Class II, Div 1 Requirement for equipment

[Illinois]

A portable unit that we manufacture contains an electric motor (explosion proof Class I C&D, Class II F&G), about 24? of liquidtight conduit and a motor starter which is enclosed in a single gang box. Our customer adds a cord and plugs it into their power source which should be protected with a breaker.

We use only explosion proof motors rated Class I C&D, Class II F&G). I am trying to determine the requirement for the conduit and the enclosure which contains the motor starting switch.

To comply with Class II, Div1, although 502.10 (A) (2) leads me to believe Liquidtite conduit and fittings (Arlington in this case) are acceptable; however, 502.10 (A) (3) leads me to believe that I need both an explosion proof box and fitting for Class II, Div 1. I'm not sure which fittings we have to use, as the two seem to contradict each other. Any guidance?

For the enclosure/box, it seems pretty clear. I suppose we have to go with a box that is rated for Class 2 to be compliant for Class 2, Div 1. I take this to mean we have to use an explosion proof box. Do you agree, or would a Dust Tight box meet the Class 2, Div 1 requirement?

Any help is appreciated. If nothing else, perhaps you can point me in the right direction.

 

[Smart $]

This help?

502.5 Explosionproof Equipment. Explosionproof equipment
and wiring shall not be required and shall not be
acceptable in Class II locations unless also identified for
such locations.

 

[Illinois]

This help?

Thanks for your help. I have to admit I am a little confused in reading that section. "Shall not be required AND shall not be acceptable" seems to contradict itself. Do you think they are saying that it shall not be required by the operating company? In other words, it is not OK for the operating company to insist employees use something that isn't identified for the location? If that is the case, then I read this as saying that the enclosure we use for Class II, Div 1, must be rated as such or in other words, for Class II, Div 1, we'll need to use explosion proof enclosures for the motor starter and for Class II, Div 2, we'll need to use a Dust Tight enclosure.

Thanks again. Any further comments are really appreciated.

 

[petersonra]

What it means is this.

XP is not required, and that just because it is XP does not mean it is acceptable.

It has to be specifically identified (I love that word) as being suitable for a CIID1 area.

It is quite possible for XP stuff to also be identified as suitable for CIID1 areas, but it is not necessarily so.

 

[Illinois]

Thanks Bob. I agree, "identified" could mean a few things. I think we will offer a Class II, Div 1 rated enclosure if someone wants to pay for it. They will then receive a unit that has both a motor AND an enclosure rated and identified on the nameplate for Class II, Div 1. Otherwise, I think we'll just include our dust tight enclosure as our standard along with our standard explosion proof motor. It will be very difficult and expensive to get our entire unit classified as Class II, Div 1 I'm sure. It is sometimes very difficult to know if you are doing the right thing. Thanks again.

 

[Smart $]

Thanks Bob. I agree, "identified" could mean a few things. I think we will offer a Class II, Div 1 rated enclosure if someone wants to pay for it. They will then receive a unit that has both a motor AND an enclosure rated and identified on the nameplate for Class II, Div 1. Otherwise, I think we'll just include our dust tight enclosure as our standard along with our standard explosion proof motor. It will be very difficult and expensive to get our entire unit classified as Class II, Div 1 I'm sure. It is sometimes very difficult to know if you are doing the right thing. Thanks again.

Keep in mind that XP not required/acceptable also extends to the motor. A motor used in Class II environment must be identified as suitable for a Class II location, whether XP or not.

 

[Illinois]

Agree. We just found that it wasn't that expensive to go with Explosion Proof and those motors brought with them a Class 1 C&D and Class II F&G. This only required us to hold one type in stock and wasn't that expensive. Thanks for all of your help.

Albert

 

[petersonra]

Thanks Bob. I agree, "identified" could mean a few things. I think we will offer a Class II, Div 1 rated enclosure if someone wants to pay for it. They will then receive a unit that has both a motor AND an enclosure rated and identified on the nameplate for Class II, Div 1. Otherwise, I think we'll just include our dust tight enclosure as our standard along with our standard explosion proof motor. It will be very difficult and expensive to get our entire unit classified as Class II, Div 1 I'm sure. It is sometimes very difficult to know if you are doing the right thing. Thanks again.

Identified (as applied to equipment). Recognizable as
suitable for the specific purpose, function, use, environment,
application, and so forth, where described in a particular
Code requirement.

That is what "identified" means.

I don't see how you can offer your "standard" dust tight enclosure and claim it is suitable for use in a CIID1 area.

You previously stated the motor is already rated for CIID1 areas so it should not be an issue.

 

[Illinois]

Sorry for the confusion. With the standard enclosure, we're not stating that it is compliant. We simply state today that our equipment contains a motor that is Class I C&D and Class II F&G rated. Since our enclosure isn't identified or rated for such, the best our equipment could be approved for is Class II, Div 2 (since the enclosure and conduit are dust tight).

