IS requirement

[mpc2123]

Hello all,

This is my first time posting so please bear with me. In a nutshell, is an IS compliant system required if the device (a 24V 4-20mA level transmitter in this case) carries an IS approval? Our client has recently changed the model of level device to one that carries the IS approval. No other level device this client has in their spec has carried the IS rating in the past and my guess is the IS rating was more of a "bell and whistle" that they were unaware of at the time. The manufacturer control dwg shows wired as such (barrier etc.). That said, it is also explosion proof. Is it a violation to install this w/o complying to 504 OR does it simply mean that it is not recognized as being part of an IS system..? Is it a code violation to not install to the control dwg or does it just make it not IS? I'm pretty confused by the situation as I'm sure you can tell. Thanks in advance!

 

[rbalex]

Basically, if you want to use it as part of an Intrinsically Safe (IS) System then it must be installed per the manufacturer's Control Drawing ​[Section 504.10(A)] ; otherwise, it can simply be installed in a manner consistent with Article 501 and Article 504 is irrelevant. In other words, it isn't required to be part of an IS system for simply being identified as IS compatible.

 

[mpc2123]

Basically, if you want to use it as part of an Intrinsically Safe (IS) System then it must be installed per the manufacturer's Control Drawing ​[Section 504.10(A)] ; otherwise, it can simply be installed in a manner consistent with Article 501 and Article 504 is irrelevant. In other words, it isn't required to be part of an IS system for simply being identified as IS compatible.

Thanks Bob! That's what I was thinking. Sincerely appreciate the assistance.