Surge protection has always been closely linked to lightning protection systems due to the logical link between the management of, and protection against, substantial fault currents. It is pertinent to consider that a structure is usually at greater threat from lightning surge current damage than from the threat of a direct lightning strike.

The previous iteration of lightning protection standard, BS 6651, held information on integrating surge protection devices within an appendix; however BS EN (IEC) 62305 now holds surge protection as a distinct aspect of the standard (part 4), which must be addressed in any structure that claims to be compliant with this standard. BS EN (IEC) 62305-4 recommends a number of methods to protect against transient overvoltages cause by lightning, such as effective earthing and bonding, electromagnetic shielding and line routing, and importantly coordinated surge protection devices; these measures directly impact on the performance of the internal measures of a lightning protection system. The function of the internal lightning protection system is to prevent dangerous sparking between areas of differing electrical potentials, and to prevent the fault currents causing damage in the form of fires, explosions or equipment damage.

A philosophy which underpins the whole of BS EN 62305 is that of lightning protection zones. The concept is that any complex, facility, building or room can be split into zones which have different requirements for lightning protection, and then appropriate protection measures can be broken down into that particular zone. A building may have an external lightning protection system that will stop the building from being damaged, or catching fire. Inside the building there may be equipment such as a computer server within a dedicated room. The server will need further protection to ensure that it is protected from surges, therefore being a lightning protection zone, within a lightning protection zone. It is always worth remembering to attempt to surge protect locally to equipment to ensure that it is managed effectively, and to avoid allowing fault currents inducting downstream of the surge protection device.

Surges can carry through data, power and telephone lines and it is prudent to install surge protection measures on the local power supply to vital equipment, any electronic equipment outside the main structure; particular attention should be given to cables which penetrate the external envelope of the structure. Examples of such items can include CCTV systems, air handling units, power, data and telecom lines, meteorological sensors, aerials, antennas or satellite dish receivers.

Surge performance requirements:

There are three surge protection device classifications: Class I, for protection against direct lightning currents (which is a lightning current arrestor) which activates based upon a 10/350 microsecond current profile. Class II, for protection against indirect lightning effects (which is installed ‘downstream’ from the lightning arrestor) and it is based upon an 8/20 microsecond current profile. Finally there is a Class III surge protection device which is designed for protection against switching overvoltages or localized surges, its performance is based upon a 1.2/50 microsecond and 8/20 microsecond current profile. Some devices can serve as a combined class I and class II device, but it is always important to clarify their performance.

Requirements to install:

As surge protection devices are directly incorporated into electrical circuits it is imperative that they are installed by a trained and competent person. Anyone lacking training and experience in working with electrical circuits should not attempt to install a surge protection device.

Preparation and installation:

Prior to any installation the circuit into which the surge protection device is being installed must be isolated and terminated at the mains. Working in an electrically live area is a potentially lethal hazard and should be avoided. Health and safety measures should be in place to prevent any surge protection device installation works occurring on live circuits. As the installation of a surge protection device is dependent upon the sort of device being installed it is not possible to provide any further information, beyond reasserting the need for all installations to follow the site and task specific installation method statement.

Surge Protection Links

Nature’s unpredictable threat to life

Lightning is an enormously powerful phenomenon which is dramatic to witness but can cause staggering amounts of damage costing hundreds of millions of dollars every year. The effects of lightning can cause damage from its:

• Mechanical effects – the substantial force exerted by the electro-magnetic bolt of energy can cause enormous structural damage; in its search for conductive elements lightning has regularly demonstrated the ability to destroy non-conductive facades, destroy concrete to locate rebar, or even blowing through roof levels. Threats of puncture of metallic roofs through inadequate thickness can be avoided through supplementary measures.
• Thermal effects – lightning can exceed 30000°C, which is staggeringly hot. Whilst it only discharges for a fraction of a second during that time damage can occur, particularly in structures with inadequate lightning protection which can result in lightning causing hot spots which in turn can cause fires. Fires caused by lightning amount to a significant proportion of damage from lightning activity.
• Electro-magnetic effects – lightning can cause an electro-magnetic pulse which can destroy electrical components. Electro-magnetic damage causes millions of dollars in damage costs every year, this is exacerbated by lost data or operational downtime.
• Threats to life – either through the risk of loss of life through fire, or through electrocution resulting from step and touch voltages, people and livestock die every year through lightning. Above all others the threats to life must be the highest priority on any risk assessment.

