

Applying Explosion Protection in Automation Technology
Use the WAGO I/O System 750 and 750 XTR to make machines and systems more efficient and safer in atmospheres that are subject to explosion – and do so safely, reliably and economically. The modules within the WAGO I/O System 750 and 750 XTR are designed for use in both non-hazardous and hazardous areas. When used in Zone 2/22 hazardous areas, the I/O System 750 offers safe, easy and economical connection to the sensors/actuators of Zones 0/20 and 1/21. The “blue” Ex i I/O modules were specially developed for this purpose. They form an intrinsically safe segment that can be integrated into a standard fieldbus node, offering all the advantages of state-of-the-art fieldbus technology.
Approved for use in Zone 2/22 hazardous areas for integration of intrinsically safe signals from the field up to Zone 0/20
Comprehensive certification, including ATEX, IECEx, NSI/ISA, INMETRO etc., ensures allows worldwide use
Intrinsically safe inputs with functional safety
Rated up to SIL 3, Cat. 4/PL e PROFIsafe
What does “intrinsically safe” mean?
Explosion Protection in Connection Technology
For safe electrical connection in potentially explosive areas, WAGO offers a broad portfolio of products specifically designed for use in demanding conditions with gas or dust or mining environments. From applications in the control cabinet to device connections and installations with terminal blocks, WAGO products meet all normative approvals and reduce operating costs through maintenance-free and vibration-proof connection technology.
What does “increased safety” mean?
According to the definition in the 60079-7 standard, increased safety is a type of protection applied to electrical equipment or an Ex Component in which additional measures are applied so as to give increased security against the possibility of excessive temperatures and the occurrence of arcs and sparks. In practice, this means that the cross-sections of conductors and insulation distances (creepages and clearances) are increased, and sparking elements (e.g., pluggable connectors) are eliminated. “Increased” represents a “better” electrical design.
Is there anything special I need to pay attention to when using rail-mount terminal blocks in hazardous areas?
First of all, use of Ex e terminal blocks in the equipment requires the manufacturer of the final device to have provided its own assessment. If the terminals are declared Ex components, meaning they have a component certificate with the letter “U” after the certificate number, this means that the manufacturer has assessed the safety aspects of the component (Ex e terminal blocks). None of the familiar certification systems (ATEX, IECEx) requires additional verification of the aspects included in the component certificate.
However, it should be noted that the Ex component cannot be used alone (it is not equipment), and additional factors need to be assessed. One example is junction boxes with rail-mount terminal blocks. Although terminal blocks can be Ex components (marked with Ex e and “U” in the certificate number), the entire equipment and other factors (not assessed in the certificate of the component) must undergo and additional assessment (tests). It should be noted that the heat that arises in such a junction box depends less on the rail-mount terminal blocks used (although they are also important) and more on the number and length of conductors in the box.
What advantages do WAGO rail-mount terminal blocks offer in hazardous areas?
The rail-mount terminal blocks with increased safety (Ex e) WAGO produces are used with success in many explosion-proof devices. These rail-mount terminal blocks, mainly intended for mounting on DIN-rails, are produced in many types for different current ranges. They are subject to certification (third-party assessment) according to the requirements of various certification systems (the conformity assessment per the ATEX Directive, certification per IECEx etc.). Rail-mount terminal blocks are “Ex components” within the meaning of 60079-01 and “components” within the meaning of the ATEX2 Directive.
Are the rail-mount terminal blocks suitable for intrinsically safe circuits?
Rail-mount terminal blocks from WAGO that are marked “Ex e” meet the requirements for intrinsically safe design and can be used in intrinsically safe devices. However, they should be selected on the basis of an analysis (risk assessment) by the manufacturer of the final device.
TOPJOB® S Rail-Mount Terminal Blocks
Maintenance-Free Rail-Mount Terminal Blocks with Ex e I/II Approval
221 Series Compact Splicing Connectors, Ex
221 Series Splicing Connectors for Ex Applications
Signal Conditioners, Relays and Power Supplies with Ex Approval
When space is at a premium, our relay modules and signal conditioners not only meet the requirements of Device Category 3 G/D – they are also just 6 mm wide, making them perfect for overhauling or retrofitting your existing systems. They can be easily configured via DIP switches and provide vibration resistance via Push-in CAGE CLAMP®. WAGO also offers power supplies for use in hazardous areas. Three Eco family models with 24 VDC output voltage and up to 5A output current are suitable for these applications. Thanks to the ATEX and IEC Ex approvals, these power supplies can be used in Zone 2 hazardous areas without difficulty.
Explosion protection is among the legally required safety-relevant tasks for system engineers and planners: Not only is safety of human beings at stake, but uninterrupted production processes and environmental protection are also critical.