Build a safe and cheap ESD workstation [EVERYTHING THERE IS TO KNOW...PROBABLY!]

[Siwastaja]

Almost all modern components (including IC) has built-in ESD protection. And in a most cases these protection is quite enough to allow of handle of these components by bare hands (without any extra ESD protection at all).

This built-in protection is significantly less, though, than required per standards for product qualification. It's only designed to protect the part from handling in usual ESD controlled manufacturing environments, plus a little more for safety margin. If you completely ignore all precautions, risk of one day creating damage which causes weird, hard-to-debug issues is very real. This is why I suggest the bare minimum, grounded ESD mat on which the work is performed. This will be also the single most effective measure.

[TERRA Operative]

I have my desk-sized ESD mat wired directly to the earth screw on the nearest power outlet (Many modern Japanese outlets are the same as USA, but they have a flip-up lid with an earth screw underneath, I have them throughout my house).
Then my wrist strap is connected to one of those black angle brackets with the banana jacks and studs, which is also wired to the same earth screw on the outlet.

This way it is all connected in a star configuration so if something becomes disconnected, it won't 'break the chain'. I have redundancy of a sort between my wrist strap and mat.

[YouCanDoIt]

What are you doing?

If you are handling some specifically sensitive special parts AND doing it in large scale production you want to take ESD really seriously.

Otherwise, I won't suggest ignoring the topic...

Thanks for joining the topic. Well, nothing very serious like the above, but serious enough to understand that handling stuff with bare hands is bad. To the above workstation I also added good quality antistatic gloves and coat. It will not cover everything, but enough.

Getting an actual ESD mat (I didn't know it is so difficult and that fakes exist; I bought mine from batterfly.com and they are fine) is pretty much enough.

Yes, the silicone mat I talked at the beginning is not ESD safe and I would also add that from china should be avoided even the regular ESD mats. If you have read all the topic you will see that the Mat I'm going to buy is one of the best quality, so I'm fine with this.

I also didn't know that "binding posts" can be expensive or people would waste time about pondering which binding post to get.

I live in a country which uses Schuko sockets/plugs which has exposed PE connectors in the socket. I just use an alligator clip to connect to PE. Other end goes to the ESD mat. When working with components and boards, my hands naturally rest on the mat. Job done.

I think I have the same sockets/plugs like yours (although not in every room of the home), Do you recommend to modify my workstation like below? Yes, the yellow plugs (the only god quality ones) are very expensive and can go up to 30€ and more. However, the only reason for which I didn't continued to find for alternative connections is because I found the yellow plug you see in the photo from the same company where I will buy the mat and for around €10. The advantage is portability, easy plug & play and an extra layer of security given by the inside 1MΩ resistor. Do you still recommend to do the modification even in such case?

Almost all modern components (including IC) has built-in ESD protection. And in a most cases these protection is quite enough to allow of handle of these components by bare hands (without any extra ESD protection at all).

This built-in protection is significantly less, though, than required per standards for product qualification. It's only designed to protect the part from handling in usual ESD controlled manufacturing environments, plus a little more for safety margin. If you completely ignore all precautions, risk of one day creating damage which causes weird, hard-to-debug issues is very real. This is why I suggest the bare minimum, grounded ESD mat on which the work is performed. This will be also the single most effective measure.

In addition to what says Siwastaja I would also add that it is the opposite of what you say, is far more of a problem now than it has ever been.
Per the ESD Association:

“The age of electronics brought with it new problems associated with static electricity and electrostatic discharge. And, as electronic devices became faster and smaller, their sensitivity to ESD increased. Today, ESD impacts productivity and product reliability in virtually every aspect of today's electronics environment. Industry experts have estimated average product losses due to static to range [up to] 33%. Others estimate the actual cost of ESD damage to the electronics industry as running into the billions of dollars annually.”

I have my desk-sized ESD mat wired directly to the earth screw on the nearest power outlet (Many modern Japanese outlets are the same as USA, but they have a flip-up lid with an earth screw underneath, I have them throughout my house).
Then my wrist strap is connected to one of those black angle brackets with the banana jacks and studs, which is also wired to the same earth screw on the outlet.

This way it is all connected in a star configuration so if something becomes disconnected, it won't 'break the chain'. I have redundancy of a sort between my wrist strap and mat.

Terra, you're increasing my doubts. In this topic I see that all connections goes to the plug:

Do you recommend to change my workstation like below?

I'm not sure if in this way I will need some extension cable, but are you sure this is good when the ESD mat sold by the company is supposed to be connected through 2 connection points?

