Personal Grounding

Transforming Technologies is proud to announce the addition of the HG1360NM-2 to our line of ESD heel grounders.

Non-marking heel grounders are valuable because they help keep your controlled environment clean. The HG1360NM-2 is constructed from a non-marking and highly dissipative three layer rubber. The reversible 1.5” wide rubber cup, secures both at the back and underneath the heel. Its 7.5” length rubber provides enough cup volume to fit comfortably on those with larger shoe sizes. The 7” stretch hook and loop enclosure ensures a comfort fit. For more information, download HG1360NM-2 Data Sheet.

Features

• High Visibility Blue Color
• Non-Marking Rubber
• Buried resistor

For price and availability on the HG1360NM-2 or for information on any products in Transforming Technologies full line of ESD products, please call 419-841-9552 or email eric@transforming-technologies.com.

ESD Protection in the Field
Static damage is a constant threat anywhere micro-electronic components are used, but these components are at highest risk during servicing. The Transforming Technologies’ FSM2424 Field Service Kit is designed to quickly and reliably remove static charge on the service technician and provide a safe static-free surface to lay parts. The kit includes a 24” x 24” rugged mat with two 8” x 12” pockets for storing tools, an adjustable wrist band, coil cord and 15’ ground cord.
The FSM2424 Field Service Kits eliminates static charge through the principle of grounding. Both the mat and the operator’s wrist band connect to the specialized ground cord which when properly connected to ground, provides a safe path for static charges to drain to ground.

Field Service Procedure
1. Upon arrival at the service call site, unpack the field service kit in a convenient area near the equipment to be serviced.
2. Remove any accessories from the pockets and attach the ground cord to the mat via one of the two snaps found in the corner of the mat.
3. Connect the opposite end of the cord to a reliable ground. Common ground locations are water pipes, unpainted equipment frames, and building frames.
4. Slip on the wrist band and adjust the size to fit comfortably around the wrist but tight enough to make contact with the skin at all times. Snap the coil cord to the wrist band.
5. Insert the banana plug of the coil cord into the jack of the ground cord. This connects the wrist band to the same common ground as the work surface.
6. It is now safe to remove and handle static-sensitive components.

Field Service Care
The FSM2424 Field Service Kits can be cleaned with ESD-safe mat and surface cleaner or with a mild detergent and water as needed. Once clean, allow the material to air dry, removing any excess water/moisture with an absorbent cloth. DO NOT use heat of any kind to dry mat. Though inherently flame resistant, the field service products will burn with enough exposure to open flame or other heat sources of sufficient temperature. DO NOT use a clothes dryer, as the excess heat may cause the PVC material to retain the shape it held in the dryer. Most strong solvents are not recommended. AVOID: Halogens, concentrated Oxidizing Agents, Ethers, ketones, and Low-Molecular Weight Solvents derived from the Ether and ketones fami-lies. They include (but are not limited to) TetraHydroFuran (THF), Methyl Ethyl ketone (MEK), Methyl Isobutyl Ketone (MIBK) and Acetone. These chemicals will mar and/or destroy the sur-face of the PVC product (the Ketones), react with it (Oxidizing Agents), or actually dissolve it (THF and other Ethers). Wrist strap can be hand or machined washed.

For information on resistance monitoring, dual conductor grounding products or any general questions, please contact Transforming Technologies at 419-841-9552 or email at info@transforming-technologies.com.

One Meg Vs Two Meg Heel Grounders

Introduction

Have you ever wondered what it means when a heel grounder described as having a “1 meg resistor”? or a 2 meg resistor?  The size of a current limiting resistor is often included in the description  of personal grounding products, but what does it mean and how concerned should I be with the size of the resistor when I am buying heel grounders?  Today we will answer these questions but first some background:

What is a Resistor?

A common resistor

A resistor is a component of an electrical circuit that resists the flow of electrical current. A resistor has two terminals across which electricity must pass, and is designed to drop the voltage of the current as it flows from one terminal to the next. A resistor is primarily used to create and maintain a known safe current . Most grounding products have a current limiting resistor and it is most commonly one megohm, rated at least 1/4 watt with a working voltage rating of 250 volts. This ensures that the flowing current will be within safe levels.

Heel Grounders and ESD Protection?
Heel grounders discharge static from a person to ground by connecting the person to a grounded walking surface. A heel grounder is made from a conductive material and is worn on each shoe.  A conductive ribbon placed inside the wearer’s shoe or sock makes electrical contact with the skin through perspiration. The ribbon is joined to a resistor which limits current should accidental exposure to electricity that may  occur. The other end of the resistor is joined to a conductive sole. This sole contacts a grounded ESD floor mat or ESD flooring system. Heel grounders should be worn on both feet to maintain ground contact while walking. UL and OSHA recommends a minimum of 1 megohm resistance to ground (RTG) in order to limit current for safety purposes.

Types of Heel Grounders?
Heel Grounders come in a variety of styles:

• Cup Style: Made with two reversible soles for longer life span.
• Foot Grounder: Provides a more complete path-to-ground due to wider contact area and heel-to-toe coverage.
• Disposable: Strip of conductive material is applied to shoe. Economical and perfect for one time use.
• Toe Grounder: Ideal for high heels when standard heel grounders won’t fit properly.

Resistors and Heel Grounders
Heel grounders come with either a 1 megohm or 2 megohm resistor. When one foot is on the ground, a 1 megohm heel grounder gives you an RTG of 1 megohm and a 2 megohm heel grounders results in 2 megohm RTG. But when both feet are on the ground, the sum of the resistors yield a RTG of 1/2 that measurement.
For example:

• When you wear two, 1 megohm heel grounders and have both feet on the floor, your RTG is only 1/2 megohm, NOT 1 megohm!
• If you wear two, 2 megohm heel grounders an have both feet on the ground, your RTG is 1 megohm.
• By wearing two heel grounders with a 2 megohm resistor you are complying with UL and OSHA at all times.

This can be sometimes confusing.  So we made a diagram to illustrate:

Conclusion

Heel grounders are an effective and popular way to ground mobile personnel in ESD areas. Heel grounders use built in resistors to limit any potential current that flows through the device to ensure operator safety.  The size of the resistor that you use depends on the standards of the specific operation,  but by wearing two heel grounders with a 2 megohm resistor you are complying with UL and OSHA at all times.

To learn more about ESD heel grounders and Resistors, visit Transforming Technologies.com