EEVblog

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Күн бұрын

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@EEVblog 12 жыл бұрын

Low resistance would upset your circuit placed on it, and potentially be quite dangerous. Static does not have much energy, so easily bleeds away with very high values of resistance.

@chrisrook4193 11 жыл бұрын

Dave, all of you measurements were affected by the ESD mat in this video.

@xtremediy1815 9 жыл бұрын

No they weren't you must be thinking of anti static foam they use for packaging sensitive ic's

@staticanping8277 6 жыл бұрын

@@xtremediy1815Our company have many anti static Ion bar and ionizing air blow in ESD

@Krmpfpks 5 жыл бұрын

5:47 it beeps. So clearly something is being affected!

@vejymonsta3006 5 жыл бұрын

All anti-static gear is within a range of 1M Ohm to 1G Ohm. That is the dissipative range. Values less than 1M are considered conductive and potentially dangerous with grounding errors. This is why all wrist strap assemblies require a 1M Ohm resistor. The upper limit is a bit more complicated, but it primarily has to do with the time it takes to discharge static electricity to ground. It must discharge faster than a human could disconnect from the circuit to ground. 1G Ohm to ground is the standard to prevent human base model ESD events.

@onesleepyshadow 11 жыл бұрын

I had always worried about setting a live board on my mat. Thanks for clearing that up!

@MetalPhreakAU 13 жыл бұрын

Dave, you absolutely must investigate the magnetic effects of pine wood in your next video. NOT using a mat directly on the pine may be causing THEIR measurements to be wrong!

@SnifterRoux 9 ай бұрын

@ 7:22 how did the recipricol of 0.3^(-9) become 3.3GΩ? 50805.3 comes up. Reciprocal of 0.3 x 10^(-9) does however equal 3.3GΩ Perhaps I'm tired and missed something.

@Wishmaster2000 8 жыл бұрын

Thanks for clarifying this myth!

@KeritechElectronics 6 ай бұрын

Did my own test today and my mat went down to hundreds of kΩ on the underside, staying infinite on the upper side. Tested again with my old UT890D+ just to see if it was not a Fluke.

@SigEpBlue 13 жыл бұрын

Super-critical probing. Sounds like a visit to the proctologist. Thanks for going through the extra trouble, Dave.

@chchurchofchrist 11 күн бұрын

1:36 conductive rubber?

@blackstar2008 13 жыл бұрын

@mshine5 Don't forget the thermal noise in the meter and the cosmic backgroung radiation from the big bang and the earths tectonic shift and the virtual particle interference through casimir effect and the nuclear fallout from Japan and the suns solar flares activity of 2012 and the extra-dimension fluctuations from string theory and the quantum particle wave collapse through observation/ measurement. :)

@gamer388 6 жыл бұрын

I've got problems measuring MLCC capacitor value with DMM when the capacitor was direclty on the ESD mat. I've found that when the MLCC capacitor is put on paper it gave me good readings.

@EEVblog 6 жыл бұрын

Then your mat sucks, throw it out.

@gamer388 6 жыл бұрын

Haha it wasn't my personal mat but the one they're using in the lab where I work. They are all black.

@vejymonsta3006 5 жыл бұрын

Paper is dissipative too. Lol

@johnellison3030 3 жыл бұрын

Hello Dave. What brand is the blue mat ?

@joshcook8586 2 жыл бұрын

Oritech

@macnpepperjack 12 жыл бұрын

Can you do a video explaining how these mats work? As a noobie I would think you would want a low resistance mat to discharge the static electricity. Can someone explain?

@goophoba 6 жыл бұрын

From what somebody else just said high voltage low energy static easily dissipates over High Resistance surfaces but honestly I don't get it myself. I'd love for Dave to make a video on this.

@goophoba 6 жыл бұрын

And I'm sure he has I just haven't found it yet.

