Marconite – Electrically Conductive Aggregate Material
uploaded by Chris Dodds - Thorne & Derrick Sales & Marketing Manager
Marconite, the low resistant earthing solution, combined with copper earth rods and copper lattice mats has been delivered from stock to provide essential earthing protection to vital S&T infrastructure on the Network Rail infrastructure in the UK.
Marconite, the electrically conductive aggregate material, conducts electricity much in the same way as metals, through the movement of electrons.
Traditional earthing materials, such as Bentonite, conduct electricity through the movement of charged ions. These ions require the presence of an effective electrolyte, such as water and the presence of salts. Unlike Marconite, ionic based systems are subject to drying out and without water they do not conduct electricity.
Bentonite
Marconite does not need water to conduct electricity and so does not suffer any effects from drying out.
Marconite is the world’s premium electrically conductive aggregate material. Used as a backfill to enhance the effects of earth electrodes, such as copper bond earth rods, Marconite enables electrical and civil engineers to achieve permanent, stable and low resistance earthing solutions, even in difficult ground conditions.
Specifically developed for the needs of the earthing industry, for over 40 years Marconite has allowed electrical engineers to tackle the toughest conditions and achieve the satisfactory earthing of installations throughout the world.
Marconite is a synthetic material manufactured specifically for use in earthing applications and, unlike Bentonite, it is not a naturally occurring mineral or ore.
Marconite has distinctive properties result from a unique manufacturing process, utilising specific raw material feedstocks, carefully selected and mixed in tightly controlled ratio’s before undergoing a range manufacturing process and thermal treatments.
The resulting product is a precisely measured, granular material, dark grey in colour, that is virtually dust free and with exceptional electrical properties. This is then packaged in high strength, UV resistant valve topped sacks and palletised.
Marconite is the low resistant building and substation earthing solution for rail projects.
Marconite Conductive Concrete is a registered product of the James Durrans Group and is solely produced by their subsidiary company Carbon International Limited. T&D provide fast delivery and competitive prices for genuine Marconite brand Earthing Products.
Contact T&D for Copper Earthing Tapes – Bare Tape & Covered
To complement Earthing & Lightning Protection products we stock and distribute the most extensive range of copper earthing equipment.
Thorne & Derrick – Stockists & Suppliers of MV HV Joints, Terminations & Connectors
uploaded by Chris Dodds - Thorne & Derrick Sales & Marketing Manager
Thorne & Derrick are a leading distributor of Earthing & Lightning Protection Systems, including Marconite, the world’s premium electrically conductive aggregate material.
Marconite compound is used as a backfill to enhance the earthing effects of copper earthing rods – Marconite enables permanent, stable and low resistance earthing solutions even in difficult ground and soil conditions.
Pictured below T&D off-loading recent Marconite delivery of over 1000no 25kg bags – T&D can provide most competitive prices and delivery schedules for Marconite in the UK.
Thorne & Derrick are distributors of LV-HV Cable Installation, Cable Jointing & Electrical Equipment – we service UK and global businesses involved in cable installations, cable jointing, earthing, substation and electrical construction at LV, 11kV, 33kV and EHV.
T&D service utilities, power, construction, rail, mining, offshore, oil, gas and petrochemical industries. T&D distribute Electrical Safety Equipment protecting workers on underground cables, overhead powerlines, switchgear and substations at LV, MV and HV.
Contact T&D for Copper Earthing Tapes – Bare Tape & Covered
To complement Earthing & Lightning Protection products we stock and distribute the most extensive range of copper earthing equipment.
Marconite
uploaded by Chris Dodds - Thorne & Derrick Sales & Marketing Manager
Marconite is developed and manufactured specifically for use in electrical earthing installations enabling electrical engineers and earthing system designers to achieve permanent, stable and low resistance earthing solutions even in difficult ground or soil conditions – typically used for substation earthing applications.
Adding Bentonite and similar earthing compounds, such as Marconite, in a trench or larger drilled hole around the electrode, typically an earth rod, has the effect of increasing the surface area of the earth conductor, assuming the resistivity of the added material is lower than that of the surrounding soil.
Earthing Compunds
Marconite compound is a precisely measured, granular material, dark grey in colour, that is virtually dust free and with exceptional electrical properties.
| Marconite Earthing Compound Benefits | |
| Low Resistivity | 0.001 ohm.m is extremely low when compared to Bentonite’s 3 ohm.m |
| Versatile | Suitable for most ground conditions and becomes a permanent, solid structure that it is not prone to shrinking, drying out or being washed away |
| Cost Effective | It is a permanent solution; there is no need to remove and replace or ‘maintain’ it with additional water / salts every few years in order to achieve the desired earth values |
| Chemically Inert | Is non-corrosive to steel or copper, does not attack cement structures and has a pH within the neutral range |
| High Strength | Can be used as part of the building structure itself and can achieve strengths higher than Grade 25 concrete |
| Easy To Use | Forms a concrete like material that from first pour, achieves a low resistance earth, no need to wait or return to test |
Marconite is essentially a conductive concrete in which a carbonaceous aggregate replaces the normal aggregate used in the conventional concrete mix – Marconite earthing compound has some similar properties to Bentonite, i.e. causes minimal corrosion with certain metals and has a low resistivity. It was developed as a process which started in 1962 when Marconi engineers sought a material which conducted by movement of electrons rather than ions. It contains a crystalline form of carbon and the overall material has a low sulphur and chloride content.
