Simple earthing clamps for single- and two-core cables

Simple earthing clamps for single- and two-core cables
Donat Czapski

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Ground clamps with extremely hard and sharp tungsten carbide teeth – one of the hardest conducting materials on earth – guarantee a very secure grip to the object to be grounded, even if it is covered with a layer of paint, laminate, resin, dirt or rust.

Intended use

  • grounding of drums, iBCs, containers
  • grounding of road and rail tankers (cooperation with ground control system)
  • grounding of type C BIG-BAGs

Certifications and compliance

Certifications EX ATEX
FM Global
Certifications IECEx
Certifications PN-EN-13463

Sample applications

Destructive tests

What happens, if we hit the needle-sharp tooth of the ground clamp with all our might with a hammer?

Ground clamp

Very robust, ground clamp with high tooth force which you can easily squeeze with one hand at the same time.

Clamp materialStainless steel 304
Clamp teeth materialTungsten carbide (one of the most durable conductive materials)
Fitting clamp teethIn stainless steel block for maximum stability
Material of spring teethStainless steel 302
Interchangeable teethYes (this extends the life of the clamp to up to several years)
Working temperatureOd -40 do +60°C
Dimensions:Large clamp (VESX90): 240 mm x 105 mm x 33 mm; jaw opening: 40mm
Small clamp (VESX45): 120 mm x 65mm x 25 mm; jaw opening: 15mm
ATEX certificateEx II 1 GD T6 (zgodnie z EN 13463-1 : 2009)
FM Global certificationCertificate of conformity number: 3046346
IECEx certificationIECEx Ex h IIC T6 Ga
Ex h IIIC T85°C Da
Ta = -40°C to +60°C
IECEx EXV 20.0033

Teeth made of the hardest material on earth

Tungsten carbide is one of the hardest conducting materials on earth. It is used, among other things, in anti-tank missiles due to its amazing properties. History tells us that the German military only started using it after it was discovered that it was being used by… Poles. But this is not the topic for today. It is from tungsten carbide that the teeth of our clamps are made. Why? Because tungsten carbide guarantees long-lasting clamp operation and the highest level of safety – the teeth, which remain sharp for a very long time, pierce through paint coating, laminate, dirt or rust with ease. And only then are we able to guarantee a secure and permanent grounding.

Tested durability

The durability of the tungsten carbide teeth has been proven by our test (see video) – it turned out that even a very hard blow with a hammer on a sharpened tooth did not leave any marks on it. For comparison, we performed a second test using a tooth made of steel – we found that the same impact completely destroyed it. The initially sharp tooth of steel has turned into a completely flat bar. The tip of the tooth formed a flat surface approximately 3 mm in diameter.

And what if the teeth become blunt

The teeth in our clamps are incredibly hard. But let’s make it clear, nothing lasts forever. Even tungsten carbide will wear out at some point. What should we do then? Do you have to replace the entire clamp? Absolutely not. Forcing you to do so would not be fair. That is why the teeth in our clamps are interchangeable. Simply unscrew the two screws and replace the teeth with new ones in a matter of minutes. This is a cost-effective and quick solution which means that the bracket can work between a couple and several years.

Example application of ground clamps

Ground clamp with spiral cable

Ground clamp with spiral cable

The simplest solution, which can be connected directly to a cooper or to a ground monitoring system (recommended).

Portable kit with ground test clamp

Portable kit with ground test clamp

The kit, thanks to a controller with an LED integrated with one of the clamps, continuously notifies the operator whether the grounding is effective.

Ground clamp with reel

Ground clamp with reel

The ground cable reel is an ideal alternative to our standard spiral cables.

Grounding control system for tankers

Grounding control system for tankers

Grounding control system for road and rail tankers with a patented three-stage test. Can be coupled to a pump or valve, for example.

Grounding monitoring system with battery power supply

Grounding monitoring system with battery power supply

Grounding control system for drums, iBCs and other tanks and process systems indicating the grounding status via an LED.

Configure your own solution.

