Welcome back to “A Minute with Miranda.” This week we will be covering how the WS Aware provides continuous monitoring for an operator at an SMT line.
The SCS WS Aware Monitor is a continuous monitor for operators, ESD Worksurfaces and metal tools. It will continuously monitor the path-to-ground integrity and body voltage of two operators. It also monitors the path-to-ground integrity of two metal tools. In addition, it continuously monitors for electromagnetic interference (EMI) on two metal tools, which may cause electrical overstress (EOS) damage. The WS Aware Monitor eliminates the need for periodic testing and record keeping of wrist straps.
Per ESD Handbook ESD TR 20.20 section 188.8.131.52.4 “Typical Test programs recommend that wrist straps that are used daily should be tested daily. However, if the products that are being produced are of such value that knowledge of a continuous, reliable ground is needed, then continuous monitoring should be considered or even required.”
View the full range of SCS WS Aware Monitors here.
Welcome back to “A Minute with Miranda.” This week we will be covering how to test ESD footwear entering an ESD Protected Area (EPA).
Per the ESD Handbook ESD TR20.20, A system test of the footwear in combination with the existing or proposed flooring materials in the plant should be made to ensure that the criteria for the facility are met. When using a footwear checker it is important to make sure the upper and lower resistance limits of the checker match the user’s requirements. When testing the footwear should test within the range of 1 x 106 to 1 x 108 ohms.
Heel, sole and toe grounders should be worn on both feet to ensure effective use. They should be worn by all personnel and visitors within an ESD controlled area. If worn improperly, the heel, sole and toe grounders become ineffective. ESD footwear should be tested daily before use within an ESD Protected Area (EPA).
Welcome back to “A Minute with Miranda.” This week we will be covering how the WS Aware Monitor provides for continuous monitoring of an ESD Workstation setup.
The SCS WS Aware Monitor is a dual workstation continuous monitor for operators, ESD Worksurfaces and metal tools. It will continuously monitor the path-to-ground integrity and body voltage of two operators. It also monitors the path-to-ground integrity for two conductive or dissipative worksurfaces and two metal tools. It also continuously monitors for electromagnetic interference (EMI) on two metal tools which may cause electrical overstress (EOS) damage. The WS Aware Monitor eliminates the need for periodic testing and record keeping of wrist straps.
Per the ESD Handbook ESD TR20.20 section 18.4.2 “Some continuous monitors can monitor worksurface ground connections. A test signal is passed through the worksurface and ground connections. Discontinuity or over limit resistance changes cause the monitor to alarm. Worksurface monitors test the electrical connection between the monitor, the worksurface, and the ground point. However, the monitor will not detect insulative contamination on the worksurface.”
View the full range of SCS WS Aware Monitors here.
Welcome back to “A Minute with Miranda.” This week we will be covering why you need to use ESD footwear within your ESD Protected Area (EPA).
Per the ESD Handbook ESD TR20.20, Personnel may also be grounded through the use of ESD footwear with an ESD Flooring system. This method is useful for situations where personnel are mobile or standing in areas where a wrist strap is not feasible and ESDS items must be handled or transported. ESD protective footwear is designed to reduce body charge levels by providing a conductive path from the body to the ESD flooring material.
Heel, sole and toe grounders should be worn on both feet to ensure effective use. They should be worn by all personnel and visitors within an ESD controlled area. If worn improperly, the heel, sole and toe grounders become ineffective. ESD footwear should be tested daily before use within an ESD Protected Area.
Welcome back to “A Minute with Miranda.” This week we will be covering how to properly clean an ESD Worksurface Mat.
For optimum electrical performance, the ESD worksurface mat surface should be cleaned regularly using a recommended ESD mat cleaner. Per the ESD Handbook ESD TR20.20, “Ensure that cleaners that are used do not leave an electrically insulative residue common with some household cleaners.” We recommend using Reztore ESD Surface and Mat Cleaner. Reztore is alcohol free and does not contain silicone or other substances that will leave an insulative residue or inhibit the performance of the ESD worksurface mats.
After cleaning the ESD worksurface mat with Reztore it is recommended to test the surface to ensure that all insulative contaminates such as dirt and grime have been removed from the mat. SCS worksurface mats meet the ANSI/ESD STM4.1 and ANSI/ESD S20.20 required limit of 1 x 106 to less than 1 x 109 ohms for Rtt and Rtg and the recommendations of ANSI/ESD S4.1. View the range of Reztore Alcohol Free products here.