@ales_xy 5 жыл бұрын

@@goophoba Standard human body model has capacity of 100pF. You can easily discharge such a small capacity through a couple of Gohms. E.g. when charged to 5kV and discharged through 1Gohm, the voltage drops to 200V in cca 320ms. I think the resistance may be even lower for a high voltages, but I don't have any information about that. Also, there isn't just ESD mats, but also wrist bands (not wireless, please :-) ionized air generators, humidifiers, etc. The latter are more expensive and more professional, but the mat + wrist band should be absolute minimum even for hobby users.

@alexandersuvorov2002 5 жыл бұрын

That's just additional ESD protection in addition to wrist band, so there's nothing around you that has any slightest charge. Same as with wrist band mat is just grounded conductor; there's usually a snap in the corner of quality ESD mats that are used to connect mat to the ground and some have two snaps: one for the wrist band wire and second one for the ground wire. This is how I understand it.

@conorstewart2214 5 ай бұрын

DIscharging too quickly can cause problems, especially if it isn't static. If you accidentally touch your power supply positive to the mat then you don't want it shorting to ground through a low resistance. Resistances in the gigaohm range are perfectly fine for dissipating static but you generally do not want a conductive work surface when working with electronics.

@discoHR 8 жыл бұрын

Thanks a lot Dave. I watched this video and took a C64 board, put it on the ESD mat knowing it won't affect anything, powered it on, started measuring the 5V line and almost had a heart attack when the scope displayed 196V! The C64's PSU is isolated but the grounded ESD mat does affect measurements, at least on the scope. Lifted the C64 board to a plastic platform and the problem went away.

@stefanniedzielah1827 7 жыл бұрын

thing is most likely the same would have happend on any other surface. It means you have measured some parasitic voltage.

@CampKohler 13 жыл бұрын

@TheNitramneb That's not his garage. Where have you been? He moved his lab out of the garage to a commercial building months ago. Go back and watch the videos where he first moved in, built his benches, had the King of Australia anoint his toilet, etc.

@limebulls Жыл бұрын

Where can I buy the blue work mat? Can’t find them

@SarahC2 9 жыл бұрын

Dave, I'm looking for a video you did where you show the voltage along a mat that was behaving like a grid of resistors. I thought it was this one, but it's not. Have you any idea of what the link might be? Thanks!

@EEVblog 9 жыл бұрын

Sarah Cartwright Don't recall that. I have my recent one on conductive foam that works like that. And the actual resistor grid video, but recall any others.

@SarahC2 9 жыл бұрын

EEVblog thanks! It must be that one I was thinking of.

@emmetmyers 9 жыл бұрын

Sarah Cartwright I was looking for that same one. There was a vid where a mat was working like a resistor.... maybe i can find it thanks

@staticanping8277 6 жыл бұрын

@@emmetmyers AP&T brand series products include ionizing air blower, ionizing air gun, ion bar, ion nozzle with various specifications are wildly used in semi conduct, encapsulation, opto-electrical, electronics, communication, spray finishing, printing, textile, pharmaceutical equipment, construction material, injection molding industries.

@Infinitesap 3 жыл бұрын

What is the story about the ground wire with 0 ohms or 1M ohms respectfully?

@ekbp3zpe760 3 жыл бұрын

1Mohm is a safety current limiting resistor in the event the user is exposed to 250VAC (or less) by way of the wrist strap in the event of a fault. Note that it doesn't protect you if you are working with voltages larger than 250V as this is the voltage rating of the resistor (250V)

@envisionelec 13 жыл бұрын

You've proved once again that the most outspoken individuals generally have no idea what they're talking about.

@AhmetOmerOzgen 3 жыл бұрын

hello. I need an anti static mat or anythink on my work desk that would discharge me. what is your suggestion? I have my cat on my desk that makes me charged and i am afraid to touch my VA panel (it can kill pixels). what sould get to discharde the ions ?

@qwertyboy1234567899 13 жыл бұрын

Wait, are you sure you had your tongue sticking out at the right angle when you were taking the measurements in the previous video?