There is stated to be some corrosion of ferrous metal and copper whilst the Marconite is in slurry form, but it is suggested that a thin protective layer forms. When the concrete has set, corrosion is said to cease. Metal should ideally be painted with bitumen or a bitumastic paint as it enters the Marconite structure to prevent corrosion at this point. Aluminium, tin coated or galvanised steel should not be installed in Marconite.
When Marconite is mixed with concrete, its resistivity can fall to as low as 0.1 Ohm-metre. It will retain its moisture even under quite dry conditions so has been used in the hotter climates as an alternative to Bentonite compound. Its principle application in the UK is at locations where theft or third party interference is likely to be a problem, or to enclose copper electrodes in bore-holes or voids within rock when driven into the ground.
When surrounding an earth rod with Marconite which has been installed in rock, the resistance of the copper earth rod will be reduced as the volume of Marconite used is increased. For example, if a 1 metre earth rod is installed at the centre of a hemisphere of Marconite of radius 1.5m, it would have a resistance of approximately 2,000 Ohm if the surrounding rock is of 2,000 Ohm-metres.
Call T&D for Copper Earthing Tapes | Best Prices | Large Stocks
If the radius of the hemishere is increased to 3 metre and then 5 metre, the resistance would fall to 1,080 Ohm and 650 Ohm respectively. Because of the prohibitive cost of removing such a volume of rock, it makes sense to make use of existing cavities for this purpose, where possible. Also, the void is likely to be part filled with other materials (such as concrete) to reduce the amount of proprietary material required. Marconite is normally considered as having a resistivity of 2 Ohm-metres.
T&D provide fast delivery and competitive prices for genuine Marconite brand earthing compounds.
Marconite – Electrically Conductive Aggregate Material
To complement Earthing & Lightning Protection & Exothermic Welding products we stock and distribute the most extensive range of copper earthing equipment.
uploaded by Chris Dodds - Thorne & Derrick Sales & Marketing Manager
Marconite is the world’s leading premium electrically conductive backfill material which significantly enhances the effects of copper earth electrodes to reduce the resistance of a lightning protection or copper earthing system.
Marconite is a dark grey, granular material that replaces traditional sand and aggregate materials used within concrete mixes – it should be mixed in the ratio of 3 parts of Marconite to 1 part cement by weight with addition of 1 litre of water per 4kg of total mix:
3 x 25 Kg bags of Marconite
1 x 25 Kg bag of Cement
25 litres (25 Kg) of Water
Ground enhancement materials such as Bentonite and Marconite earthing compounds are used to lower the resistance to earth of Earthing & Lightning Protection Systems – simple to install and used as backfill for earth electrodes, including earth rods or earth mats.
When mixed as described above, the Marconite forms a relatively dry material with an ‘as poured’ density of around 1300 Kg / m³ for earthing purposes.
The water content may be adjusted as the application requires, but this will affect the concretes final compressive strength and the drying times accordingly.
Typically Marconite concretes are touch dry within hours but can be several days before being fully cured.
Marconite is chemically inert with very low soluble sulphate content. It can be used with all conventional types of cement, as well as most proprietary resin-based cements, adhesives and gypsum plasters – due to the inert structure Marconite is non-corrosive to steel or copper and with a pH level in the neutral range will not degrade or erode cement structures.
Marconite Conductive Concrete is a registered product of the James Durrans Group and is solely produced by their subsidiary company Carbon International Limited.
Marconite earthing aggregate provides exceptional resistivity with a resistance level of .001 ohm.m – even when mixed with cement the resulting resistance level is only 0.19 ohms.m.
Reducing Earth Electrode Resistance
Marconite is a conductive carbonaceous aggregate which, when mixed with conventional cement, has the effect of increasing the surface area of the earth electrode, thus helping to slightly lower its resistance. These earthing back-fill materials can provide a significant improvement to earthing system performance but also provide several secondary functions: maintain the resistance value at a more constant level throughout the year, to provide protection against 3rd party damage, or to protect the earthing electrode from corrosion.
Marconite is also useful for surrounding electrodes installed in rock.
Where a decision is taken to use FurseCEM, Bentonite, Marconite or any other special back-fill material, the design engineer should ensure that this information is passed to the construction staff – construction methods can be used to limit the amount used and therefore associated cost.
Examples are mixing Bentonite with local clay, reducing the hole diameter drilled (for vertical copper electrodes) and minimising the width and volume of the horizontal trench section into which the earth electrode will be installed.
Contact T&D for Copper Earthing Tapes – Bare Tape & Covered
Marconite – Electrically Conductive Aggregate Material
To complement Earthing & Lightning Protection products we stock and distribute the most extensive range of copper earthing equipment.
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