40

There are two types of anti-static bag: static-dissipative (pink, red, or occasionally black) and static-discharge (silver or grey). Static-dissipative bags are designed to remove any static build-up that gradually builds up during shipping by transferring the charge to ground (i.e. what-ever the bag is touching). However, they are not designed to handle ...


27

You (and the some of the other answers) focus too much on the actual value of the resistance to ground; the fact is that the actual value is irrelevant regarding ESD. The ESD charge just needs a path. If that path is high-ohmic (few mega-ohms) it will only take slightly longer for the charge to find its way to ground. But it will still be a fraction of a ...


22

If your plastic pellets are getting charged, you can flood the inside of the silo with ionized air using a commercial generator. These are not uncommon in the plastics industry.


20

The 1meg resistor is needed to safeguard the user from faults from other equipment connected to mains earth. Keep in mind that the wrist strap is a permanent connection to the electric system of the building. If another piece of equipment experiences a fault, there could be a big fault current through the mains earth wiring system. That means that, in ...


16

It makes no difference where you connect the anti-static strap to your body. The reason is that your body is much lower resistance between any two points than the strap is. Also, most of the resistance between any two points on your skin is getting thru the skin at each point. You're just a bag of saltwater (electrically, anyway). The bag has a ...


11

Electrically, it doesn't matter where it makes contact, with contact being the key word! I find however that it doesn't suit my workflow round either wrist or ankle. If worn on my wrist, the trailing wire interferes with stuff on my bench. If worn on my ankle, it's a long way down to attach and detach, and being out of sight, it's easy to be working for a ...


11

Your series resistance of 150 kΩ is very high. That's simply not giving the crystal enough drive, and drops the overall loop gain too low. Try much lower values. Also, check that 33 pF is a valid load cap value. Often these low power "watch" crystals are rated for just 5-10 pF. Basically, read the datasheet of the crystal. None of the above ...


10

Here is an excerpt from chapter 7 of Note: copying images because PDF files are protected and text cannot be copied. BTW: here you will find the entire book freely: OP AMP APPLICATIONS.


10

No, it will be fine. Just take the inner ESD bag fully out of the outer bag before removing the motherboard. The ESD bag ensures that all parts of the motherboard are at the same voltage. Any static charges on the outer bag will be evenly distributed by the inner one.


10

Beware the "audiophile" hi-fi market, there is a lot of very dubious product sold, often at crazy prices, to exploit and generally befuddle the innocent. In this category, we might include items such as: speaker cables that claim to have almost magical properties, including but not limited to, directionality. The function of a speaker cable is to ...


9

There are several considerations for your wrist strap. A) Safety for you B) Safety for your fragile components and kit C) Process, use them correctly D) Grounded? A) Your safety Your wrist strap should include a large amount of current limiting before connecting to a real earth. In practice, this is a 1meg resistor in the strap, and/or where you clip it ...


7

You have two questions which you think are related since they both concern ground connections. However the questions are not related ! Q1) The actual ground connection, where the return current from the supply flows, are the black wires on the ATX power connector. Indeed the chassis is also connected to the motherboard via the screws but this connection is ...


6

You can't easily do what you ask since the problem is charge gets built up on the plastic particles. Since they are all enclosed in one uniform conductor, it won't matter what the voltage of this conductor (the tank wall) is. There will still be charges on the plastic particles relative to the tank wall. Changing the voltage of the tank wall will only ...


6

You are right. If you wear gloves, they should be sufficiently conductive so that their surface does not retain a charge, which gets discharged through you to your connection to ground. The purpose of all ESD precautions is to get everything at the same potential. It doesn't have to be 'ground', but that is the most convenient level to choose. So insulators ...


6

What is special about these screwdrivers that makes them ESD safe compared to other screwdrivers? The data sheet for that T4741SESD screwdriver set explains that: The handles are [...] electrostatically dissipative to DIN EN 61340 5,1 & 5,2 That is the difference. Therefore if you working at an ESD workstation, wearing an earthed wriststrap ...


