LFMC Connectors

[mn_voyageur]

I was taught, and thought it was required, that the connectors could not be the lowest point.

Is my memory failing? Was a change made that I missed? Or did my journeyman just make extra work for me? (Many years ago.)

I am not asking if it is a good idea, I think it is. I made the mistake of telling one of my helpers it was required and he actually looked it up. (That will teach me to hire guys who can read.)

FB

 

[iwire]

In my opinion at least one of the connectors should be the lowest point but that rarely happens.

ARTICLE 225 Outside Branch Circuits and Feeders

225.22 Raceways on Exterior Surfaces of Buildings or Other Structures.
Raceways on exterior surfaces of buildings or other structures shall be raintight and arranged to drain.

Exception: Flexible metal conduit, where permitted in 348.12(1), shall not be required to be raintight.

 

[infinity]

Does anyone know what "arranged to drain" actually means? What did they have in mind when they put that into the code?

 

[mn_voyageur]

Arrange to drain would apply to LFMC? Is it not supposed to be sealed, when properly installed?

I read 225.22 in the handbook and understand that if the system was "raintight", you need to "arranged to drain." But does this apply to a sealed system that is completely NEMA 4X?

 

[iwire]

Arrange to drain would apply to LFMC?

Yes, if its outside and attached to building surfaces.

Is it not supposed to be sealed, when properly installed?

Yes, being raintight is actually part of the requirement

shall be raintight and arranged to drain

I have often found LFMC full of water in the low spot that is normally between the disconnect and the equipment.

 

[mn_voyageur]

Bob,

Not being aware of 225.22 ...(ignorance is bliss.)

Now that I am aware of 225.22, I understand the need to "arrange to drain" in a raintight application. Most raintight equipment is rated 3R. (If my memory is correct.) 3R equipment that I have seen, does not require gaskets or seals. (ie RNC into the bottom of the 3R panel.)

However, all NEMA 4 cabinets have a door gasket and all fittings that are rated NEMA 4 also have gaskets. Additionally, I was taught that installing a non NEMA 4 rated fitting into a NEMA 4 cabinet "derates" the cabinet to the rating of the fitting installed.

I have often found LFMC full of water in the low spot that is normally between the disconnect and the equipment.

If the disconnect and/or the equipemt was rated 3R, I can understand that water could collect at the low point. (Makes me want to take a closer look at my HVAC unit at the house.)

However, a NEMA 4 system has gaskets, unlike a 3R. Or is this a moot point?

Mark

 

[mn_voyageur]

Trevor,

Having now read 225.22, I understand the arguement to drain RAINTIGHT applications.

However, I have also seen many machines with water filled flex running without any problems.

 

[don_resqcapt19]

Mark,

If the disconnect and/or the equipemt was rated 3R, I can understand that water could collect at the low point.

You shouldn't find much water in the bottom of 3R equipment. It should have drain holes.
Don

 

[mn_voyageur]

Don,

You shouldn't find much water in the bottom of 3R equipment. It should have drain holes.

I agree. Without gaskets the 3R equipment will get some water inside and COULD collect in the attached conduit.

However, with 4/4X being gasketed, would this not prevent water entering the cabinet AND the associated condiut? (Thereby eliminating the need to drain the conduit.)

Mark

 

[paul]

If they would allow me to use set screw EMT fittings, the conduit would be arranged to drain. But no, I have to use gasketed fittings that water somehow enters the raceway, but now cannot leave. Thank you parts manufactures for fixing something that was never broken to begin with. The code has for years had the wording to arrange the raceway to drain.

 

[don_resqcapt19]

Mark,

However, with 4/4X being gasketed, would this not prevent water entering the cabinet AND the associated condiut? (Thereby eliminating the need to drain the conduit.)

I know of no conduit system installed in an outside location that will keep all water out. Often the source is condensation.
Don