501.15(E)

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Dale001289

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Scenario: Cable attached to wall mounted LED lighting fixture inunclassified area and terminates in a CGB. It originates fromClass I, Division 2 location inside the building. The Led fixture is not explosionproof and cannot achieve 1500 pascals of pressure…..cable does not have a gas tight continuous sheath. Does the cable termination require a cable seal?
 
The reason I asked what Type cable you were using in my original response is because there is only one Type of cable suitable for Division 2 that doesn't have a gas/vapor tight continuous sheath - an MC type construction using an interlocking metal tape armor.

So, to answer the original question. You don't need a cable seal at the LED luminaire termination; its isn't required to be explosionproof since it's in an unclassified location. [501.15(E)(1)] However, you'll have a helluva problem at the Division 2/unclassified boundary. [501.15(E)(4)]
 
rbalex said:
The reason I asked what Type cable you were using in my original response is because there is only one Type of cable suitable for Division 2 that doesn't have a gas/vapor tight continuous sheath - an MC type construction using an interlocking metal tape armor.

So, to answer the original question. You don't need a cable seal at the LED luminaire termination; its isn't required to be explosionproof since it's in an unclassified location. [501.15(E)(1)] However, you'll have a helluva problem at the Division 2/unclassified boundary. [501.15(E)(4)]
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Bob, the Cable type is TC-ER. The total length is probably less than three feet from the point it leaves the building to connection point at the LED. This means it falls within the boundary of 10 feet therefore per 501.15(E) exception only the termination should be addressed.
Tell me where I'm wrong.
 
The Section 501.15 Exception never applied and I have no idea where your reference to 10 feet comes from.

You described the luminaire as in an unclassified location and origination of the TC-ER cable in a Class I, Division 2 location. Therefor you must have a boundary somewhere.

The luminaire was never required to be explosionproof, so Section 501.15(E)(1) doesn't apply.

The UL White Book states Type TC (Category Code QPOR) is gas/vapor tight. It applies to all forms of Type TC.

This means its sealing requirements are in Section 501.15(E)(3). You may have to go back and parse 501.15(E)(1) carefully, but, unless the cable end in the Division 2 location is attached to process equipment that could exert 1500 Pascals on the cable end, it doesn't have to be sealed. Section 501.15(E)(3) was clearer about this before the 2014 NEC and has been re-clarified in 2017.

In any case, if a seal were required, it would be at the Division 2 termination and not at the boundary or luminaire in the unclassified location.
 
rbalex said:
The Section 501.15 Exception never applied and I have no idea where your reference to 10 feet comes from.

You described the luminaire as in an unclassified location and origination of the TC-ER cable in a Class I, Division 2 location. Therefor you must have a boundary somewhere.

The luminaire was never required to be explosionproof, so Section 501.15(E)(1) doesn't apply.

The UL White Book states Type TC (Category Code QPOR) is gas/vapor tight. It applies to all forms of Type TC.

This means its sealing requirements are in Section 501.15(E)(3). You may have to go back and parse 501.15(E)(1) carefully, but, unless the cable end in the Division 2 location is attached to process equipment that could exert 1500 Pascals on the cable end, it doesn't have to be sealed. Section 501.15(E)(3) was clearer about this before the 2014 NEC and has been re-clarified in 2017.

In any case, if a seal were required, it would be at the Division 2 termination and not at the boundary or luminaire in the unclassified location.
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The Division 2 termination is a simple 'splice' point (Terminal Strip) in a JB within the Building so there's basically zero pascals of pressure and therefore does not need a seal.
My reasoning on the 10 feet (either side of boundary) comes from the section on conduit seals. 501.15(E) section allows TC cable to pass from Division 2 to unclassified without a seal, leaving the only possible sealing requirement at, as you said, the Division 2 termination, not the luminaire.
 
rbalex said:
The reason I asked what Type cable you were using in my original response is because there is only one Type of cable suitable for Division 2 that doesn't have a gas/vapor tight continuous sheath - an MC type construction using an interlocking metal tape armor.

So, to answer the original question. You don't need a cable seal at the LED luminaire termination; its isn't required to be explosionproof since it's in an unclassified location. [501.15(E)(1)] However, you'll have a helluva problem at the Division 2/unclassified boundary. [501.15(E)(4)]
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What about MC-HL cable? Does this also not have a gas/vapor tight continuous sheath?
 
Dale001289 said:
The Division 2 termination is a simple 'splice' point (Terminal Strip) in a JB within the Building so there's basically zero pascals of pressure and therefore does not need a seal.
My reasoning on the 10 feet (either side of boundary) comes from the section on conduit seals. 501.15(E) section allows TC cable to pass from Division 2 to unclassified without a seal, leaving the only possible sealing requirement at, as you said, the Division 2 termination, not the luminaire.
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The JB doesn't meet any of the conditions that requires sealing it per Section 501.15(E)(1) so cable sealing reverts to 501.15(E)(3).

Don't apply conduit rules to cables, unless the cables are actually in conduit. (The rules change a bit). The 10 foot rule was chosen because that is the standard length of a manufactured stick of conduit.

Dale001289 said:
What about MC-HL cable? Does this also not have a gas/vapor tight continuous sheath?
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There are three MC type constructions; see Section 330.116 for their description. MC-HL has a corrugated metallic sheath. Also see Section 501.10(A)(1)(c) for a more specific description.
 
Bob, if TC-ER cables connect to a NEMA 7 enclosure (contains arcing devices) in Class I Division 2 does this cable need to be sealed e.g. C-H TMCX fitting?

Sent from my LG-K330 using Tapatalk
 
Dale001289 said:
Bob, if TC-ER cables connect to a NEMA 7 enclosure (contains arcing devices) in Class I Division 2 does this cable need to be sealed e.g. C-H TMCX fitting?

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Yes. A very rare exception would be when the enclosure as not actually required to be explosionproof.
 
rbalex said:
Yes. A very rare exception would be when the enclosure as not actually required to be explosionproof.
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WE have a device that's described as 'non-incendive' (Open path IR receiver), yet the enclosure is explosion proof, thus I would assume its required to be explosion proof due to internal arcing devices. The general question is, does a non-incendive device preclude cable sealing requirements per 501.15(E)(1)?
 
Dale001289 said:
...The general question is, does a non-incendive device preclude cable sealing requirements per 501.15(E)(1)?
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In general, no. As part of an overall nonincentive wiring system, it might. See Section 501.10(B)(3). But there a lot hoops to jump through. Also refer to ANSI/ISA 12.12.01 for the complete story.
 
rbalex said:
In general, no. As part of an overall nonincentive wiring system, it might. See Section 501.10(B)(3). But there a lot hoops to jump through. Also refer to ANSI/ISA 12.12.01 for the complete story.
Click to expand...


Thanks for all the info.
 
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