Another concern: some users suggested to increase resistance value. While this could be good in terms of safety, I have just noticed here that it could also reduce effectiveness. The above connection will result in 4 MΩ resistance unlike 3 MΩ of my original project. I'm wondering if I should buy the yellow plug which does not have any builtin resistance.

[shabaz]

Hi,

You can follow manufacturer guidelines (posted in an earlier comment) regarding connections.
You're over-thinking this unfortunately with assumptions with no clear reason why you think every connector on the mat has to be used (it doesn't). Just buy the equipment from a reputable seller (TME, Digikey, Conrad, Eleshop etc) and no need to stress out about it, you're spending more time deciding, than the end equipment cost.

A friend required ESD kit last week, we took one look at Amazon, decided we were not sure of anything there, and simply ordered from a specialist supplier ("Somerset Solders" in this case, but there will be decent suppliers in most countries as mentioned) - the cost was still low. Less than 100 euro for the premium quality stuff, anti-allergy etc., inclusive of taxes and shipping, got her everything she currently needed, all is safe with the required resistances with no need for the user to do anything extra, and it is known that it will work for the next decade, since that's almost how long I have owned that particular mat too, and it's still functioning.

Job done, all decided and ordered in 10 minutes, and that's how long it will take to put it all together when it arrives.

[TERRA Operative]

IMO, this is a prime case of paralysis by analysis.

Just get a quality mat, wrist strap and a good grounding point and hook it up.
All my connections go directly to the earth point on the mains socket, the wrist strap via one of those black brackets.

As long as you have everything connected reliably to ground, it'll be fine

[YouCanDoIt]

Hi,
You can follow manufacturer guidelines (posted in an earlier comment) regarding connections.

Hello shabaz, I'm glad to see you again.
This is what I have done (at least I think so). Only difference is the location of the connection points in the mat:

And this is how a continuos monitor similar to mine is connected (basically just like my picture above):


I like much more the solution used by TERRA Operative, one only connection point on the top right:


However, if you look at the constant monitor product page it is clearly stated the following:
*ATTENTION – The mat must already be earthed.

You're right guys, I'm over-thinking, but you see how much is easy to do mistakes. With one only connection as suggested from Terra, both the connections are earthed at the same time by the socket plug. I'm not sure if this will result in some malfunction of the whole system, but there must be a valid reason if the manufacturer stated such warning. We don't want people reading this topic ending up with a wrong connection diagram (especially the ones that add a constant monitor to the system).

[Gyro]

You are, indeed, massively overthinking this. All leads, earthing points etc, have integral safety resistors so the connection 'diagram' isn't particularly relevant - it's not as if you're trying to avoid a low impedance AC ground loop.

Putting it simply.

1. The work surface needs to (ESD) referenced to ground.
2. You want to avoid ESD discharges between the operator, connected via the wrist strap, and the devices sitting on the mat.

That's it. For most people, clipping the wrist strap to a stud on the corner of the mat is most convenient. If you want to go to the added expense of a screwed on bench edge mounted strap connection point, then it makes sense to take it back to the yellow earthing plug rather than bringing it up to the mat. There is no 'right or wrong diagram' as long as '1' and '2' are satisfied.

If you are worried about configuration to this level then you should maybe be considering a floor mat too.

[m k]

I've learned to use a wrist wrap, it's unbeaten when stuff is far apart.
You can also have many of them around places, but there is also a good possibility to forget it, one way or another.

One of the ways is that you forget which wrist it is and so wipe stuff away.
Or have it still disconnected after the last place change.

One other thing I've learned is that all these wires and hoses are mostly always somehow wrongly placed.
Or if nothing else then the light is behind a shade.

[YouCanDoIt]

You are, indeed, massively overthinking this. All leads, earthing points etc, have integral safety resistors so the connection 'diagram' isn't particularly relevant

Does this means that I should buy the earth plug with integrated resistor rather than trying to reduce the total resistance of the the system through an earth plug without any integrated resistor? Connected like this should result in a total of 3MΩ (plug + mat connection cable + wrist wrap).
From this topic:

My real question is if theres a problem with that connection, because the ESD sockets already have 1Mohm and the EU plug have another 1Mohm, that connection will make a 2Mohm resistance. Plus if i use a wrist band with another 1Mohm resistor that result in a final 3Mohm to earth.
Will that decrease the effectiveness? or will be just fine?

As you suspected, there will be a very small reduction in effectiveness due to the higher 3 MΩ resistance to ground, compared to a 1 MΩ resistance.

