Ex approvals

If systems are installed in potentially explosive areas, a large number of safety precautions must be taken.

The requirements placed on electrical equipment for use in areas with a danger of gas explosions are described in the IEC/EN 60079 series of standards.

The conformance of COMBICON Ex PCB terminal blocks with the requirements for increased safety is confirmed by EC-type examination certificates and markings for directives and standards.

These documents and installation notes containing important information about the correct use of PCB terminal blocks in areas with increased safety can be found in the Download Center.

General information

For product-specific information, please refer to the installation notes.

• PCB terminal blocks are designed for installation in suitable housing. When used in environments containing potentially explosive gases or dust, this housing must meet the applicable requirements of IEC 60079-0 and IEC 60079-7 or IEC 61241.
  
  The PCB terminal blocks must be installed in a wiring space or housing so that they are secured against rotating or accidental loosening.
  
  
• For information about additional fixings, please refer to the installation notes.
  
  
• When connecting conductors, make sure that the wire insulation extends right up to the clamping point. Following installation of the PCB terminal blocks in a wiring space with increased safety "e" protection type, the air and creepage distances must meet the requirements of IEC 60079-7. These requirements apply in particular to the mixed installation of different components and when using additional accessories.
  
  
• When using cross-sections smaller than the rated cross-section specified in the EC-type examination certificate, the corresponding lower current value must be specified in the EC-type examination certificate for the device.
  
  
• Depending on the type of terminal block, the specified voltage can be increased using pitch spacers. The voltages resulting from the use of one or more spacers can be found in the EC-type examination certificate. We will be happy to confirm which other combinations are supported.

Intrinsic safety "i"

For intrinsic safety "i" protection type according to IEC 60079-11, both PCB terminal blocks with Ex e-approval and standard products can be used. They are simply used as electrical equipment and do not require any particular certification or markings.

Make sure that the air and creepage distances required in connection with intrinsically safe circuits are observed. The connection points of these circuits must be clearly labeled. If labeling is by means of color-coding, the connection points must be light blue.

Labeling

Explosion-protected electrical equipment must be labeled in such a way that the safety-related properties can be implemented correctly.

Note: In accordance with the specifications of the ATEX Directive, components such as PCB terminal blocks are excluded from CE marking.

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