5

It's part of the degaussing system. "Degaussing" refers to removing any residual permanent magnetic field. This is important because electron beams are deflected by magnetic fields. Residual magnetism in parts of the unit can cause strange abberations and color fringes in the picture. To degauss the unit, a strong AC current that gradually diminishes is ...


5

EOS/ESD prevention Experience The reason for the acceptable range of 1M to 10 M is to current limit static discharge for wrist straps. in addition it reduces current to live voltages. --- added *Although Vac line voltage both IEC/UL acceptable leakage is 500uA for line filters etc, so one could reason that the wrist strap could be reduced to 240k with ...


5

The point about static electricity is that there's usually not that much energy, i.e. charge, building up over a short time. Therefore, a couple kOhms resistance don't make that much difference - your body voltage would break down over that. I'd argue that the fabric ones are better for most usage scenarios: they are simply more comfortable to wear, and ...


5

Ionized air is frequently used for static control in industrial processes. If you simply google for "ionized air static control", you'll find many commercial products.


5

When you say your tools are not ESD safe, do you mean they are all metal? As in all metal tweezers? Or that they have a metal working end but have plastic handles? Like screwdrivers and pliers? I would have no qualms about all metal tools since you are wearing the ESD wrist strap when you are grabbing the tool anyways. Technically, all-metal tools aren't as ...


4

Your anti-static wrist strap should include a built-in resistor in the order of 1MOhm. If the resistor is present, it is safe to connect the wrist wrap to earth. If not it is dangerous, because any voltage present in the equipment you are working with would easily discharge through you and the wrist-wrap.


4

"Touching with bare hands" will MOMENTARILY DISCHARGE your body PRIOR to handling any static-sensitive objects (boards, chips, etc.) Using a wrist-strap will CONTINUOUSLY drain any static charge and keep you safe from zapping anything you touch. If you could do whatever with one hand, then touching the case of the computer accomplishes essentially the ...


4

Bad plan because: no one does it that way because it is not needed you could cause other problems by making extra connections The best way to do this is like in your picture but without connecting anything to the graphics card. Personally I would also not connect anything to the PC case because if you place it on the ESD mat, it is sufficiently grounded ...


4

You first have to understand what is damaged by static discharge. It's a MOS transistors' gate electrode insulation layer. That layer is so thin it breaks through at 5..20V applied to it against source or drain, and the minimal currents of a static discharge are enough to create a conductible path through it. Which, in result, fries the device as soon real ...


4

In addition to the other comments/replies, I'll add that an ESD wristband, by itself, doesn't provide much benefit if your goal is to prevent electrical overstress (EOS) due to electrostatic discharge (ESD). You also require a work surface made of engineered, static-dissipative material that is electrically bonded to the same ground as your ESD wristband. :...


4

A VandeGraaff generator is a mechanical current-pump attached to a small-value capacitor. On a good day, the rubber belt is creating perhaps 10uA: a constant ten microamps. The VDG sphere forms a capacitor, with the Earth as the second plate, and the usual capacitor value is well below 50pF. Very tiny! When we connect our belt-driven constant-current ...


4

If you can discern the static charge, it's too much to be safe for chips. If you're buying chips from a reputable source they're already coming to you in anti-static bags -- just leave them in. Any passive, non-semiconductor component (i.e. caps, coils & resistors) should be fine with a bit of static electricity.


3

According to the standard ESD test arrangement (as in description of IEC 61000-4-2), the arrangement must have a solid aluminum ground plate. The plate must be grounded via TWO 500kOhm resistors (in series) to ground. This limits ESD discharge currents while providing reasonable discharge (RC) time. The "anti-static" mats are safety devices, and whoever ...


3

No. Just be sure that it is properly connected to whatever reference you have around. The table/bench you work on should also be at the same potential, and if possible also use an anti static mat and chair. All those does not need to be grounded, but they do need to be connected to the same potential. If ground is available ground them. You probably do ...


3

That box is conceivably suitable - but much less so than many alternatives. The box is collapsible and not liable to be very strong mechanically. The power supplies are 'not light' and it would require some sort of internal frame to add strength and rigidity Cooling with power supplies is liable to be a significant issue. If both inlet and exhaust airflow ...


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