Class 1 div 1 device in class 2 div 2 area

[james_mcquade]

Hi Everyone,

I have an Application in which the HMI terminal panel is rated class 1, div 2.
My work area is class 2, div 2. I have been looking in the code book to see if
the class 1, div 2 rating would work in the class 2, div 2 area.

I have been told that the most strict code would work for the less strict areas.

Please comment on any code(s) that would help, i'm still wanting to know in the code if this is true for future reference.

Thanks,
James

 

[gadfly56]

Hi Everyone,

I have an Application in which the HMI terminal panel is rated class 1, div 2.
My work area is class 2, div 2. I have been looking in the code book to see if
the class 1, div 2 rating would work in the class 2, div 2 area.

I have been told that the most strict code would work for the less strict areas.

Please comment on any code(s) that would help, i'm still wanting to know in the code if this is true for future reference.

Thanks,
James

Generally speaking, probably not. Class I is for flammable vapors and gases, Class II is combustible or conductive dusts, and Class III is ignitable fibers or flyings. It might seem logical that equipment good for a Class I locations should be good for Class II, but I'd check with the manufacturer to see if it's dual or multiple listed.

 

[weressl]

Hi Everyone,

I have an Application in which the HMI terminal panel is rated class 1, div 2.
My work area is class 2, div 2. I have been looking in the code book to see if
the class 1, div 2 rating would work in the class 2, div 2 area.

I have been told that the most strict code would work for the less strict areas.

Please comment on any code(s) that would help, i'm still wanting to know in the code if this is true for future reference.

Thanks,
James

Classes are signified by Roman numerals and are material dependent, therefore there is no comparative severity exist between them.:
Class I: liguids or gases.
Class II: dusts,
Class III: fibers.

Division is signified by Indian - mistakenly called Arabic - numbers, and signify the likeliness of the ignitable mixture to be present:
Division 1: frequently or normaly present,
Division 2: present only infequently or only due to process equipment failure.

Equipment suitable for more than one Class will be so marked. An equipment marked for Division 1 can always be used in Division 2 WITHIN the same class.

General guideline on your question:


Class II, Division 2 concerns itself with

1. dust exclusion form inside of equipment and some dust-tight equipment can be acceptable to the Code without approval marking fro Class/Division.
2. Hot external surfaces that can be a source of ignition and I doubt your application is such.

Please read the Codebook carefuly and understand the specific requirements for your application.

 

[james_mcquade]

Thanks for the replies,

I should have added in my post that i understand the different class, division classifications.

I will talk to them as suggested. The documentation does not give any other rating other than class 1 div 2.

thanks again,
james

 

[weressl]

I should have added in my post that i understand the different class, division classifications.

Based on your statement in the OP: "I have been told that the most strict code would work for the less strict areas.", I felt that some clarifications were in order.

The documentation does not give any other rating other than class 1 div 2.

You still call it class 1 though......:roll:

 

[gadfly56]

You still call it class 1 though......:roll:

Unless you are going to insist people pronounce it "Class eye", "Class eye eye", and "Class eye eye eye" or some similar convention, this will continue to the heat death of the universe.