Question article 350 LFMC install 3 phase 480 install

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Kyell

Kyell

Member
Location
Titusville Florida USA
Hello Forum,

I need help finding a reference for LFMC and an install from a disconnect to a transformer.
I have my code book out and I searching my art 350. I am installing LFMC with an internal ground wound up within it. I am using Metal LIQUID tight fittings made for this product, as I have many times before. I want to use grounding bushing at both ends. However I am being ordered to remove both my grounding bushings and my Liquid tight fitting and use only liquid tight pvc fittings because it is outdoors and they do not want to see rust. I am beside myself and I have to address this with a honest good argument on Monday. I have faced this before the cutting corners etc. and it is driving my professionalism nuts.

K
 
tom baker

tom baker

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LFMC is not restricted to dry locations, indeed the title is liquidtight, which would mean outside. Its also approved for direct burial if listed for that. LFNC fittings are required to be listed and are they listed for LFMC? Probably not. If there is a concern with corrosion there are PVC coated fittings and HDG fittings available.
Perhaps someone can post how to get to the UL White Book where the listing information is for the fittings
 
kwired

kwired

Electron manager
Location
NE Nebraska
Kyell said:
Hello Forum,

I need help finding a reference for LFMC and an install from a disconnect to a transformer.
I have my code book out and I searching my art 350. I am installing LFMC with an internal ground wound up within it. I am using Metal LIQUID tight fittings made for this product, as I have many times before. I want to use grounding bushing at both ends. However I am being ordered to remove both my grounding bushings and my Liquid tight fitting and use only liquid tight pvc fittings because it is outdoors and they do not want to see rust. I am beside myself and I have to address this with a honest good argument on Monday. I have faced this before the cutting corners etc. and it is driving my professionalism nuts.

K
Click to expand...
Why are they going to see rust? If anything if you route the flex so there is a "trap" in it it will collect water there and rust the raceway out at that point over time.
 
tom baker

tom baker

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Yes thats an issue with no GB on metallic flex, missed that. Why not use LFNC? I like the T&B black product and nylon connectors. Its pretty tough stuff
 
Kyell

Kyell

Member
Location
Titusville Florida USA
In my eyes it is because of poor planning and design, the transformer and disconnect are located "almost" in the drip edge of the metal building. I did not design it and I STRONGLY objected to it, Then when I requested to install grounding bushings I was asked why do I have to spend the money on that when you have, an equipment ground already.
 
Kyell

Kyell

Member
Location
Titusville Florida USA
sorry about my last post got to "clickly", all they have on site is PVC "carflex" and they will probably want me to use that with PVC fittings
not my design and NOT what I want
 
ActionDave

ActionDave

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Kyell said:
In my eyes it is because of poor planning and design, the transformer and disconnect are located "almost" in the drip edge of the metal building. I did not design it and I STRONGLY objected to it, Then when I requested to install grounding bushings I was asked why do I have to spend the money on that when you have, an equipment ground already.
Click to expand...
It's a good question. Why do you feel the need to install grounding bushings?
 
Kyell

Kyell

Member
Location
Titusville Florida USA
with LFMC I have always installed Grounding bushings to insure completed bond and ground.... I have even requested for new ground rods to be driven since NONE exist and the point this feeds from is more than 200 feet away this OUT building has NO Ground rods either.....I am so tired of fighting to do things right. even when I site code the response is.....there is no inspection on this DOD facility.
 
infinity

infinity

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Unless you have concentric or eccentric KO'S you don't need bonding bushings on LFMC. If they are worried about rust just use LFNC.
 
Kyell

Kyell

Member
Location
Titusville Florida USA
infinity said:
Unless you have concentric or eccentric KO'S you don't need bonding bushings on LFMC. If they are worried about rust just use LFNC.
Click to expand...



Actually I do have concentric KO on the main distribution panel.

I probably will use LFNC if any is in stock ...they do NOT like ordering anything "extra" remember my last post "the response is.....there is no inspection on this DOD facility".
 
don_resqcapt19

don_resqcapt19

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Location
Illinois
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retired electrician
Are there non-metallic fittings that are listed for use with LFMC? Even if there are, I would red tag the installation based on 250.4(A)(2). The LFMC itself needs to be connected to the circuit EGC and if you use non-metallic connectors, there is no way to do that.

In my projects I have always required the use of OZ Gedney "4Q" series of connectors because they last a lot longer without showing any signs of rust, than any other connector that I have tried.
 
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