Welcome back to “A Minute with Miranda.” This week we will be discussing how to test the point-to-point resistance (Rtt) and the resistance-to-ground (Rtg) of a Conductive ESD Floor.
ANSI/ESD S20.20 requires initial and periodic verification of an ESD Flooring System. ANSI/ESD STM7.1 outlines the test methods applicable for the Conductive flooring material. For the Point-to-Point resistance (Rtt) test the flooring will be tested with a resistance measurement meter and 2 x 5lbs cylindrical electrodes positioned 36” apart. The value for the test should be less than or equal to 1 x 106 ohms.
The Resistance Point-to-Ground (Rtg) test should be conducted with a resistance measurement meter and 1 x 5lbs cylindrical electrode. One lead from the meter should be connected to the ground point and the other lead will be connected to the electrode. The test value should be less than or equal to 1 x 106 ohms.
View the full range of SCS Surface Resistance Testers here.
Welcome back to “A Minute with Miranda.” This week we will be discussing how to test the point-to-point resistance (or Rpp) of an ESD Smock.
ANSI/ESD S20.20 requires initial and periodic verification of ESD Control items – this includes ESD Smocks. ANSI/ESD STM2.1 outlines the test method applicable for ESD Smocks: the ESD Smock is to be placed on an insulative surface and 2 x 5lbs cylindrical electrodes are to be positioned on each cuff before taking the measurement. The Resistance Point-to-Point Rpp of the groundable smock needs to be less than 1 x 109 ohms.
Welcome back to “A Minute with Miranda.” This week we will be covering how to properly wear a wrist strap.
ANSI/ESD S20.20 requires seated personnel to be
connected to the grounding / equipotential bonding system via a wrist strap.
The total resistance of the Wrist Strap System needs to be less than 3.5 x 10^7 ohms. The key to a wrist strap is
the intimate contact of the band to the skin and that the coil cord is
connected to ground. Wrist straps need to be tested at least daily before
handling any ESD sensitive devices.
Operators can choose between elastic and metal wristbands. Elastic wristbands are comfortable to wear and easy to adjust. Metal wristbands generally last longer and are easier to clean. View the full range of SCS Wrist Straps here.
In today’s connected world, we are surrounded by home monitoring networks, fitness trackers and other smart systems. They all use an IoT platform to keep us up to-date with the current temperature in our house or the number of steps we have taken in a day. There are many different applications of IoT: Consumer, Commercial, Industrial, and Infrastructure, but is there a way to use this incredibly smart technology to improve ESD Control? Let’s take a look!
What Is The Internet of Things (IoT)?
The Internet of Things (IoT) is used everywhere today – from medical devices, to vehicles, to homes and more! Simply put, IoT:
Connects “things” in the physical world to the internet using sensors.
Collects data for these “things” via sensors.
Analyses the collected data and provides a deeper insight into the “things”.
Another broad definition provided for IoT is:
“The Internet of Things (IoT) is the network of physical devices, vehicles, home appliances, and other items embedded with electronics, software, sensors, actuators, and connectivity which enables these things to connect and exchange data, creating opportunities for more direct integration of the physical world into computer-based systems, resulting in efficiency improvements, economic benefits, and reduced human exertions.” [Source]
As mentioned previously, there are many different applications for IoT, but The Industrial Internet of Things (IIoT) applies specifically to manufacturing and industrial processes.
It has slightly different requirements compared to consumer IoT products but the principle is the same: smart machines (incorporating various sensors) accurately and consistently capture and analyze real-time data allowing companies to pick-up problems as soon as (or even before) they appear.
Internet of Things (IoT) and Industry 4.0
IoT helped push the 3rd industrial revolution (machine automation) one step further. “Cyber Physical Systems (CPS) dominate the manufacturing floor, linking real objects with information processing, and virtual objects via the internet. The goal is to converge Operational Technology (OT) and Information Technology (IT).” [Source]
The 4th industrial revolution is also referred to as “Industry 4.0”. “At the very core Industry 4.0 includes the (partial) transfer of autonomy and autonomous decisions to cyber-physical systems and machines, leveraging information systems”. [Source]
Industry 4.0 as fourth industrial revolution [Source]
So, how can companies use the power of IoT and create accessible, real-time feedback on the status of their ESD Control Protected Area (EPA) and ESD control items?