Can I hope that 3MΩ will not affect effectiveness?

...it's not as if you're trying to avoid a low impedance AC ground loop.

You mean that the warning only applies when trying to avoid a low impedance AC ground loop?
Please note: the one in the photo below is a different brand than mine, but it is pretty much the same. I should receive mine within days and will check if there is the same warning.

That's it. For most people, clipping the wrist strap to a stud on the corner of the mat is most convenient. If you want to go to the added expense of a screwed on bench edge mounted strap connection point, then it makes sense to take it back to the yellow earthing plug rather than bringing it up to the mat. There is no 'right or wrong diagram' as long as '1' and '2' are satisfied.

If you are worried about configuration to this level then you should maybe be considering a floor mat too.

Well, in terms of costs there is no difference between the two method of connections below. The only reason why I prefer the second method is because I have a much larger free area, but in this way I'm going against the warning because constant monitor device and mat are earthed at the same time by the yellow plug. If you are sure I can safely ignore such warning, then I will go with second method otherwise I will fallback to the first one (which is the same of the posted youtube video).

A floor mat is something that I have initially evaluated, but after I saw the need of a second connection to the ankle I said a big NO. After all, I didn't saw such connection even in factories that assembly electronic boards (only ESD workbench, gloves and coats just like me).

[Siwastaja]

Literally the left half of this picture does the job. Added benefit from wrist strap is small, because the range of wrist strap is limited to working within the same table, and when you do that, your hands would periodically touch the mat anyway. It's not like if you lift your hands for 10 seconds you would magically gain a large enough charge to damage anything else but some super weird specialty devices.

You can use 1M series resistor if you so wish. The mat itself is resistive enough to prevent large-current ground loops between your instruments and devices under test, so I don't bother. There is no safety implication either way; every metal frame grounded device you can freely touch is connected to that very same PE, in that very same socket.

[YouCanDoIt]

I've learned to use a wrist wrap, it's unbeaten when stuff is far apart.
You can also have many of them around places, but there is also a good possibility to forget it, one way or another.

One of the ways is that you forget which wrist it is and so wipe stuff away.
Or have it still disconnected after the last place change.

One other thing I've learned is that all these wires and hoses are mostly always somehow wrongly placed.
Or if nothing else then the light is behind a shade.

Thanks for your comment, but I'm not sure I have understood what you want to say. The only reason I see for having multiple wrist straps is a quick replacement in case that one breaks (the wire is very fine and I can already see how it can easily break over the time). Regarding usage, it is supposed to be used only one and worn in the left or right wrist (depending if one is left-handed or not).

[YouCanDoIt]

Siwastaja, many thanks for your suggestion. I think that whether to use a plug or not depends mainly from the user. In my case, for €10 more, I prefer the plug and take advantage of portability and the additional resistor. However, it's good to know that the connection is still possible without plug.

My main problem is the constant monitor integration which I will explain better in my next message.

[YouCanDoIt]

Ok guys, I'm talking with an agent of the ELMA company. First of all let me confirm that the high heat resistance of their mats is real. So, as of now, I would say that their mats are the best especially for soldering.
They suggested me to combine their wrist straps. I didn't found (for my case) any desirable feature or improvement over what already provides the blue one posted at the beginning of the topic, but is durable and pretty cheap and it's always good to have a second wrist strap as spare part.

The main problem I'm facing is the connection with the constant monitor. The company has their own one for which they sent me the connection diagram. It's the same of the one I posted in the YT video, just with a different mark. As seen from the pdf, there is the below bench cord to connect, but my constant monitor doesn't have such connection (just the ground wire):
.
Here the same device is connected without bench cord, but with the statement "*ATTENTION – The mat must already be earthed.". I suspect this has some relation with such cable. I could be wrong, but I interpret this as "The bench cord is not needed, but the mat must already be earthed."
I'm stuck on how I should modify my connection scheme without the bench cord. The company can't help unfortunately.

[tooki]

A floor mat is something that I have initially evaluated, but after I saw the need of a second connection to the ankle I said a big NO. After all, I didn't saw such connection even in factories that assembly electronic boards (only ESD workbench, gloves and coats just like me).

Factories and workshops built for electronics use typically have conductive floors, which are then used in combination with conductive ESD footwear that, together with ESD workbenches, largely eliminate the need for wrist straps, etc.

The ankle straps you’re talking about are probably the foot grounders you can wear to enable the use of ordinary (non-ESD) footwear. If you use proper ESD footwear you do not need that. Note that the strap on a foot grounder doesn’t connect to the mat, it slips in your sock to make contact with you.

