ESD Grounding: How ESD Bonding Points Play Their Role

Electrostatic discharge (ESD) grounding is simply the removal or reduction of electrostatic charge between two or more conductive bodies within an electric field, usually with the help of a third body called ESD ground. Sometimes known as ‘grounding plugs’, ESD bonding points play an important role in safeguarding against electrostatic discharge, protecting components or electronic devices during handling or assembly. When you’re creating or maintaining an ESD protected area (EPA), it’s vital to have effective ESD bonding points in places that are accessible.

Article Contents:

• How does ESD protective equipment work?
• What are ESD wrist straps and cords?
• What are ESD footwear and heel straps?
• Why are bonding points needed?
• Finding the right ESD bonding points
• Earth bonding plugs
• Earth bonding brackets
• Benefits of Earth bonding points
• Optimising your EPA
• Customise Earth bonding points with Bondline

How Does ESD Protective Equipment Work?

When working with components which are sensitive to static discharge, such as electrical items i.e. PCBs and ICs, various protective measures should be taken. Typically, this type of work is undertaken in an EPA, where static-minimising and mitigating steps can reduce the risk of static build-up and discharge.

To facilitate this, various protective equipment is used, such as ESD benches with static dissipative properties and ESD flooring or anti-static mats. However, it is ESD wrist straps and cords, along with ESD footwear and heel straps that are most commonly used as protective equipment.

What Are ESD Wrist Straps and Cords?

ESD wrist straps and cords are worn when handling or working with any components which are sensitive to static discharge. These protective devices are worn because the human body can generate static charge, which could then damage sensitive components. By wearing an ESD wrist strap and cord, the operator is ‘grounded’ and the static charge is dissipated to Earth.

Each strap consists of a wrist band with a grounding cord attached to its snap. It is the grounding cord which mitigates the static charge, while the wrist strap ensures the cord remains in place, makes good contact with the skin, and provides additional comfort to the wearer.

What Are ESD Footwear and Heel Straps?

ESD footwear and heel straps work in a similar way to ESD wrist bands and cords; they simply use a different type of product to achieve the same effect. When appropriate flooring is in place, ESD footwear can be used to ground the wearer and prevent static discharge. Similarly, heel straps can be added to an existing pair of shoes to facilitate grounding.

When operators are working in a large EPA or are regularly on their feet, wearing ESD footwear or heel straps can be a more convenient way to safeguard the worker and protect static-sensitive products. However, it is important to ensure appropriate flooring is in place if ESD footwear and heel straps are worn, as an insulated floor will prevent them from providing adequate protection.

Why Are Bonding Points Needed?

Wearing ESD protective equipment, such as a wrist strap, isn’t sufficient to eliminate the risk of static discharge. Instead, the operator needs to ensure that the protective equipment (e.g., the wrist strap) provides a grounding path so that the electrostatic charge can be safely grounded.

An ESD bonding point does just that and makes it easy for operators to ground any electric charges that arise in an ESD protected area. One of the simplest methods to do this is by connecting a bonding point via a grounding socket.

Sometimes referred to as, ‘Earthing a socket’, an Earth bonded plug can be inserted into a regular plug socket. As it only connects to the Earth conductor, it is capable of providing for electrical charges to be grounded.

ESD protective equipment can then be attached to the ESD bonding point, so that any electrical charges travel down the line and are grounded by the Earth conductor. If an operator is wearing an ESD wrist strap, for example, they would attach one end of the grounding cord of the wrist strap to the ESD bonding point, which sits inside a regular plug socket. For best practice, it is recommended that the ground connections use firm fitting connecting devices such as metallic crimps, snaps and banana plugs to connect to designated ground points. If an electrical charge occurs, it will travel down the grounding cord and on to the bonding point, where the Earth conductor will ensure it is grounded.

It is important to note that there should only be one Earth facility connection in your EPA. However, there can be as many Earth bonding points as you require.

Finding the Right ESD Bonding Points

Socket grounding is a common and effective way to protect against static discharge. This can be achieved by inserting an ESD bonding point such as a plug or bracket into a mains Earth. Although a simple method, it is important to select the right bonding point for it to work correctly. Several factors you should consider are:

Type of plug socket connection

You’ll want to ensure that the bonding points you select have European plug sockets if you’re operating within the EU, for example, and a UK plug socket if you’re working within the United Kingdom.

Type of connectors

In addition to this, you’ll need to make sure that the ESD bonding points you choose feature the right connectors for the type of ESD protective equipment you’re using.

A 10mm socket typically features a 10mm stud and 1 meg-ohm resistor as standard, which can be used with most ESD wrist straps, for example. Alternatively, you might need a 4mm banana socket if you’re using ESD protective equipment with this type of connector.

Often, you may require specific connectors or resistance values to match the type of equipment you are using. This can be achieved through customisation. Bondline can provide an array of customisation options for your bonding points, from the size of studs, types of banana sockets, resistance values and posts, to special printing, languages and logos. Typical configurations can include the following below.

