We're doing an instrumentation and motor power installation in a Class I, Division 1 space and utilized MC-HL cable because of the customers requirements for limited conduit runs in their production space. We sealed the MC-HL per 501.15(D)(1) using Crouse-Hinds Terminator TMCX connectors at the motors and sensors but did not seal the cables at the boundary between the classified space and the electrical closet where the cables terminated. This was based on our interpretation that the connector was doing "double duty" as I've seen some mention in similar topics to this one, but I can't find in the code book any reference to just needing this one seal and removing the requirement for the boundary seal. Can someone help me out here in finding something I can show the inspector to justify our installation or have we interpreted it incorrectly?
Class I,Division 1 MC-HL Sealing Requirements
- Thread starter LubzinNJ
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- Mission Viejo, CA
- Occupation
- Professional Electrical Engineer
Section 501.15(D) Cable Seals, Class I, Division 1 doesn't mention boundary seals for cables unless they are installed in conduit. If the cable has a gas/vaportight continuous sheath it doesn't need a boundary seal even in conduit although the conduit must still have one. [Section 501.15 (D)(2) + its Exception] Basically, a boundary seal for such a cables serve no purpose since the cable, if sealed per 501.15(D)(1), provides no path for fuels to migrate.
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- Location
- Mission Viejo, CA
- Occupation
- Professional Electrical Engineer
Section 501.15(A) applies only to conduits - the title says so.
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