[YouCanDoIt]

The ankle straps you’re talking about are probably the foot grounders you can wear to enable the use of ordinary (non-ESD) footwear. If you use proper ESD footwear you do not need that. Note that the strap on a foot grounder doesn’t connect to the mat, it slips in your sock to make contact with you.

Well, this changes everything. It remains to see how much safety provides the addition of a floor mat. I suspect it would be very minimal, but I could be wrong.

A floor mat is something that I have initially evaluated, but after I saw the need of a second connection to the ankle I said a big NO. After all, I didn't saw such connection even in factories that assembly electronic boards (only ESD workbench, gloves and coats just like me).

Factories and workshops built for electronics use typically have conductive floors, which are then used in combination with conductive ESD footwear that, together with ESD workbenches, largely eliminate the need for wrist straps, etc.

I don't think it is like so. A wrist strap is still needed along with all the other stuff and this is clearly showed in all connection diagrams:

[tooki]

The ankle straps you’re talking about are probably the foot grounders you can wear to enable the use of ordinary (non-ESD) footwear. If you use proper ESD footwear you do not need that. Note that the strap on a foot grounder doesn’t connect to the mat, it slips in your sock to make contact with you.

Well, this changes everything. It remains to see how much safety provides the addition of a floor mat. I suspect it would be very minimal, but I could be wrong.

A floor mat is something that I have initially evaluated, but after I saw the need of a second connection to the ankle I said a big NO. After all, I didn't saw such connection even in factories that assembly electronic boards (only ESD workbench, gloves and coats just like me).

Factories and workshops built for electronics use typically have conductive floors, which are then used in combination with conductive ESD footwear that, together with ESD workbenches, largely eliminate the need for wrist straps, etc.

I don't think it is like so. A wrist strap is still needed along with all the other stuff and this is clearly showed in all connection diagrams:

Feel free to think that, but you’d be wrong:

ANSI/ESD S20.20 Paragraph 6.2.2.2 Personnel Grounding Guidance
“ESD protective flooring used with approved footwear, may be used as an alternative to the wrist strap system for standing operations.”
( http://www.esdsystems.com/pdf/0211use.pdf )

FAQ: DOES AN ESD FLOOR DO THE SAME THING AS A WRIST STRAP?
“ESD floors in combination with ESD footwear provide the same connection to ground as a wrist strap. Used properly, ESD flooring provides mobility without the restrictions of tethering.”
( https://staticworx.com/faq/esd-floor-wrist-strap/ )

That is one of the big reasons companies like ESD floors: they work without the user having to remember to connect anything, and continue to work while carrying things, pushing carts around, etc. — the only key is that the footwear, carts, chairs, etc. must all be ESD versions.

Note also that you said you didn’t see ESD mats anywhere. Right. That’s why I said ESD floors — an ESD floor is the entire floor, so it just looks like a normal floor. In fact, you can convert a normal floor simply by applying an ESD coating to it. You may have seen an ESD floor without realizing it. An ESD mat accomplishes the same thing, but only on a limited area. The main reason for ESD mats when used on an already ESD-safe floor, by the way, is to prevent fatigue.

[YouCanDoIt]

You're right, as long as the operator doesn't lift both their feet at the same time and does not seat (in this case a wrist strap is required and I suppose the ESD mat too, the real ones, not the cheap silicon ones as I would like). i think it depends mainly from how an operator feel more comfortable, but I must admit that now I am in doubt. I don't like to stand up and this would require all such expensive stuff which will result in only one (and questionable in terms of percentage) advantage: increased safety. With ESD flooring I still have doubts about the body skin excluded from the system.

What I find essential is a constant monitor and its integration does not seem easy (I'm still trying to understand what that cable is doing and why a source says to connect it while another source skip the connection). Not sure on how would be possible to connect this device to ESD flooring, all connection schemes shows ESD mats.

[tooki]

You're right, as long as the operator doesn't lift both their feet at the same time and does not seat (in this case a wrist strap is required and I suppose the ESD mat too, the real ones, not the cheap silicon ones as I would like). i think it depends mainly from how an operator feel more comfortable, but I must admit that now I am in doubt. I don't like to stand up and this would require all such expensive stuff which will result in only one (and questionable in terms of percentage) advantage: increased safety.

You shouldn’t be lifting your feet off the ground when sitting, anyway. It’s not ergonomic.

