Equipotential bonding in potentially explosive areas
Safe together: the EX earthing pipe clamp and the EX equipotential busbar
A risk of explosion lurks here: Companies manufacturing, processing or storing combustible substances, such as the chemical industry or the gas industry, are particularly at risk if there is a lightning strike. With these systems, the requirements for equipotential bonding systems are especially high. According to the VDE directives, all the electrically conductive parts must be connected to the equipotential bonding system. In addition, the arresting paths of the lightning must be created in such a way that neither ignitable sparks nor spray sparks can become the ignition source. Connections of lightning protection systems must also be created in such a way that no ignition sparks are created when the lightning current passes through them. Normally tested connection components in the market can cause dangerous sparks each time lightning current passes through.
Using an Ex equipotential busbar together with an Ex earthing pipe clamp offers extra protection. The OBO portfolio includes both products, providing a safe solution and representing the state of the art.
EX products from OBO – explosion protection from a single source
With EX BES and EX PAS, operators of potentially explosive systems are on the safe side. They are not only tested for high loads in accordance with VDE 0185-561-1 (IEC 62561-1) according to Class H, but have also been tested for Ex areas in accordance with the current test standard CLC/TS 50703-2:2020-12 with different pipe diameters (EX BES), materials and types of connection cables. They can be used in both indoor and outdoor areas. Besides the chemicals and gas industry, they are ideal for use in the pharmaceuticals industry, the food industry, the car industry, in biogas or sewage treatment systems and in the oil industry.
The advantages of EX-tested products from the OBO portfolio at a glance:
- Ignition spark-free lightning protection equipotential bonding
- Suitable for all explosion groups and use in EX zones 1/21 and 2/22
- Independently tested and certified
- Safe electrical contacting
- For equalising temperature-related material expansions
- UV-stabilised and weatherproof
- Suitable for indoor and outdoor applications
- Manufacturer and type designation permanently attached
- Tested according to VDE 0185-561-1 (EN/IEC 62561-1)
- Tested according to CLC/TS 50703-2:2020-12
EX BES earthing pipe clamp
Due to the special requirements for a lack of ignition sparks of connections of lightning protection systems in potentially explosive areas, until now, connections on pipes have been welded or had threaded sleeves. This is not only time-consuming but also expensive. Thanks to the EX BES earthing pipe clamp from OBO, this procedure is no longer necessary.
The EX BAS fulfills the requirement for a lack of ignition sparks and has been tested according to VDE 0185-561-1 (EN/IEC 62561-1) and CLC/TS 50703-2:2020-12 according to the most demanding explosion group, IIC, with a potentially explosive gas mixture.
It can thus be used in all explosion groups for equipotential bonding, even in the explosion groups IIB and IIA. Together with the EX PAS equipotential busbar, it is possible to create lightning potential equipotential bonding free of ignition sparks in potentially explosive areas.
Earthing pipe clamp mounting – simple and uncomplicated
With just one tightening strap, the EX BES offers particularly simple and uncomplicated mounting for all pipes with external diameters from 6 to 500 mm.
The shape of the clip body mechanically prevents the maximum tightening torque from being exceeded and thus offers protection against incorrect clip mounting. The screws are secured against self-loosening and spring washers compensate for temperature-dependent material expansions. This guarantees safe electrical contacting.
The connection can be made using a round conductor made of CU, St/tZn, AL, stainless steel with a diameter of Ø 8/10 mm, fine/multi-wire conductors made of copper with a cross-section of 16 to 35 mm2, with a compression cable lug made of E-Cu (DIN 46235) or a flat conductor made of copper with minimum dimensions 20 x 2.5 mm, with a drill hole of diameter Ø 10.5 mm.
The connection on the other side of the conductor can be created easily with the externally tested EX PAS equipotential busbar using a compression cable lug or the quick-connector, which is free of ignition sparks, for flat conductors.
EX BES - advantages at a glance:
- One clip type for all pipe diameters up to 500 mm
- Fitting made easy: The maximum tightening torque cannot be exceeded thanks to the mechanical locking system
- Two ID fields for labelling
- Clip element insulated from contact element
- Only one tightening strap is required for mounting
EX PAS equipotential busbar
The EX PAS equipotential busbar is used for lightning protection equipotential bonding according to VDE 0185-305-3 (IEC 62305-3) and protective/function equipotential bonding according to DIN VDE 0100 Part 410/540.
The lack of ignition sparks in an explosive atmosphere has been tested according to VDE 0185-561-1 (IEC 62561-1) and CLC/TS 50703-2:2020-12 according to the most demanding explosion group, IIC, with a potentially explosive gas mixture and a lightning current of up to 75 kA.
It can thus be used in all explosion groups, even in the explosion groups IIB and IIA. As the EX PAS equipotential busbar does not possess its own potential source of ignition, it does not come under the European Directive 2014/24/EU.
Thanks to the patented design, the equipotential busbar can be used in a system according to VDE 0165 Part 1 (IEC 60079-14) and VDE 0185-305-3 (IEC 62305-3) in the Ex zones 1/21 and Ex zones 2/22. The patented design of the equipotential busbar comprises UV-stabilised and halogen-free insulation feet. A spring washer to protect the screws acts as protection against loosening.
EX PAS – advantages at a glance
- Patented design
- Made from corrosion-resistant material (stainless steel)
- Suitable for FT, VA, CU and AL material