Cable Glands Earth Tags Location

[Imumahdi]

Hello Dears,
I have an inquiry regarding a discussion of whether it's acceptable to install earth tags inside the panels. As a non-ex-certified engineer, I don't see any issue of installing them inside in both EX and non-EX enclosures. However, my fellow QA/QC Ex-Certified engineer says it is not acceptable but doesn't mention any reason why it's not acceptable.

Does anyone have an insight regarding this subject?

Would be grateful for any response.

 

[marks1080]

Have you tried asking a certified engineer?

You haven't given enough information for a better response. Depending on where you are you will have different codes to conform to. Also, depending on what these earth tags are and what they're used for will make a difference. If this is related to bonding cable shields to ground than the application will make a difference as well.

 

[waross]

What do mean by "Earth Tags".
I am not familiar with the term.

 

[NickParker]

Earth tags are also called as "Banjo". Earth tags are installed between the Cable gland and equipment to provide an earth bond connection. The reason may be because IP rating of the enclosure may be compromised if you use it inside the enclosures. You need to consult the gland manufacturer to determine whether earth tags can be used inside or outside of enclosure, and specify the type of earth tag being used.

 

[sheimah]

An earth tag is a metallic ring or washer that is installed around a cable gland (where a cable enters an enclosure). Its main purpose is to:
Provide a grounding/earthing connection for the metallic armor or braid of a cable.
Ensure that all exposed conductive parts are at the same potential to prevent shock hazards.
Serve as a path for fault current to flow safely to ground.

IEC 60079-0 Clause 13: Covers the design of Ex enclosures. It requires that any internal parts should not compromise the flameproof integrity.
IEC 60079-14 Clause 10.3.2: Specifies that grounding connections for Ex equipment should be outside the enclosure to avoid creating a potential spark or ignition source inside.

Prevent internal arcing/sparking: If a fault occurs, the arc shouldn't happen inside an Ex enclosure because it can ignite an explosive atmosphere.
Maintain Flameproof Integrity: If you install an earth tag inside the enclosure, you may compromise the IP rating and increase the risk of spark propagation

 

[waross]

Welcome to Eng-Tips, sheimah.