since they have scanning electron microscopes and proper decapping facilities and whatever else is needed to actually find ESD damage. You can see examples in the links I provided earlier.

The problem is that individual people don’t make the association because they did not sense any discharge at any point. That doesn’t mean the discharge didn’t happen.

The point is, basic ESD protection is easy to do, so there’s really no excuse not to.
 

Online Siwastaja

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Re: How to test if I am grounded properly to work with electronics?
« Reply #31 on: March 22, 2023, 06:47:34 pm »
So if no one can be sure an ESD related failure occurred how do we know precautions must be taken.

What a ridiculous strawman argument. Of course some people know - manufacturers and scientists who have researched ESD. This does not mean a beginner should be wasting decades of their time and tens of millions of USD in budget to replicate research in ESD. Instead, they should be spending single-digit dollars and minutes of their time by implementing known-good practices which are result of the research done by others. This is how we collaborate as a species; that's how we can have all the nice things (such as opportunity to create interesting hobby devices with least amount of distractions).
 
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Offline SoulReaver009Topic starter

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Re: How to test if I am grounded properly to work with electronics?
« Reply #32 on: March 27, 2023, 05:32:47 pm »
Thank youi so much for the warning about messing with the sockets.  i saw some youtube videos and did something stupid, luckily nothing happened, but i will avoid any high voltage/amp in the future. low voltage/amp is the same the experience, without the dire consequences. i will stick to that until i have more experience/knowledge.
 

Offline SoulReaver009Topic starter

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Re: How to test if I am grounded properly to work with electronics?
« Reply #33 on: March 27, 2023, 05:37:15 pm »
My brother, mentioned that i could take a copper wire and wrap it around my coax cable. We have a coax cable feed into my room that plugs into our main Ethernet/wifi router/station.

Here is a pic of what i did. will this ground me?

The alligator clip is going to my ESD anti-static wrist strap. I tried to measure continuity from the copper wire to the metal piece which contacts my skin, but there was no continuity measured from my DMM. Weirdly enough, there was no continuity from the alligator clip to the metal contact either. So i guess that is normal. My Ohm resistance measured 0.994 MegaOhms from the copper wire to the metal skin contact plate on my ESD strap.

Thank you for reading and thank you all for replying. I'm very cautious. Probably overly cautious, but good habits are developed early. So I'm trying to adopt these habits now.
 

Offline helius

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Re: How to test if I am grounded properly to work with electronics?
« Reply #34 on: March 27, 2023, 05:50:23 pm »
I will go out on a limb and suggest that, if you live in a developed country, you should be able to have a reliable earth connection in your lab without too much trouble or expense. If your building was wired more than 80 years ago with cap-and-tube wiring, and therefore has no protective earth wiring to the power point, you could consider upgrading it for fire safety reasons as well as the availability of ESD grounding.
 
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Offline AndyC_772

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Re: How to test if I am grounded properly to work with electronics?
« Reply #35 on: March 27, 2023, 07:36:14 pm »
Bear in mind, the important thing with ESD is not that everything "is grounded". What's important is that everything - you, the bench, the packaging for your components and so on - are all at the *same* potential as each other.

You could have a perfectly functional ESD lab in which the flooring, bench mats, wrist straps etc were all connected to each other, but not to any point arbitrarily labelled "earth", or to any other point.
 
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Offline SoulReaver009Topic starter

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Re: How to test if I am grounded properly to work with electronics?
« Reply #36 on: March 27, 2023, 09:03:44 pm »
I dont know what that means lol.  im really new to this.  I live in CA, dont know how old my house is, but we have 3 prong sockets (hot, neutral, and ground).  How do i get a reliable earth connection? and how do i ground myself with that?

i talked to my brother about a ground plug, that plugs into a socket.  He said not to trust one of those (100%) as the ground in those is very close to the hot and neutral, and any imperfections in the wire could result in dire consequences.  I am in the process of making a ground spike, and tying it into my room, but I probably wont be able to do that until a few weeks.  So, I am looking for a method to ground myself in the mean time.
 