Whilst one hundred percent protection may not always be possible, through application of lightning protection standards, such as BS EN 62305:2006, can provide effective protection. JMI is frequently sought to undertake various design and technical support services for its clients. Any design will identify the products required to complete the installation. The materials used to create lightning protection systems can be procured from FM Sudafix and this is a further reason that the FM Sudafix Group is often sought for lightning protection projects as it can support the full range of process elements, from inception to completion.

Lightning Protection Links

Rail Products

The FM Sudafix Group has a long association with both light and heavy rail projects. With an original presence through the provision of technical earthing/grounding support and the provision of exothermic welding kits, FM Sudafix have since expanded the rail product range to include rail to rail bonding solutions. These products enable rail contractors to create permanent electrically continuous bonds between the running rails, ensuring that they remain at equal potentials.

Rail projects present unique risk profiles in terms of electrical safety. Be they heavy rail projects or light rail projects, they will inevitably provide the interface between electrical power systems and the public. It is critical that electrical safety systems perform.

Determining the risk profile of a rail project should consider the following issues:

1. Earthing/grounding and bonding: rail systems directly interface with people and for this reason a comprehensive earthing/grounding and bonding system must be in place to protect them.
2. Creating equipotential zones (or zones of equal electrical potential) ensures that electricity does not seek an alternative route of lower resistance; without equipotential zones electricity may find alternative paths to earth, which may be via human beings or conductive elements with which people may come into direct contact.
3. Stray current: if DC electricity is able to leak into the surrounding mass of earth then it will locate conductive elements and discharge through them. In a single instance this is not likely to result in discernable damage, however if the leak is sustained it may very well cause significant damage to conductive underground elements. Stray currents have the potential to migrate significant distances and have been known to cause substantial damage to elements such as reinforcing, steel bridges, underground metallic pipes.
4. Lightning: lightning is an often overlooked threat facing rail projects. As we know, lightning seeks the path of least resistance to enable it to discharge into the strata of the earth. A lightning strike emits a powerful electromagnetic pulse that radiates and has the ability to cause damage. Lightning strikes, both direct and indirect, can result in structural damage, fire, failure/destruction of equipment, and loss of life.
5. Surge: electrical surges have the potential to damage, degrade and destroy electrical elements, and if these are transient overvoltages are not intercepted whole systems can fail. Be they a result of lightning activity or down stream fault current, electrical surges have been known to cause equipment damage, fires and loss of life.

The rail division of the FM Sudafix Group supports numerous rail projects around the globe. Primarily involved in the electrical safety and protective systems on rail projects, FM Sudafix possesses the expertise and renowned service and product portfolio to effectively manage the risk profile of any project. The technical, operations and product departments unite to ensure that the rail projects with which the FM Sudafix Group is involved are protected by the most effective, and installation-practical, electrical safety systems. All aspects relating to electricity on rail projects have to be managed. Any electrical element in a rail system which is not managed has the potential to introduce significant deficiencies, or could manifest into life threatening hazards. A rail project with efficient electrical elements will save money, reduce down time, and most importantly save lives. There is nothing to gain in taking a chance, and everything to gain, from prestige, piece of mind and budget savings, by working with the FM Sudafix Group.

Rail Products Links

Sudaweld Exothermic Welding

Exothermic welding is a process used predominantly to create a permanent connection between two metallic elements that will guarantee conductivity and performance for the lifetime of the earth system. Frequently used by contractors to create reliable bonds to ensure conductivity or to create equipotential zones. The benefit and purpose of equipotential integrated elements is to avoid dangerous sparking between areas of differing electrical potentials. The process results in a weld metal powder superheating and liquefying to release liquid copper on to the conductors requiring connection, which fuses the metals together. The weld metal powders contain a number of sacrificial and contributing ingredients, including copper oxide and aluminium, which facilitate the formation of the exothermic connection. As this process takes only a few moments to complete and does not require any external power source it is ideal for use in remote locations, and project managers with restricted budgets for plant.

Exothermic connections perform more effectively than any mechanical or pressure type surface-to-surface contact connector. Because the connection produced is a molecular bond, an exothermically welded connection will not loosen, independently corrode, or increase in resistance over the lifetime of the installation.

As recommended by IEC and IEEE regulations all earthing system connections should be made by exothermic weld. Connections should include, but not be limited to, all cable to cable splices, all cable to earthing rods, earthing rod splices, cable to steel and cast iron, cable lug terminations, bus bar connections and cable to rail connections.

