Connectors vs Terminals in Class I, Div 2

[RFUSS]

I am part of a team developing an Ex ec process control instrument for Class I, Division 2 locations and we are at a design crossroads.

I have reached out to some existing customers but I would love to get some feedback from industry professionals with installation experience.

A goal is for the device to not require an enclosure. This limits the wiring methods the are approved under the NEC/CEC. We could connectorize the device with something like a rugged M12 or an M16. This would create a more compact and less expensive device, but we think it would lock end users into a limited number of cable vendors and cable types (These mostly come in ITC/PLTC cable types) and would make certain things like creating serial communication buses or power buses for multiple devices more difficult.

Or we could create a terminal box that attaches to the top of the device with NPT or Metric porting that would allow users to connect armored cable, conduit, or anything else they can terminate to that box. This solution would be bulkier, more expensive and would require some additional electronics design work but it could be more flexible for end users.

How do you feel about connectorized process instruments in hazloc? Would your facility be able to support both ideas? Would you prefer one solution over the other?

 

[petersonra]

I would go with M12

 

[don_resqcapt19]

Are the connectors listed for use in Class I, Division 2 locations as required by 501.114(B)(2)?

Edit: the code reference should have been 501.141....

 

[RFUSS]

Are the connectors listed for use in Class I, Division 2 locations as required by 501.114(B)(2)?

Assuming that the connectors are either listed for Class I, Div 2 or use the NFPA2023 exception related to restricted industrial establishments, warnings, and are just listed for the application.

 

[don_resqcapt19]

Assuming that the connectors are either listed for Class I, Div 2 or use the NFPA2023 exception related to restricted industrial establishments, warnings, and are just listed for the application.

Exception to what section?

 

[RFUSS]

Thank you very much for your time responding to me, Don. I am not an experienced installer and any insight is a giant help.

The exception I was referring to was 501.105(B)(6)(2), based on my attempt to interpolate from the missing 501.114 to 501.105, adjacent to 501.115. I just saw your edit amending the section to 501.141 from 501.114 and now I think we are closer to the same page.

As far as 501.141(B)(2): we would not control the cable connectors, as the device does not come with a cableset, just a receptacle.

I originally envisioned an end user applying 501.10(B)(1) with a PLTC or ITC cable terminated with a listed connector attached to our device's receptacle. but on re-read I see that I interpreted "fitting" as being equivalent to "connector", which it is not.

The combination of 501.141 installation requirements and 501.105(B)(6) requirements suggests that if we use a plug, users will need to use a hazloc rated cordset, be limited to 3 feet of length.

That is not a lot of length! How does anyone do something like an industrial ethernet run in north america if cable lengths are so limited?

 

[don_resqcapt19]

Thank you very much for your time responding to me, Don. I am not an experienced installer and any insight is a giant help.

The exception I was referring to was 501.105(B)(6)(2), based on my attempt to interpolate from the missing 501.114 to 501.105, adjacent to 501.115. I just saw your edit amending the section to 501.141 from 501.114 and now I think we are closer to the same page.

As far as 501.141(B)(2): we would not control the cable connectors, as the device does not come with a cableset, just a receptacle.

I originally envisioned an end user applying 501.10(B)(1) with a PLTC or ITC cable terminated with a listed connector attached to our device's receptacle. but on re-read I see that I interpreted "fitting" as being equivalent to "connector", which it is not.

The combination of 501.141 installation requirements and 501.105(B)(6) requirements suggests that if we use a plug, users will need to use a hazloc rated cordset, be limited to 3 feet of length.

That is not a lot of length! How does anyone do something like an industrial ethernet run in north america if cable lengths are so limited?

While I did a lot of work in classified areas, none of it involved cable wiring methods....all rigid conduit and liquidtight flexible metal conduit. Terminations like you are talking about were in an explosionproof enclosure or a purged and pressurized enclosure.