Junction box certifcation for internsically safe circuits 2

[murugappan]

Dear al

I have procured EEx certified SS316 JBs with normal color terminal blocks and valid certification is EEXE
Now the 2 or 3 of my circuits are changing to Is
Can I use the same junction box by changing the terminal blocks to Blue, and making extra tag plate to indica IS circuits inside in blue color

Or I need to get it recertified to EExia

Please comment and give the technically best solution

 

[djs]

I don't think that you can mix IS and none IS circuits in the same JB.

 

[murugappan]

I am not mixing the signals

2 or 3 JB will be dedicated for IS circuits only

But y question is only the certification , Is EEx E certified JB cn be accepted for Is circuits

or

Do I need to re certify[highlight #73D216][/highlight] the the JB EExia ib

 

[FreddyNurk]

Its not so much that the signals aren't being mixed, its more that EXia is about limiting the amount of energy on that circuit, thus having non EXia circuits in the same enclosure inside a classified area likely wouldn't be accepted.

Ergo, you're likely to need a separate JB just for the IS circuits only, which in turn renders the original question moot.

 

[murugappan]

Dear Freddy

Your comments well noted. The IS circuits are on a dedicated JB which has only IS circuits

now the next step is whether the JB need to be re certified for EExia ?

or EEXe certified with blue color terminal blocks (eexe ) and blue warning label on the cover will be accepted

 

[ScottyUK]

Technically you don't need a certified junction box at all, so an Ex 'e' box will suffice if you wish to use it, just as a standard junction box would suffice. It would be prudent to identify the fact that it contains I.S. circuits, and the terminals should meet the creepage / clearance requirements of IEC 60079-11 (or your national variant of it).