Offline SoulReaver009Topic starter

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Re: How to test if I am grounded properly to work with electronics?
« Reply #37 on: March 27, 2023, 09:06:25 pm »
How would i accomplish this?  I hear a lot of people say that and i have no clue what it means.  I havent been experimenting with anything or my kits, yet, as i still dont even know how to ground myself and my stuff properly.

I am getting a rework station tomorrow.  Other users have suggested alligator clipping everything to the station (my ESD strap, my mat, and such).  Will this work?
 

Offline SoulReaver009Topic starter

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Re: How to test if I am grounded properly to work with electronics?
« Reply #38 on: March 27, 2023, 09:10:30 pm »
I am trying to read all the posts, but some of them use terms I do not know. Or give advice that requires other prior knowledge (which i am lacking in lol).  I am watching yt videos on this, and trying to research terms and electrical processes.  I just watched 2 15m videos the other day tha explained how hot, neutral, and ground gets wired through your house, as well as how the current flows through your house.  and the difference between AC/DC.  Very informative, but I am still not sure how to simply ground myself in my carpeted room.  lol
 

Offline Shock

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Re: How to test if I am grounded properly to work with electronics?
« Reply #39 on: March 29, 2023, 08:51:56 am »
Very informative, but I am still not sure how to simply ground myself in my carpeted room.  lol

ESD wrist strap connected to a bond plug, then that gets plugged into the mains outlet.

It will connect the ESD strap to the earth/ground wiring of your house mains. If you are unsure you can purchase an outlet tester. If any of this is unclear ask an adult or get an electrician in.

Don't mess around making another grounding rod, you have no idea what you are doing. Many households now have earth leakage detection and you can circumvent this and also put yourself at additional risk..
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Offline m k

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Re: How to test if I am grounded properly to work with electronics?
« Reply #40 on: March 29, 2023, 10:47:32 am »
You could have a perfectly functional ESD lab in which the flooring, bench mats, wrist straps etc were all connected to each other, but not to any point arbitrarily labelled "earth", or to any other point.

Yes but I would be uncomfortable.

Dry room with floor heating and 0-class round two prong wall sockets.
Forget the neutral, it's there but forget it.
Advance-Aneng-Appa-AVO-Data Tech-Fluke-General Radio-H. W. Sullivan-Heathkit-HP-Kaise-Kyoritsu-Leeds & Northrup-Mastech-REO-Simpson-Sinclair-Tektronix-Triplett-YFE
(plus lesser brands from the work shop of the world)
 

Online Siwastaja

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Re: How to test if I am grounded properly to work with electronics?
« Reply #41 on: March 29, 2023, 03:15:11 pm »
I dont know what that means lol.  im really new to this.  I live in CA, dont know how old my house is, but we have 3 prong sockets (hot, neutral, and ground).  How do i get a reliable earth connection? and how do i ground myself with that?

Easy - just connect your ESD mat to the protective earth - what you call Ground. Through a 1 Mohm (megaohm) resistor to prevent things you are working with from short-circuiting through the straps/mats etc.

Before someone chimes in to say it's dangerous, remember that metal-cased appliances all connect their exposed parts directly to this "ground". It's the whole point of safety earthing. So doing this is perfectly normal, and safe.

Now where I live (Schuko sockets, https://cdn.productimages.abb.com/9IBA202718_720x540.jpg ) we have this earth connection directly accessible, making it easy to just put a crocodile clip there, but I realize in the US 3-prong socket the ground is actually a hole, so you need to plug something into that hole, basically get a plug for the job. Needless to say, this must go 100% absolutely correct so that you don't accidentally plug the ESD mat into line or neutral, which are considered live.