Industry 4.0 IoT Platforms in ESD Control
ESD damages can be extremely costly – especially when it comes to latent defects that are not detected until the damaged component is installed in a customer’s system. Conventional ESD control programs incorporate periodic verification checks of ESD control products to detect any issues that could result in ESD events and ESD damage. The problem is that ESD control products (and the EPA as a whole) are not constantly monitored.
Take an ionizer for example: if a company uses ionization to handle process-essential insulators, the ionizers need to be fully reliable at all times. If an ionizer passes one check but is found to be out of balance at the next, the company faces a huge problem: nobody knows WHEN exactly the ionizer failed or if contributed to a charged insulator potentially causing ESD damage.
The Industry 4.0 IoT platform will be a game changer when it comes to creating a reliable and dependable ESD control program. Sensors collecting vital ESD information like field voltage, Electromagnetic Interference (EMI), temperature, humidity etc. in an EPA will help detect potential threats in real-time allowing supervisors to act even before an ESD threat occurs.
Advantages of Internet of Things (IoT) in ESD Control
Here is a (by no means exhaustive) list of advantages, IoT can bring to ESD Control:
The day in an EPA can be busy. Taking the time to capture and record measurements of ionizers, wrist straps, work surfaces, automated processes etc. can be disruptive and is prone to errors. IoT allows data to be collected automatically without any input from users. This helps to increase the accuracy of data and allows operators and supervisors more time focusing on their actual jobs.
Supervisors have all the essential data in one place right in front of them and can make informed decisions; they can provide feedback and give suggestions in case of an ESD emergency. IoT allows to pinpoint areas of concern and prevent ESD events.
IoT continuously monitors processes and provides a real-time picture of them – no manual checks required. If a potential threat is detected, warnings will show-up immediately. There is no need to worry about potentially damaging sensitive devices because the next scheduled check of ionizers, wrist straps etc. has not been completed yet.
The number one reason for adapting an ESD control program is to reduce costs by:
Enhancing quality and productivity,
Improving customer satisfaction,
Lowering repair, rework and field service costs and
Reducing material, labor and overhead costs.
Reduced Workload and Increased Productivity
IoT pushes all the above even further with the additional benefits of:
Reduced workload for operators: Data is collected remotely without any input from users. Operators are not disrupted in their day-to-day activities.
Reduced workload for supervisors: Supervisors don’t have to collect and analyze data from personnel testers, field meters, monitors etc. The system does it for them and will highlight any issues.
Further increases in productivity and cost reductions: An ESD program can be managed better and with fewer resources.
Static Management Program (SMP): the next generation of ESD Process Control – more information
IoT will no doubt change ESD control and the way EPAs are monitored. Quantifiable data allows companies to see trends, become more proactive and improve the efficiency of their ESD process control system. IoT will support organizations’ efforts to make more dependable products, improve yields, increase automation and provide a measurable return on investment. Not only will this benefit users and supervisors, but the company as a whole.
SCS Static Management Program (SMP) is the only smart ESD system on the market that continuously monitors your entire ESD process control system throughout all stages of manufacturing. SMP captures data from SCS workstation, equipment and ESD event continuous monitors and provides a real-time picture of critical manufacturing processes.
For more information on how to continuously monitor your ESD control program and/or improve an existing program, request a free ESD/EOS Assessment or SMP demo at your facility by one of our knowledgeable local representatives to evaluate your ESD program and answer any ESD questions!
Have you ever walked across a car park on a bright cold winter’s day only to get zapped by your car’s door handle? It’s commonly known that these ‘zaps’ are much more common in cold dry weather. It begs the question: if there are less ‘zap, will using air humidifiers in a manufacturing environment prevent ESD damage of sensitive components? Let’s find out!
Humidity describes the amount of water vapor in the air. There are 3 main measurements of humidity with the most common one being the relative humidity (RH). It is expressed in percent and describes “how much humidity there is in the air, compared to how much there could be. Meteorologists often use the relative humidity as a measurement to describe the weather at various places.” [Source]
At 0% the air is completely dry; at 100% it is so moist that mist or dew can form. The optimum relative humidity level is somewhere between 40% and 60%:
A lower relative humidity increases charge generation as the environment is drier.
