Tag Archives: anti-static

How do Antistatic Bags Work?

Computer boards and sensitive electronic components need protection from electrostatic discharge, especially at the time of shipping, handling, and assembly. This requirement has led to the development of an entirely new class of antistatic packaging materials. Now, a multi-million dollar packaging industry exists, with major developments in polymers. These are special conductive polyethylene and other laminates covered with very thin metalized films. This packaging industry saves several hundred million dollars each year for the computer and electronic industry, dwarfing almost all other industrial and commercial antistatic abatement enterprises.

To demonstrate the working of an antistatic bag that store and ship assembled boards and electronic components, one needs an apparatus including a tonal electrostatic voltmeter or TESV, several antistatic bags big enough to cover the TESV mounted on a tripod, a plastic tube or rod, and a rubbing cloth. Wool or silk cloth will work well with a Teflon, Nylon, or PVC pipe.

To disallow any movement of the TESV when operating, mount the instrument on a tripod, turn it on, and zero the instrument. Now charge a plastic rod by rubbing it with the cloth, and bring it close to the sensing head of the TESV. The instrument will respond by indicating the presence of electrostatic charge.

Covering the TESV with one of the antistatic bags shows it now registers little or no charge when repeating the experiment. Even with the charged conducting object discharging directly to the bag, the TESV shows little or no charge indication. The only possible explanation is the conductive bag shields the TESV from the electrostatic field.

The bag shields the instrument even though it is not connected to ground. If it were necessary to ground the bag to make it work, the antistatic bag would have been more inconvenient and ineffective than they are now. Grounding is not necessary here as electric charge resides only on the outer surface and does not penetrate inside, or into any void enclosed by the conductive material. The ungrounded bag simply holds the charge harmlessly only on the outside.

This also solves the problem of removing a sensitive component from inside the bag. When a person handles the bag, the contact with the hand grounds the bag and drains the charge from its surface. However, if the person were wearing an insulated glove, the component would draw a strong electric spark when it is withdrawn from the bag, and may be damaged.

Antistatic and static shielding materials are commercially available for every size and shape necessary. Specifications usually refer to MIL standards or the rate of charge dissipation, along with abrasion resistance, thickness, and others. Some advertisers refer to their antistatic bags as Faraday cages, since it does not allow charge to penetrate inside the bag.

Another type of antistatic bag has no metal layer, but is actually a bag made of a conductive polyethylene film. The manufacturer claims the bag can dissipate 5 KV in 2 seconds. Although in practice it is the electric charge that dissipates, the voltage is far easier and more convenient to monitor, and is directly proportional to the charge for a fixed capacitance geometry.

Anti-static electronic component storage bins!

ESD Protection Bins

ESD Protection Bins

Great deal alert! We’re parting with some of our static dissipative stacking bins – taking them out of service in our warehouse. There’s still plenty of life available in these bins so grab them while you can at 60% off the price of new bins.

The bins are perfect for storing all your sensitive electronic components and supplies. Also ideal for a warehouse environment where you need some ESD protection.

Here are the larger size bins: Large Anti-Static Stacking Bin

And here are the medium size bins: Medium Anti-Static Stacking Bin

The price on these bins when new are $26 for the medium size and over $30 for the large size. Both sizes are stackable with an open hopper on the front side for easy access to the contents of the storage bin. Limited availability – only about 200 left.

How Do You Store Your Electronic Components?

Storing and retrieving a large number of electronic components like capacitors, resistors, LEDs, transistors, diodes, ICs etc. can be a daunting task not only because they are tiny but also because extreme temperature and humidity can deteriorate their performance. They also need careful handling as they are fragile and the tips can break easily.

In addition, electronic components need to be protected against static electricity.

To keep static electricity from damaging your sensitive electronic components, we recommend that you use sheets of anti-static foam. These foam sheets are easily cut to size to fit your storage containers.

A sheet of pink anti-static foam

A sheet of pink anti-static foam

There are a variety of container options to store electronic components safely. A range of molded ABS plastic boxes that can be side locked and stacked either vertically or horizontally are available. Each drawer has a number of compartments and can be labeled for easy identification. The various electronic components like resistors, capacitors etc need to be sorted and stored in these compartments in logical fashion. The drawers are easy to slide and can be pulled out / pushed in without much effort.

Ever wonder how the large electronic distributors store and retrieve their components? Automatic storage and retrieval systems make the job of storing and retrieving large numbers of electronic components easy and efficient. A typical construction has a vertical carousel in which a number of cameras are mounted on an endless chain activated by geared motors. The shelves are capable of rotating in either direction in a vertical plane. An electronic keypad facilitates calling the numbered carrier and bin / compartment. The system is equipped to store information about the location of code numbered electronic components in its memory. It can also be linked to a central computer for sharing of information for inventory control purposes. These automatic systems enable fast access of electronic components, instant stock update and save floor space, time, manpower and paper work involved in conventional storage systems.