Earth Bonding Plugs

Earth bonding plugs offer a simple method of grounding, providing a common ground point using protective Earth in an ESD protected area. They are widely utilised as they can be simply inserted into a mains supply socket anywhere in the EPA. As many operators work at dedicated ESD workbenches, having an Earth bonding plug nearby is always beneficial.

You will find that there are various types of connector points on the front of the bonding plugs. Depending on your requirements, the type of connectors should be chosen according to your needs. If operators routinely work with different types of ESD protective equipment, for example, you might want to choose Earth bonding plugs which feature 10mm studs, M5 posts and banana sockets. Most bonding plugs will have a 1 meg-ohm resistor as standard, although some may have a higher value resistor or no resistor at all. It is important to check what type of connectors and resistance values you need before selecting an Earth bonding plug.

Our range of Earth bonding plugs make it easy to provide a selection of connectors, regardless of how much space you have available. Moreover, they are made to the highest quality and standards as they are manufactured here in the UK.

Types of bonding plugs available from Bondline

• BP (UK, 1 x 10mm stud, no resistor)
• BP3 (UK, 3 x 10mm studs, 1 meg-ohm resistor)
• BP2J (UK, 1 x 10mm stud, 2 x banana sockets, 1 meg-ohm resistor)
• BPR (UK, 1 x 10mm stud, 1 meg-ohm resistor)
• BP210M5 (UK, 2 x 10mm studs, 1 x M5 post, 1 meg-ohm resistor)
• BP2M5 (UK, x 2 M5 posts, 1 meg-ohm resistor)
• BP3S (UK, 1 x 10mm stud, 1 x 7mm stud, 1 x banana socket, 1 meg-ohm resistor)

Each of these bonding plugs are also available in EU plug format with the option to be customised.

Earth Bonding Brackets

As well as using Earth bonding plugs to facilitate grounding, it can be advantageous to have Earth bonding brackets available too. These work in the same way as an Earth bonding plug but can be affixed under a shelf or a workbench for easy access.

Earth bonding brackets work by distinguishing between Earth facility and Earth bonding point. The connection to Earth is made via the supplied 2m standard black wire fitted with a ring terminal. Typically, an Earth bonding bracket will incorporate 1 meg ohm resistors on each individual stud or socket connection.

Again, you can select Earth bonding brackets that feature a range of different connection options to ensure that various types of ESD protective equipment can rely on the bonding point to provide a grounding route.

Our range of Earth bonding brackets come in all sorts of connectors to meet various requirements. They are made to the highest standards as they are manufactured here in the UK. With the option of customisation, there are brackets that suit all.

Types of bonding brackets available from Bondline

• LSBS (3 x 10mm studs, 1 meg-ohm resistor)
• LSBJ (x 3 banana sockets, 1 meg-ohm resistor)
• LSB2J (1 x 10mm stud, 2 x banana sockets, 1 meg-ohm resistor)
• LSB210 (2 x 10mm studs, 1 x banana socket, 1 meg-ohm resistor)
• LSB7 (3 x 7mm studs, 1 meg-ohm resistor)
• LSB7J10 (1 x 7mm stud, 1 x 10mm stud, 1 x banana socket, 1 meg-ohm resistor)
• LSBSB (3 x shrouded safety banana sockets, 1 meg-ohm resistor)
• Earth Facility Bracket (M5 post, no resistor or 10mm stud, no resistor)
• Earthing Point (10mm stud, NO RESISTOR)

Earth Bonding Point Benefits

• Simple and easy method of grounding personnel, ESD work benches, ESD matting and ESD flooring, allowing to be at the same electrical potential.
• Reduction in the static decay rate of workstations.
• Reduction in component damage when handling sensitive electronic devices.
• Luminous yellow with black text for awareness and easy visibility.
• Available as either UK or EU mains connection socket.
• Neutral and mains voltage pins are made from plastic and the Earth pin is metal for guaranteed safety.
• Supports IEC-61340-5-1 and ESD S20.20 ESD Handling standards.

Optimising Your EPA

For companies or organisations that require an EPA, having effective ESD protective equipment is essential. Whether you’re operating with a single ESD workbench, or you have an entire floor as a dedicated EPA, our bonding points and ESD protective equipment enable you to create and maintain a customised workspace that protects employees and keeps components safe from static discharge.

To learn more, explore our range of UK manufactured Earth bonding points now or get in touch with our helpful team at sales@bondline.co.uk.

Customise Earth Bonding Points With Bondline

Our Earth bonding points can be fully customised to match your requirements.

We can provide:

• Specific configurations (i.e. 4mm, 7mm, 10mm stud, 4mm banana sockets, M5 binding post)
• Specific resistance values
• Special printing (i.e. logos, languages)

For specific configurations or special printing of Earth bonding points, please get in touch with us on +44 (0)1793 511000, sales@bondline.co.uk or fill in the form below.