Article 547 help

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nhfire77

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This article does not cover, specifically, concealed control wiring. Just that UF, NMC copper SE.....or other cable suitable for the location.....shall be employed

This is a residential structure per the PE, but article 547 shall apply in most areas. How would you look at Cat6 and fire alarm cable concealed in wall cavity (wood studs) with a solid wood covering?


The PE wont go farther in explanation than --"comply with article 547 and use equipment listed for agricultural or industrial use". AHJ is clueless and will do whatever the PE says, but they have already confirmed copper SE and UF is acceptable.

My thought is if copper SE can be concealed in the wall, so can FPL cable and CAT cable. Not waterproof, but its all copper and water wont be getting into the walls and we are sleeving inside the wall up to 5' to prevent seepage


Regardless-

All cable below 5 feet will be in liquidtite or conduit back to their respective panels in the basement. The cable then transitions to PVC (if the device is not mounted directly to the wall surface) and all devices will be gasketed and comply with Article 503...Class III, Div II specs.

All devices shall be NEMA 4X rated (industrial IMO)
 
What exactly is it you are cabling?

Articles 725, 760 and 800 cover class 2 and 3 circuits, FA systems, and communications cable.

If it's in the wall I would consider that a dry location and most, if not all catx cable is rated for in-wall use. There is a table in chapter 8 that shows the hierarchy of cable types from CMX to CM to CMR to CMP.

If your conduits go underground or outside then they are wet locations by default. You'd probably want direct burial rated cable then; normal comm cable isnt rated for wet locations.

As for hazardous/classified areas, Mr Alexander on this forum is very knowledgeable in those installations and can point you the right way as far as devices, codes, and so on.
 
JFletcher said:
What exactly is it you are cabling?

Articles 725, 760 and 800 cover class 2 and 3 circuits, FA systems, and communications cable.

If it's in the wall I would consider that a dry location and most, if not all catx cable is rated for in-wall use. There is a table in chapter 8 that shows the hierarchy of cable types from CMX to CM to CMR to CMP.

If your conduits go underground or outside then they are wet locations by default. You'd probably want direct burial rated cable then; normal comm cable isnt rated for wet locations.

As for hazardous/classified areas, Mr Alexander on this forum is very knowledgeable in those installations and can point you the right way as far as devices, codes, and so on.
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This isn't a question of what kind of cable for the system, but the location. Its a fire alarm.

The part of this structure is classified as an agricultural building, what I am asking is if in the walls, concealed would FPLP and CMP comply with article 547. The detail about PVC is that its getting protected in the walls upto 5' as a good measure.

The article states wiring methods suitable for the environment. I believe in the wall, above 5' is dry but was looking for opinions and maybe I overlooked something. Again is a residential barn not a commercial operation
 
nhfire77 said:
This article does not cover, specifically, concealed control wiring. Just that UF, NMC copper SE.....or other cable suitable for the location.....shall be employed

This is a residential structure per the PE, but article 547 shall apply in most areas. How would you look at Cat6 and fire alarm cable concealed in wall cavity (wood studs) with a solid wood covering?


The PE wont go farther in explanation than --"comply with article 547 and use equipment listed for agricultural or industrial use". AHJ is clueless and will do whatever the PE says, but they have already confirmed copper SE and UF is acceptable.

My thought is if copper SE can be concealed in the wall, so can FPL cable and CAT cable. Not waterproof, but its all copper and water wont be getting into the walls and we are sleeving inside the wall up to 5' to prevent seepage


Regardless-

All cable below 5 feet will be in liquidtite or conduit back to their respective panels in the basement. The cable then transitions to PVC (if the device is not mounted directly to the wall surface) and all devices will be gasketed and comply with Article 503...Class III, Div II specs.

All devices shall be NEMA 4X rated (industrial IMO)
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I am curious as to how this can be both residential and subject to article 547 given that 547.1 has some pretty stringent conditions that would need to be met to be an article 547 application and no one I know would want to live there if those conditions existed.
 
petersonra said:
I am curious as to how this can be both residential and subject to article 547 given that 547.1 has some pretty stringent conditions that would need to be met to be an article 547 application and no one I know would want to live there if those conditions existed.
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Creative engineering.... They are invoking the International Residential Code (IRC) The PE insists NFPA 150 does not apply. BUT the PE said Art 547 is the correct guidance for this situation in the areas where animals and hay are stored to reduce the risks of dust (of course i think classifying the space as Class III div II would be better, but that's not what they want.)

This is being done because its on a private residential lot BUT there is an apartment on the 2nd floor of the barn, and 547 will not apply withIN the dwelling unit. There will be no commercial ventures, the person living in the barn is only growing food for the residents of the property. No resale.

I feel like within the walls above 5' no dust or water will accumulate. As dust is the issue per the PE not a corrosive environment
 
Dust in these kinds of locations seldom reaches a condition that creates an explosion hazard.

If it did, that wouldn't be all that great for the health of the animals involved either.

If you have a feed mill within the facility where you are grinding hay, corn, etc. you could have a hazardous location in that area.

Moving a few bales around doesn't create anywhere near the dust as running them through a grinder.
 
kwired said:
Dust in these kinds of locations seldom reaches a condition that creates an explosion hazard.

If it did, that wouldn't be all that great for the health of the animals involved either.

If you have a feed mill within the facility where you are grinding hay, corn, etc. you could have a hazardous location in that area.

Moving a few bales around doesn't create anywhere near the dust as running them through a grinder.
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Agreed just looking for opinions on using fplp/cmo cable consealed in the walls in this application
 
nhfire77 said:
Agreed just looking for opinions on using fplp/cmo cable consealed in the walls in this application
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The part of this structure is classified as an agricultural building, what I am asking is if in the walls, concealed would FPLP and CMP comply with article 547.
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I don't see any Code restriction if the cable is suitable for the environment. Would the FA system be addressable?

547 Buildings have a larger rodent problem than other buildings, so adding physical protection to wiring methods is good practice.
 
shortcircuit2 said:
I don't see any Code restriction if the cable is suitable for the environment. Would the FA system be addressable?

547 Buildings have a larger rodent problem than other buildings, so adding physical protection to wiring methods is good practice.
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Agree on both and will add if the cable is inside wood framed wall it is probably not a wet location, framing will not take that moisture very well. If it is wet on one side but not the other then it probably has a moisture resistant covering applied - but inside the wall is dry.

That said cables will leave the wall cavity - if they do enter wet location when they do so then they would still need to be wet location type of cable.
 
kwired said:
Agree on both and will add if the cable is inside wood framed wall it is probably not a wet location, framing will not take that moisture very well. If it is wet on one side but not the other then it probably has a moisture resistant covering applied - but inside the wall is dry.

That said cables will leave the wall cavity - if they do enter wet location when they do so then they would still need to be wet location type of cable.
Click to expand...

Agreed Everything outside the walls will be in pvc and rated NEMA 4X
 
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