Jun 13, 2022|General
At some point in our lives, we have all experienced the sensation of conducting static electricity. Most people harbor the ability to replicate miniature static by simply walking on a carpet and touching metal afterward.
The scientific term for this power is called electrostatic discharge (ESD), which transfers electrons between two objects.
ESD happens around us daily but often goes unnoticed. Only volt levels greater than 3,500 garnish attention by the human eye, and the damage sustained is about as painful as a small prick on the finger.
As for computers and other devices, ESD is well known as the silent killer. A volt level of 30 is enough to corrupt sensitive data and leave long-sustaining damages.
In the world of technology, understanding ESD, the damages it can cause, and the precautions to take when such a problem arises can go a long way in your business.
Table of Contents
- 1 Electrostatic Charge
- 2 Electrostatic Discharge (ESD)
- 3 How Does ESD Occur?
- 4 How Do You Measure Electrostatic Voltage?
- 5 Types of ESD Damage
- 6 Determining The Cost of ESD Damage
- 7 Electrostatic Discharge Prevention
To understand the potential damage ESD can cause, one must first know how a charge forms in the first place.
All materials can create an electrostatic charge by repeatedly touching and separating from one another, a process known as triboelectric charging. During this exchange, the materials gain or lose their electrons and determine if they are positively or negatively charged.
The amount of electrostatic charge generated depends on a couple of factors, such as the area of contact, the humidity of the surrounding environment, and the speed the two materials separate from one another. The difference in materials also contributes to building up a charge.
Electrostatic Discharge (ESD)
If an electrostatic charge describes the build-up of a charge, then an electrostatic discharge is a spontaneous reaction.
The imbalance of electrical potential between two materials causes the sudden transfer of electricity. When one charged material comes into contact with a dissimilarly charged material, they form an electrostatic field that triggers a spark between the two conductive bodies.
Because ESD is a rapid transfer, it has the potential to generate heat. The greater the charge, the more likely for ESD to leave a burn. There’s minimal damage with human contact, but computers and electronic devices are vulnerable to discharge.
How Does ESD Occur?
There are numerous ways for ESD to occur. The chemistry behind static electricity and the triboelectric effect is the most common way to create a discharge.
Our bodies produce many electrostatic discharges daily. We can build up 500-2500 volt charges a day that barely go unnoticed. At 5000-8000 volts we are able to hear and see any discharges in action.
Synthetic material is known to gather more electrostatic energy, and when placed on or near any electrical equipment, the chances of ESD are high. Electronics near a fan or any device producing fast, non-ionic air movement are prone to ESD.
How Do You Measure Electrostatic Voltage?
The best way to measure electrostatic voltage is by using a voltmeter. This instrument works to gauge the electric current of any particular surface without transferring excessive charge.
With an electrostatic voltmeter, there is a small distance between the tested surface and the probe attached to the device, preventing inaccurate readings as the device won’t interfere with the tested electrical current.
A voltmeter can nullify the electric field between the surface and the device’s probe. This is possible because the voltmeter matches the same voltage levels as the tested surface, and when both are equal, there’s no attempt at altering the charges and allowing the device to give an accurate reading.
Types of ESD Damage
There are three types of ESD events that lead to a damaged device.
Discharge to a Device
This ESD event occurs when a charged conductor discharges to a device. The human body can find ways to accumulate an electrostatic charge and release it through simple contact. For example, picking up your phone after walking across a carpeted floor is enough to set off a discharge of differentiating potential.
Materials with high conductivity, such as metal tools or fixtures, also have the potential to create an electrostatic discharge.
Discharge From a Device
Devices have the potential to collect static charges through handling or separation from packaging materials, machine surfaces, or workbenches. Examples would be devices that move across surfaces or vibrate within a packaged container.
Also known as electrostatic induction, a field-induced discharge is when an electrically charged material is near another object isolated from the ground.
When objects become charged, it also creates an electrostatic field. Items or devices placed within this area can conduct a transfer of charge, and the same reaction can happen when removing those objects from the field.
From these three events, two types of damage can occur.
Catastrophic failures are easy to spot because the damage is visual. Signs of burn marks or oxide failure can insinuate that the device is damaged. The damage is permanent with little chance of recovery.
Latent failure is more about subtle damages. An ESD can happen to the device, but the device continues to run smoothly. Over time, though, the device may show signs of failure without a direct cause.
Determining The Cost of ESD Damage
Being the victim of ESD damage is challenging, especially for a business owner.
Depending on the device, ESD is a costly fix. In the electronics industry, machinery or expensive PBCs that go through ESD damage undergo repairs that cost between 0.5 and 5 billion dollars.
Not only will the costs for repairs and replacements be an issue, but also the level of efficiency in the workplace. If the damaged device acted as an essential component that keeps production going smoothly, then the impact of ESD damages would be grand. Delays would be inevitable until making proper repairs and replacements.
Electrostatic Discharge Prevention
When working with computers or sensitive devices, it is ideal to implement safety measures to prevent ESD damage.
Some of the best practices include working in grounded workstations, wearing ESD-protected shoes and wrist straps, and using packaging materials that don’t generate static charges.
ESD can lurk in the shadows, corrupting your data and damaging your property without you realizing it. It doesn’t take much to cause ESD damage to your device, but the same applies to techniques to keep them safe. It’s always better to implement precautionary measures than to do damage control, and this is especially true when it comes to ESD.