Funny, your point is actually what started this mess. Once I researched the topic, I believed we need to offer an enclosure that is rated Class II, Div 1 rated and labeled as an option/upgrade for anyone that wants to use our equipment in a Class II, Div 1 environment. Even then, they may struggle as the entire piece of equipment isn't rated, only the electrical components (meaning the enclosure and the motor). Does that make sense?

 

[petersonra]

I think you are playing with fire here. Literally.

If there is an issue, a jury is not going to care much about your parsing of words, only that you sold someone a piece of equipment they reasonably believed was suitable for something that it was not.

Your best bet is to be fully upfront and make it clear the assembly as a whole is only suitable for CIID2.

it does not appear to me that it would be all that hard to change the box out. Maybe some seals and the assembly is OK.

http://www.hoffmanonline.com/produc...at_2=2455&cat_3=81833&catID=81833&itemID=3757

 

[Illinois]

Thanks Bob. I think we're on the same page. Let me know if you agree. I want to clearly list the current model as only being Class II, Div 2 compliant and create a separate option that is Class II, Div 1 compliant. The enclosure I'd like to use for the Class II, Div 1 option is: http://www.emersonindustrial.com/en-us/documentcenter/EGSElectricalGroup/products_documents/controls/haz_loc_controls/haz_loc_ms/eds_fs_manual_ms_contactors/EDS_Series_Factory_Sealed_Manual_11.12.pdf which is an Appleton Motor starter and enclosure (part # EFD175-3MS) that is Class II, Div 1 compliant. By using that, the only other variables are the fittings and the conduit.

Are you for hire to consult? I hate to use your expertise for free as I'm clearly doing now.

Thanks, Albert

 

[petersonra]

Thanks Bob. I think we're on the same page. Let me know if you agree. I want to clearly list the current model as only being Class II, Div 2 compliant and create a separate option that is Class II, Div 1 compliant. The enclosure I'd like to use for the Class II, Div 1 option is: http://www.emersonindustrial.com/en...rs/EDS_Series_Factory_Sealed_Manual_11.12.pdf which is an Appleton Motor starter and enclosure (part # EFD175-3MS) that is Class II, Div 1 compliant. By using that, the only other variables are the fittings and the conduit.

Are you for hire to consult? I hate to use your expertise for free as I'm clearly doing now.

Thanks, Albert

The company I work for no longer does stuff for classified areas.

 

[Illinois]

Too bad. Do you agree with the direction regarding the Div 1 Appleton box as an acceptable option? Assuming we use appropriate conduit and fittings between the Appleton box and the Div 1 rated motor, we should have a Div 1 compliant system. It would be best to have a certified authority review it though.

 

[petersonra]

Too bad. Do you agree with the direction regarding the Div 1 Appleton box as an acceptable option? Assuming we use appropriate conduit and fittings between the Appleton box and the Div 1 rated motor, we should have a Div 1 compliant system. It would be best to have a certified authority review it though.

It would likely be a good idea to have someone who is familiar with CIID1 requirements to take a look. Sometimes there are non-obvious things that may need to be done.

 

[Illinois]

Thanks for all of your help. I agree. Until we can line that up, we're only communicating that we can be Class II, Div 2.

 

[rbalex]

This is an example why, "This Code is not intended as a design specification or an instruction manual for untrained persons." [Section 90.1(A) -2014 NEC] This is especially true for manufacturers/fabricators.

One of our colleagues, a NEMA Field Representative, mentions NEMA will be making coordinated Public Information proposals to eliminate NEMA Type 9 (dust-ignitionproof) in the 2017 NEC. I suspect the reason is that it has finally dawned on enough people that a dusttight system is adequate for Class II - even Division 1 in most cases. The "real" Class II problem is an enclosure's ­external temperatures. [See Section 500.8(B)(1) - parse it carefully]

Properly installed dusttight enclosures can effectively exclude Class II hazardous material from the internal components; Explosionproof enclosures can't exclude Class I materials. I'd been pushing recognizing this since the early 90's. I finally gave up in the late 90's since I was still able to design (and defend) safe, cost effective Class II, Division 1 systems.

 

[Illinois]

Robert Alexander, would you be available for a quick discussion by any chance? I understand what you are saying and believe it. I am looking for some expertise help on the matter and would be happy to pay for it. I agree tbat in reality, a properly designed dust tight enclosure with the correct mounting and conduit will not actually be a hazard even in a class 2, div 1. With that said, I'm quite sure we can't market it that way. I am trying to identify the steps to be able to safely and openly offer a system for use in a class 2, did 1 environment. Any help is appreciated. Thanks