Advantages of exothermic welding

• Current carrying (fusing) capacity equal to that of the conductor.
• Will not deteriorate with age.
• Permanent molecular bond that cannot loosen or corrode.
• Will withstand repeated faults.
• Low labour costs.
• No special skills required for usage.
• No external power or heat required.
• Can be checked visually for quality.
• Portable and usable even in remote locations.

Exothermic welding is applicable to materials such as

• Copper
• Common steel
• Copper-clad steel
• Bronze
• Wrought iron
• Stainless steel
• Cast iron
• Brass
• Silicon Bronze
• Steel rail
• Columbium
• Commercially pure iron
• Galvanised metals
• Monel
• Niobium

Exothermic Welding Links

EnvirAnode® Cathodic Protection

EnvirAnode® is an environmentally focused cathodic protection system. The EnvirAnode® CPS is first and foremost an effective impressed current cathodic protection solution, familiar, but different: Familiar in that an EnvirAnode® CP system is installed using the same tools and techniques as those used in traditional anode beds, though simpler as the vent pipe and anode centring rings are not required. Different in that an EnvirAnode® CP system is constructed from robust extended life AELAnodes embedded in a conductive impermeable column made from specially formulated Conducrete® backfill material. Installed, this configuration transforms into a molecularly bonded tertiary electronic energy transfer system with a very large active surface area over which the CP energy is effectively dissipated into the soil. This results in the ionic reaction boundary being shifted away from the surface of the anode core to the interface between the column and soil, where the large surface area reduces the circumferential energy density, thereby reducing carbon consumption/depletion by nearly half, and extending the life of the anode bed.

Energy transfer efficiency:

The electronic energy transfer mechanism of the EnvirAnode® gives extremely stable electrical operating behaviour in use, especially when compared to the electrolytic energy transfer utilized in traditional anode beds. The large active, low energy density surface area of the EnvirAnode® column causes minute bubbles of gas to be formed over the entire surface of the column, where it is easily absorbed into the soil before it can collect into concentrated pockets. Thus, by better managing the production and dissipation of out-gassing, vent pipes are not required in EnvirAnode® installations and the overall efficiency of the anode bed is increased. Once the EnvirAnode® column has set up, it provides an impenetrable barrier to the migration of water, eliminating aquifer cross contamination to help maintain the quality of critical water resources. The impermeable characteristic continues even after the carbon has been depleted from the active areas of the column, eliminating expensive abandonment issues and costs. The solid EnvirAnode® column also eliminates the “shelving off” phenomenon inside the bore that degrades the anode bed efficiency and shortens operational lifetimes in traditional coke breeze systems.

EnvirAnode ®performance:

The EnvirAnode® solution offers more reliable and stable electrical performance (and cathodic protective value) over a longer operational lifetime than any other impressed current cathodic protection solutions currently available. The EnvirAnode® is the world’s first molecular bonded tertiary energy transfer technology developed expressly for cathodic protection applications, and is behind its stunning performance as a fully operational, environmentally neutral cathodic protection anode.

If you require further information about this product please refer to our cathodic protection website or the cathodic protection page of this website.

EnvirAnode® Cathodic Protection Links

Defence against fault electrical currents

All construction projects have to address the challenges presented by fault electrical current. A failure to effectively protect against fault current can have disastrous, even fatal consequences. For this reason it is essential that the scale of the potential hazard is established in advance and then specifically addressed through an effective earthing/grounding design and it is for this reason that prudent companies seek JMI to support this provision.

However, an earthing/grounding system design alone will not achieve anything, it is only through the careful application of that design, utilising the products and methods defined in the installation method statements that safety can be achieved, and this system should then be maintained throughout its functional life. These measures are obvious, but so often overlooked or ignored. A design comes from a risk assessment, and the sector recognises the need to follow the measures identified in risk assessments so the design to installation process should be no exception. Focused designers like JMI are able to define the specific products required to complete an installation. Removing ambiguity or need for interpretation ensures that the effective system determined through expert design can be actualised with the exact products. Any departure from those materials identified in the design potentially introduces variables in terms of the performance of a system after it has been installed.

FM Sudafix products, often specified by JMI, are recognised throughout the globe as being of the highest standard. The FM Sudafix portfolio of products has been specified on an array of prestigious construction programmes, including power projects, infrastructure projects, and significant builds. Often sought for rail programmes, the FM Sudafix Group supports a number of light and heavy rail projects either through the provision of technical or design provision or through earthing products, and other associated electrical safety materials.

Earthing Links