@Alex1M6 13 жыл бұрын

Put 40kV across the mat and they soon start conducting (and burning!).

@CampKohler 13 жыл бұрын

@MetalPhreakAU You've got it all wrong. It's not magnetic effects and not pine. What you have to worry about is the static electric charge is built up every time you rub a hard rubber comb with fir.

@CampKohler 13 жыл бұрын

I forgot to bring my earphones to the library, so I couldn't hear the audio. But like the silent movies, the plot came through loud and clear. But there is always the nagging thought that Dave replaced the ESD mat with a sheet of regular plastic of the exact same shade of blue just for this video on the theory you should never give a sucker an even break.

@CampKohler 13 жыл бұрын

@pikuorguk All those old truck tires have to get used somewhere. Grinding them up and making them into mats is a lot cheaper than hauling them off to China... Oh, wait, that's EXACTLY how they got made into mats.

@Tech875O 5 жыл бұрын

So in other words, the ohm resistance is so minuscule that the mat is effectively not even working?

@ales_xy 5 жыл бұрын

ESD mat works. The resistance is miniscule only for regular circuits with regular voltages. Not for static charges, HV circuits or super-sensitive circuits.

@vejymonsta3006 5 жыл бұрын

The mat is doing something. It's just minuscule, because it's incredibly resistive. Like the original response. Standard electronics which are sensitive to static electricity, i.e. integrated circuits, are not going to have the energy to "see" ground through a dissipative material. The effect is negligible, unless you have a super marginal design requirement. Which in that case, you need to bring your product back to design.

@ltkenbo 12 жыл бұрын

No, not in a gigaohm resistance range no way, that would be microamps of current

@mshine5 13 жыл бұрын

Your measurements were completely off. The humidity caused errors because you had the A/C off and were breathing towards the meter as well as touching the mat with your greasy hands. Oh and the lights and camera's electric fields were causing the meter to fluctuate. :)

@MaxKoschuh 9 жыл бұрын

great video. thank you!

@macmcseboy 13 жыл бұрын

Dave, what brand mats do you use, I'm looking to replace the stuff on my benches at work.

@staticanping8277 6 жыл бұрын

AP&T brand series products include ionizing air blower, ionizing air gun, ion bar, ion nozzle with various specifications are wildly used in semi conduct, encapsulation, opto-electrical, electronics, communication, spray finishing, printing, textile, pharmaceutical equipment, construction material, injection molding industries. If you have any interesting, please feel free to contact us.(Email:Nicole@sh-anping.com.cn) Thanks.

@circle601 12 жыл бұрын

a faraday cage should work to reduce outside interference

@MoviezDepot 10 жыл бұрын

Is this also safe when using a mat, that your power point(powerbar) is switched off & plug into the outlet. Also that the PSU is switched off and plug into the powerbar. Use a motherboard Standoffs on the psu screw hole & attaching the alligator clip to the standoffs. Is this okay? is the mat grounded? This is a brand new build. What if its not a brand new build, what do u suggest?

@dumle29 10 жыл бұрын

are you talking about assembling a desktop computer? You will be fine doing that on your desk.

@staticanping8277 6 жыл бұрын

@robbiemurdza4115 10 жыл бұрын

what do you mean that it "doesn't do anything" i guess i am a bit confused... what measurements... i just bought a pretty expensive mat for working on computer hardware and now i am skeptical that i just wasted money on something i might not need.

@firestorm517 10 жыл бұрын

The mat doesn't affect any measurement readings. The mat's do what they are supposed to and designed to do.Don't worry.

@robbiemurdza4115 10 жыл бұрын

ah... that makes me feel better... thanks!

@Satchmoeddie1 10 жыл бұрын

I was thinking "horseshit" myself. Unless you are doping microscopic silicon semicons and monitoring the process, that is not going to make any difference. I noticed that with some of the critical power supplies for power plants stock brokerage hoses, etc, were sensitive enough to sway the readings on the meters as I moved about the room. You are affecting the readings with your body far far more than those mats. My antiquated Teague ESI LCR shows a reading way up in the gigohms range with 50 volts externally biased placed across the mat at a distance of 1cm. That is just absurd. That being said, what type of shoes are you wearing, and what color is your underwear? If anything, the mats probably bring some stability to the readings.