The upshot is this: as long as you remain constantly grounded, whether via a wrist strap or conductive floor or mat, you’re good. (The link above doesn’t want to load right now so I can’t see it, but I’m skeptical of the absolutes (must, required, essential, all, etc.) you throw around so much.)

With ESD flooring I still have doubts about the body skin excluded from the system.

I have no idea what you mean here.

What I find essential is a constant monitor and its integration does not seem easy (I'm still trying to understand what that cable is doing and why a source says to connect it while another source skip the connection). Not sure on how would be possible to connect this device to ESD flooring, all connection schemes shows ESD mats.

Essential? Hardly. That’s the one thing I’ve never seen anywhere yet. They exist so someone must be using them, but I wouldn’t say they’re common, never mind “essential”.

Regardless, you’re overthinking all of this by about a million times.

[Gyro]

Maybe the thread title should be changed as it doesn't match the way it has turned. Constant monitoring of the wrist strap connection is neither cheap nor normal practice in industrial (let alone home) situations. Periodic visual inspection and resistance check with a is generally considered perfectly adequate.

[m k]

Back in the day a good practice was to put crocodile clip away and install banana jacks everywhere.
Then the other end of your wrist wrap is hanging loose.

Around home environment I usually disconnect the wrist side.

[YouCanDoIt]

You're right, as long as the operator doesn't lift both their feet at the same time and does not seat (in this case a wrist strap is required and I suppose the ESD mat too, the real ones, not the cheap silicon ones as I would like). i think it depends mainly from how an operator feel more comfortable, but I must admit that now I am in doubt. I don't like to stand up and this would require all such expensive stuff which will result in only one (and questionable in terms of percentage) advantage: increased safety.

You shouldn’t be lifting your feet off the ground when sitting, anyway. It’s not ergonomic.

Yes, but some people seem to this inadvertently, at least the articles says so (at the time of writing the link is working).

With ESD flooring I still have doubts about the body skin excluded from the system.

I have no idea what you mean here.

I mean to say that the body should be part of the whole circuit, but unlike a wrist strap, there's no direct connection with the skin when using and ESD floor and I'm wondering where does go the electricity accumulated in the body. I'm surely missing something obvious here.

What I find essential is a constant monitor and its integration does not seem easy (I'm still trying to understand what that cable is doing and why a source says to connect it while another source skip the connection). Not sure on how would be possible to connect this device to ESD flooring, all connection schemes shows ESD mats.

Essential? Hardly. That’s the one thing I’ve never seen anywhere yet. They exist so someone must be using them, but I wouldn’t say they’re common, never mind “essential”.

Maybe the thread title should be changed as it doesn't match the way it has turned. Constant monitoring of the wrist strap connection is neither cheap nor normal practice in industrial (let alone home) situations. Periodic visual inspection and resistance check with a is generally considered perfectly adequate.

Perhaps you're right. Companies (and also article published by normal users) tend to use often such words and I should be a bit more suspicious than I normally am. I should have better clarified and say that a constant monitor is essential if someone want to avoid to continuously inspect the equipment. When a wire starts to break and the connection becomes unstable it is not easy to detect through a visual inspection. Same for resistors and in this case a DMM is needed for verification. In addition to that it should be noted that such events can occur at any time, even while working on a system that passed an inspection (I believe "constant monitoring" perfectly describe all of this).
An entry point device is cheap and I think it's worth as long as an user needs to do frequent tasks, otherwise it's a waste of money. I didn't checked what advanced monitoring devices do, but the target of this topic is only a single user, not a factory with plenty of workers.
Gyro, the inclusion of a cheap constant monitoring matches the thread title, but I think you're right, it is now turned into the troubles I'm having with its connection scheme. I'm just posting my findings here because I'm not sure if I should buy a different constant monitor or not. Once I sort this out I will try to not forget to clean up some useless and off topic stuff.

Back in the day a good practice was to put crocodile clip away and install banana jacks everywhere.

This is what I'm doing. Do not be fooled by my posted diagrams showing crocodile clip (to the left side it is shown an adaptor and the crocodile clip is intended to be removed).

[YouCanDoIt]

Ok guys, these are my new findings. I found the same device with another different mark and this one include a more detailed connection scheme:


It has the same hole (although not easily visible here):


Even in this case, there is no connection to this hole. However, step number 6 states that when a mat exceeds 7 meg, the connection should be done like illustrated in fig. 2. I suspect (and I could be perfectly wrong) that this is where the connection to this hole comes into play. I still have to sort out what such "7 meg" means (I can't find anything related on the mat specs).
What this connection does is still unclear, pheraps it connects to an earth point inside the device?