Why is it important to perform an electrostatic discharge before you do the assembling of a computer?

HeadlinesImportant SectorsManufacturing Equipment & Consumables

By Potshangbam July

The increasing demand for electronic devices is fuelling the growth of ESD control products in the market. Tech advancements in the electronics industry, such as the miniaturisation of PCBs and components, have increased the damage caused by electrostatic discharge, as well as the costs. This discharge is very minimal but it’s the heat released that causes the most damage to the devices. This heat can cripple or cause the electronic devices and components to malfunction at any stage—during device manufacture, handling, assembly, testing, field operation, the shipping process, etc. ESD can occur without users feeling any sense of shock and happens while working on the inside of the devices, while handling a cord or other hardware. Therefore, static control becomes very important during electronics manufacturing, which is when ESD products come into the picture.

The importance of ESD products
Any electronic device or component is prone to deterioration because of exposure to ESD, which is the sudden flow of electricity between two electrically charged objects. This occurs when differently charged objects rub against each other, often releasing a visible spark. Even simple movement on a workbench is enough to generate ESD that can damage a device’s delicate electronic components. It can also affect the functionality and quality of electronic products and their components. Therefore, ESD protection products are of great importance to prevent the build-up of static charge in electronic items. Their main function is to reduce the risk of damage to ESD sensitive devices. These protection products are very effective in reducing device failure, and enhance the reliability and life span of delicate electronic items.

To begin with, it is important to create an anti-static EPA (ESD protected area) for the protection of manufacturing areas or workstations. The EPA can be improved by equipping it with ESD-resistant products, such as workbenches, industrial furniture, trolleys, storage bins, etc. There are other items like wristbands, conductive straps, etc, that personnel working in the area can wear to dissipate the ESD safely. All these products are connected to the ground, where the static electricity gets released through earthing points and cables. This helps to dissipate ESD in a much safer way.

The impact of ESD
It is a known fact that ESD is an invisible destructive force that disrupts the normal functioning of electronic devices. It reduces the reliability and life of systems. ESD causes electronic shocks that are harmless and not noticeable to humans. However, they have the potential to destroy electronic devices or parts immediately or over time. Basically, there are two types of ESD damage or defects. In the case of catastrophic damage, the device or component fails immediately and the damage is permanent. The second kind of damage is latent defect, in which case the electronic device continues to function after an ESD related incident, but the damage is a delayed process and the components’ efficiency deteriorates over time. In such cases, it’s not easy to detect the damaged areas as the parts continue to perform for a certain period of time. But, ultimately, the operating life is cut short.

Tips to control and prevent ESD
Listed below are some precautionary measures to help reduce the damage caused by ESD as much as possible while manufacturing, assembling and repairing electronic devices.

• Wearing a grounded wrist strap is highly recommended to reduce the risk of creating an ESD incident. It should be worn correctly, with proper contact with the skin to bring down contact resistance. Since it is connected to the ground, the wrist strap will quickly shield any charge the body generates. To a large extent, it protects sensitive components from ESD damage.
• Repairing of components or the manufacture of PCBs should be done in an ESD-safe and cleanroom environment.
• Using ESD-safe mats on tables or workbenches ensures that static electricity gets dispersed. These mats are designed with electrically conductive carbon fibres. As a result, the ESD is not very active on the surface of the mat, which in turn neutralises it.
• For very sensitive EPAs you may require employees to wear anti-static clothing to prevent ESD shock and shield sensitive components. Such clothing includes T-shirts, sweatshirts, conductive shoes, sole grounders, high visibility jackets, etc.
• Jewellery and other static producing accessories are best not used in the area. This precaution will help to reduce ESD accumulation.
• Use of anti-static tools and equipment avoids the conduction of electrical charge.
  Avoid working on the electronic devices during an electrical storm, as it can increase ESD risks.
• Anti-static bags are efficient in storing the equipment in a safe environment. These bags are also used for packaging PCBs when they are being transported.
• ESD air ionisers remove static charge and particulate matter from the air, which cannot be grounded from the workstation.

ESD safety
Paying extra attention to ESD safety is extremely important for the industries that deal with sensitive electronic equipment. Creating an ESD control programme is the ideal measure to prevent it and address all the relevant problems. Such a programme helps to set up ESD protected areas (EPAs) by identifying items that are vulnerable, including workbenches, tools and equipment, people, objects, etc. This process includes reviewing the workspace environment, and ensuring year-round adequate maintenance and protection. Besides, the ESD control programme should focus on ESD training, grounding, personnel safety equipment, compliance verifications, packaging systems and how to convert or neutralise insulators with ionisers.

All the standards and procedures of the ESD control process should be adhered to and implemented in the right way to create EPAs. Only then can the ESD control mechanisms ensure good results.

Anti-static mat Features: The Hakko 499 anti-static mat is used on floors and tables. It has the appropriate hardness to prevent depressions. The product is phthalic acid-free, and is resistant to wear and tear as well as low levels of dust. Contact: www.hakko.com

Heel grounders Features: Heel grounders are ideal for personnel grounding protection in EPAs. These cup- style grounders are effective in providing a continuous path-to-ground between individuals and ESD-protected flooring. Their white insulated interior prevents carbon marking on shoes, and the plastic parts comprise an anti-static nylon material. Contact: www.aclstaticide.com

ESD anti-static wrist strap Features: This strap from Vastar protects electronic parts from static charges, and is flexible enough to fit any wrist perfectly. It comes with a grounding wire, which ensures safety. It also has an extra-long coiled cord that is adjustable for a wide range of movements. Contact: www.vastar-tech.com

Anti-static finger stall Features: The Hakko 566 anti-static finger stall has no silicone properties. It is chlorine-free, sulphur-free and powder-free. Contact: www.hakko.com

Benchtop air ioniser Features: This ioniser comes with the auto-balance feature that provides fast discharge with low airflow for greater operator comfort. It has electrostatically shielded emitter points and eliminates field-induced charging. Additionally, it is equipped with a two-speed fan. The ionisation performance of this product is consistent at all speeds and allows for use with sensitive applications, such as calibration, test or repair procedures. It requires grounding wires, and is quick and easy to install. Contact: www.staticcontrol.descoindustries.com