Note that an oscillosscope for example has its BNC posts already grounded through that 3rd prong, so you can always just touch those posts to ground yourself. As oscillosscopes usually come with a separate earthing post on the front (next to the compensation signal generator metal thing), it would be trivial to connect your ESD mat there. Problem solved.
« Last Edit: March 29, 2023, 03:26:01 pm by Siwastaja »
 

Offline Jester

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Re: How to test if I am grounded properly to work with electronics?
« Reply #42 on: March 29, 2023, 10:15:08 pm »
 

Online agehall

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Re: How to test if I am grounded properly to work with electronics?
« Reply #43 on: March 30, 2023, 04:49:33 am »
For hobbyist, I’d say it is much more important to do the basics to not become statically charged than to try to dissipate charge with ESD equipment. (Sure, an ESD mat is always nice though).
I have hardwood floor in my office and rarely wear socks or anything else on my feet when working with electronics. I also avoid all kinds of fleece etc that generate static electricity.

For hobbyist work, this will be enough 99% of the time. Doesn’t cut it for a professional environment though.
 

Offline tooki

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Re: How to test if I am grounded properly to work with electronics?
« Reply #44 on: March 30, 2023, 06:55:41 am »
For hobbyist, I’d say it is much more important to do the basics to not become statically charged than to try to dissipate charge with ESD equipment. (Sure, an ESD mat is always nice though).
I have hardwood floor in my office and rarely wear socks or anything else on my feet when working with electronics. I also avoid all kinds of fleece etc that generate static electricity.

For hobbyist work, this will be enough 99% of the time. Doesn’t cut it for a professional environment though.
I very much disagree. The problem with ESD is that you can’t feel it. So you don’t know whether your measures have actually succeeded in reducing ESD risk. (By the time a static discharge becomes something we can detect with our body, we are far beyond the charges needed to damage parts.)

And as I said above:
A sensitive part can’t tell that you’re a hobbyist and become more forgiving. A damaged part is equally damaged whether you’re a company or hobbyist. Just because you’re your own customer doesn’t mean you’re any happier about a failed or compromised part.

If basic ESD measures were super expensive, I’d understand not doing them as a hobbyist. But given how cheap an ESD mat is, I just don’t see why you wouldn’t do it. And it protects your bench, too.
 

Offline AndyC_772

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Re: How to test if I am grounded properly to work with electronics?
« Reply #45 on: March 30, 2023, 07:07:04 am »
Yes but I would be uncomfortable.

Why?

Uncomfortable about some residual risk to the equipment? Or to yourself?

Bear in mind that the thing an ESD event and an electric shock have in common is that they require current to flow between two points that are at a different potential.

If everything is connected together, and therefore at the same potential, no current flows when they come into contact.

Offline AndyC_772

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Re: How to test if I am grounded properly to work with electronics?
« Reply #46 on: March 30, 2023, 07:15:51 am »
Most of the people don't know about grounding while testing electronic components properly. To make this easier I have made a guide for DIYers.

Sorry, no, this is a poor quality resource riddled with errors and bad advice.

For example:

Quote
Now set the multimeter to diode mode and connect the positive lead of the multimeter to the gate terminal and the negative lead to the source terminal. The gate to source should have zero voltage.

No, it shouldn't. The gate is insulated from the channel, no current flows, and a multimeter in diode mode will show 'O/C' or a similar indication - not 0V.

If the meter reads zero voltage, then the gate is shorted to the source which is a common failure mode in MOSFETs that have been damaged.

Online Siwastaja

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Re: How to test if I am grounded properly to work with electronics?
« Reply #47 on: March 30, 2023, 07:44:30 am »
You clicked a random spambot's link (they got what they wanted) and are now replying to the spambot.
 

Offline AndyC_772

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Re: How to test if I am grounded properly to work with electronics?
« Reply #48 on: March 30, 2023, 08:13:07 am »
Yes, but my comment is primarily for the benefit of any other people reading who may not realise that the content of that site is poor.

Online Siwastaja

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Re: How to test if I am grounded properly to work with electronics?
« Reply #49 on: March 30, 2023, 08:13:42 am »
Expect the message to disappear as soon as moderators wake up. (edit: I have obviously already reported it.)
« Last Edit: March 30, 2023, 08:24:09 am by Siwastaja »
 


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