How about a welding clamp

Would you trust the clamp if your life depended on it? Welding clamps like the one in the photo taken in one of the factories, or battery clamps do not guarantee reliable grounding. If you have ever charged a battery using them, you will know how insecure is the connection they make – a little movement of the clamp caused it to be lost. In industry, this can cause an explosion or fire.

Key drawbacks of welding and battery clamps:

  1. mostly flat or round surfaces instead of sharp teeth
  2. made of the cheapest materials, including ordinary steel (rusting)
  3. too little jaw pressure

Should I use grounding

The need for electrostatic grounding is primarily imposed by the ATEX directive. It is binding for industrial plants and warehouses, where explosive atmospheres occur to eliminate, among other things, this ignition source. However, let’s forget about the legal requirements for a moment. The need for grounding e.g. tanks, vessels, systems and, in extreme cases, people, is a direct result of practice. Why? Because electrostatic discharge is one of the most common causes of fires and explosions in industry. How is that possible? Let’s take a look at the data below. It turns out that a discharge from even an object as small as a bucket is capable of igniting all the gases and vapours of flammable liquids and even some of the dust.


Energia wyładowania elektrostatycznego: 9 mJ ➡️ jest w stanie zapalić wszystkie pary cieczy palnych, gazy oraz część pyłów.


Energia wyładowania elektrostatycznego: 90 mJ ➡️ jest w stanie zapalić wszystkie pary cieczy palnych, gazy oraz sporą część pyłów.

Tank truck

Energia wyładowania elektrostatycznego: 2250 mJ ➡️ jest w stanie zapalić wszystkie pary cieczy palnych, gazy oraz wszystkie pyły wybuchowe.

Minimum ignition energy of vapours and gases

Explosive atmosphere Minimum ignition energy [mJ]
Propanol 0,65
Ethyl acetate 0,46
Methane 0,28
Hexane 0,24
Methaneol 0,14
Carbon disulphide 0,01

Minimum ignition energy of dust

Dust cloud Minimum ignition energy [mJ]
Wheat flour 50
Sugar 30
Aluminium 10
Epoxy Resin 9
Zircon 5
Certain pharmaceutical intermediates 1

Magnetic clamp

There are situations where it is not possible to connect a conventional ground clamp because the object to be grounded does not have a projecting component. In such cases, a magnetic clamp will work great.

Magnetic clamp ma jeszcze kilka zalet w stosunku do typowych zacisków:

  1. easier operation requiring no effort
  2. the clamp teeth are cushioned, so they wear more slowly
  3. quick connection and disconnection

Electrostatic Earthing – the offer

Earthing control systems

Earth control systems
with process lock (tanks, big bags)

You can use them in the field of earthing monitoring of e.g. road tankers, railways, big-bags, as well as components of process plants. Earth-Rite systems verify easily and safely that the stored loads are properly discharged to the ground through a monitoring unit with a signal lightning diode. If the earthing is not performed properly, the controllers block the process.

Multiple elements earthing control system

Multiple elements
earthing control system

The MULTIPOINT II system is a device designed to control the earthing of up to 8 self-acting or interconnected system components at the same time. According to the guidelines of international standards for the control of unwanted static discharges, the correctness of earthing will only be confirmed by the system if the resistance of the earthing node on each channel is less than 10 Ω.

Clamps with earthing control

Clamps with earthing control
(IBC tanks, drums, big-bags)

We can offer you clamps with monitoring the state of earthing of barrels, tanks, etc. These solutions, in addition to earthing the equipment operating in production rooms, by means of a monitoring unit with a signalling diode, easily and safely verify that the charges accumulated on the equipment are properly discharged to earth.

Simple earthing clamps for single- and two-core cables

wires, spools

Earthing clamps can be used in two configurations – as a set of two simple clamps connected with each other by a spiral cable, or as a connection of the clamp to a earthed container and a ring clamp, which is located at the end of the cable, to a earthing strip.

Shoe inspection stations Ex ATEX

Shoe inspection
stations Ex ATEX

The electrified human body is one of the most serious sources that pose a fire or explosion hazard in industrial conditions. An example of a solution that checks footwear for its ability to dissipate electrostatic charges before an employee enters an area with flammable atmospheres is the Sole-Mate shoe control system.

Secure your industrial plant

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