If the humidity level is too high, condensation can form on surfaces.
Charge Generation and ElectroStatic Discharge (ESD)
The simple separation of two surfaces generates an ElectroStatic charge. Examples:
Unwinding a roll of tape
Gas or liquid moving through a hose or pipe
A person walking across a floor with heels and soles contacting and separating from the floor
The amount of static electricity generated varies and is affected by materials, friction, area of contact and the relative humidity of the environment. A higher charge is generated at low humidity or in a dry environment.
Once an item has generated a charge, it will want to come into balance. If it is in close enough proximity to a second item, there can be a rapid, spontaneous transfer of electrostatic charge. This is called discharge or ElectroStatic Discharge (ESD).
Going back to our earlier example of getting a zap from your car’s door handle:
Charge generation: you walk across the car park with your soles contacting and separating from the floor. A charge is built-up on you.
ElectroStatic Discharge (ESD): you touch the door handle. Charges move from your body to your car until both are balanced out.
Impact of relative humidity on ESD
Many people will notice a difference in the ability to generate static electricity when the air gets dryer (relative humidity decreases). Relative humidity (RH) directly affects the ability of a surface to store an electrostatic charge. “With a humidity level of 40% RH, surface resistance is lowered on floors, carpets, table mats and other areas. …the moisture in the air forms a thin protective “film” on surfaces that serves as a natural conductor to dissipate electric charges. When humidity drops below 40% RH, this protection disappears, and normal employee activities lead to objects being charged with static electricity.” [Source]
In an electronics manufacturing environment lower humidity may result in lower output from production due to an increase in ESD events during manufacturing processes.
Air Humidification and ESD
Air humidifiers are used to add moisture to the air and are commonly used in drier environments to keep humidity at a constant (optimum) level. Given that a lower humidity level increases the risk of ESD events, the obvious questions are:
Can air humidifiers replace normal ESD Control measures?
Are air humidifiers required for complete ESD protection?
Let’s address both questions:
Let’s be very clear about one thing here: air humidifiers cannot replace ESD Control measures.
As explained further above, ESD is caused by two items that are at a different electrostatic equipotential and want to equalize their charges. Adding moisture to the air using humidifiers will not stop this discharge from happening. The only thing you may achieve is a reduction in the number of ESD events. BUT: they will still happen; just walking across a carpet will generate a charge on an operator. If they then touch an ESD sensitive component, discharge will still occur and may damage the component. No humidifier will prevent this.
The only way to control electrostatic charges on a person or object is through ESD grounding – this will ensure any charges generated dissipate to earth:
For more information on how to create a ESD workstation and how to correctly ground all elements, have a look at this post.
Low air humidity can increase the number of ESD events so it may make sense to keep a factory at a higher humidity level. However, there are many other factors that come into play when choosing the ‘right’ humidity for a manufacturing environment. The recommended humidity range is usually determined by the specifications of the devices and components being assembled. Increasing the humidity in an electronics manufacturing facility can help to reduce ESD events but increased humidity can lead to other unwanted quality issues in an electronics manufacturing environment such as corrosion, soldering defects and the popcorn effect on moisture sensitive devices.
A normal range for humidity in electronics manufacturing is between 30% RH and 70% RH. Some facilities try to maintain a constant moderate RH (~50%), whereas other environments may want lower % RH due to corrosion susceptibility to humidity sensitive parts.
And remember: you will not eliminate ESD by using humidifiers and keeping humidity levels at a higher level. You need an ESD Control Program in place to avoid ESD and associated damages.
Air humidification can help reduce the number of ESD events in an electronics manufacturing environment but at the same time there are other factors (e.g. moisture sensitivity of components) that need to be considered.
A lower relative humidity level increases charge generation as the environment is drier. This will result in more ESD events which can potentially damage sensitive components. The only way to protect sensitive components from ESD damage is by having proper ESD control measures in place and connecting operators, objects and surfaces to ground. This will ensure each element is kept at the same electrical potential and any electrostatic discharge is being removed to ground.
For more information on how to get your ESD control program off the ground or improve an existing program, request a free ESD/EOS Assessment at your facility by one of our knowledgeable local representatives to evaluate your ESD program and answer any ESD questions!