@germancarfan 4 жыл бұрын

What is the exact mat you have?

@vejymonsta3006 5 жыл бұрын

Whoa whoa! That mat is not calibrated, Dave! Gotta send that back to the cal lab before you start doing REAL work.

@TheXGamer969 13 жыл бұрын

Great job busting all the BS info out there! You're the EE Mythbuster!

$@frac$

@frac 13 жыл бұрын

But what angle was your tongue at?!

@eried 13 жыл бұрын

maybe the mat affected the measurements

@Alice_Fumo 6 жыл бұрын

I'm not even sure what these mats are supposed to do that would possibly help against ESD. Can anyone explain?

@pikuorguk 13 жыл бұрын

I've got a cheapo rubber mat. It *stinks* of rubber but seems mostly resistant to soldering irons and knives. But my god... it stinks of cheap rubber.

@afivey 13 жыл бұрын

Maybe the blue affected the commenters' brains? Do any of your more expensive multimeter's measure blue?

@DLTX1007 13 жыл бұрын

Been on a roll , lately ?

@sepertude 13 жыл бұрын

Oh Dave.....!!! We could se Fluke 87V vs Gossen Metrawatt Xtra instead of this :)))

@stickboyfpv4742 Ай бұрын

The cheaper one is hamagenous.... Hamagenous mats wont work with esd monitoring😅 like a desco monitor😊 in case annyyyones wonderingg😂

@mrhoogles 3 жыл бұрын

conductive.... rubber?

@envisionelec 13 жыл бұрын

@macmcseboy The most expensive ones you can find. Seriously. ;)

@topbanana188 11 жыл бұрын

* affect

@Sevalecan 5 жыл бұрын

I feel like you were less angry here than you are now....

@ondraster 13 жыл бұрын

It would be bad mat, if it would have some capacitance, wouldn't it?It would charge, you'd put some expensive chip on it and BOOM, it would discharge! ;)

@RandyLott 13 жыл бұрын

You're a married man. It doesn't work if you are. That's what they told me at least ;)

@EEVblog 13 жыл бұрын

@mshine5 Luckily, all cancelled out by the current phase of the moon.

@xKatjaxPurrsx 12 жыл бұрын

eh... i guess a rubber ESD mat wouldn't be very helpful with my GLASS workbench. :P

@staticanping8277 6 жыл бұрын

@thekaiser4333 6 жыл бұрын

EEVblog 0:50 Rubber? Antistatic??!! Pfffffttttfftttffffthahahaaahahaha! Hahahaha! Please tell Robert Jemison Van De Graaff about it!! What is this here? Kangaroo science? People these days.... bloody unbelievable!

@williammarin5639 6 жыл бұрын

bloody unbelievable @the kaiser you thinking that your comment is a contribution, not to mention you have none videos either. Van de Graaff generators use a motorized insulating belt (usually made of rubber)...

@thekaiser4333 6 жыл бұрын

It's a static electricity collection belt made of rubber.

@ales_xy 5 жыл бұрын

@@thekaiser4333 There are many rubber materials and even more additives. In this case of ESD mat, both rubbers - the blue and the black - are nitrile rubber. One is conductive, one is not. Why? Because additives. I have LDPE ziplock bags. Ones are regular white LDPE bags, ones are static dissipative pink coloured LDPE bags. When you take regular bag and rub it on clean hairs, you get sparks crackling. When you do the same with ESD bag, you get nothing. And now the best part. When you swipe the ESD bag with alcohol, seemingly nothing changed. It's still pink LDPE bag. But when you rub it, it generates static charge as regular bag. My theory is, there is some surface treatment or material additive, which can be washed away with organic solvent.