Im in search for advice on whether or not the current EIA\TIA standards for commercial low voltage cabling states that conduit (EMT),or some type of mechanical protection is recommended or required for cabling installed in industrial,and warehouse environments.One example im facing:Getting cabling dropped from a 25'warehouse ceiling to a work station desk below.Example 2:From the same ceiling,into a warehouse office.Example 3:Cable drops down pillars to the work area.Ive been having the facilities electrician install EMT for this stuff.Am I on the right track?Unfortunatly I have no access to the current standards right now.Thanks.
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Conduit or not?
- Thread starter rpearson
- Start date
jeffbouldin
Technical User
From my understanding, low voltage only needs to be in conduit seven foot from the floor. However in a warehouse I would have it in conduit anywhere it is possible to be damaged by people or machinery(forklifts, stacking product on shelves, etc.). If you want to run the wire through the rafters and have conduit come down the wall from the ceiling you would be safe.
- Thread starter
- #3
I agree, thats the approach Ive been taking.However,im seeking a specific industry specification or standard if any.What I failed to mention is our electrician has challenged the idea of running conduit, specifically EMT,for my cabling,but he is not against it by any means.I would just like to prove my point of the protection of cabling in this environment to him.Thanks.
You might try another approach besides the obvious fact
that it offers protection.
If for some reason the cable has to be replaced, how much time is going to have to be spent removing the old and installing a new one in its place?
Its pretty quick and easy if its running in conduit.
that it offers protection.
If for some reason the cable has to be replaced, how much time is going to have to be spent removing the old and installing a new one in its place?
Its pretty quick and easy if its running in conduit.
I agree with jeffbouldin there are many reasons to protect your cabling in this environment. I wired a manufacturing floor a couple years ago. We used kellum grips attached to bridal rings, to hold about 40' of Greenfield(flex) attached to a metal box. This paticular plant changes around quit a bit so when they do you pull up the flex and move it to the new location. We ran 25 pair power-sum cable from the Closet to the floor. New lines were installed from these(zone cabling if you will). Your cable guys can install the flex and your electrician can does not have to worry about EMT
.
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We use both flex and EMT depending on the situation. EMT is cheaper and easier when we can place the drop at a column, however when using flex we can hang it anywhere we like on the shop floor.
We have only used EMT to enclose the horizontal portion of the cable runs on one occasion. A nice way to do it except that the cost is generally more than what my customers want to pay and it does very little enhance the reliability of the cable runs.
We typically install a 10' EMT stub at the drop location with the box located about 4' above the floor. This usually gives the cable adequate protection at a reasonable cost to the client
We have only used EMT to enclose the horizontal portion of the cable runs on one occasion. A nice way to do it except that the cost is generally more than what my customers want to pay and it does very little enhance the reliability of the cable runs.
We typically install a 10' EMT stub at the drop location with the box located about 4' above the floor. This usually gives the cable adequate protection at a reasonable cost to the client
Daron
"I don't see where communications wiring is required to be installed in conduit below 7'"
Good
"The BICSI TDMM 9th edition chapter 4 Horizontal Distribution Systems identifies Flexible conduit unsuitable for use in buildings. "
You just said it did not have to be in conduit so what is it in? Can you have exposed wire?
Is BICSI a governing body over anything?
"I don't see where communications wiring is required to be installed in conduit below 7'"
Good
"The BICSI TDMM 9th edition chapter 4 Horizontal Distribution Systems identifies Flexible conduit unsuitable for use in buildings. "
You just said it did not have to be in conduit so what is it in? Can you have exposed wire?
Is BICSI a governing body over anything?
daronwilson
Vendor
As I said, I don't see any requirement for protection from physical damage except for fire alarm wiring. However, if you have any wire exposed below 8 feet (maybe 7, don't remember) it is required to be secured every 18".
With regards to BICSI, no they are not a governing body. However they do produce a very nice book for designers and installers based on the EIA/TIA standards. Their point in this portion was not to plan installations where you have runs of flex conduit. If you are going to use conduit (required by las vegas for ALL wiring for example) for whatever reason, you should not be using flex unless there is no other way to route a standard raceway.
While the EIA/TIA standards are 'voluntary', some states (Washington for one) have adopted the entire set of standards as law for cabling installations. I was shocked to see it, but when I called and asked they confirmed that any installation in Washington better be compliant with the EIA/TIA standards for telecommunications wiring. I find the BICSI reference much easier to read and research than the actual standards, plus it has lots of illustrations and tips.
We find it often in commercial building that the specifications are conduit in the wall, stubbed up above a suspended ceiling. In those cases, you would want to use EMT not flex conduit unless necessary, that was my point.
Oddly enough I have the same 24 hours on my hands that the rest of you do.
Keep up the good work!
It is only my opinion, based on my experience and education...I am always willing to learn, educate me!
Daron J. Wilson, RCDD
daron.wilson@lhmorris.com
With regards to BICSI, no they are not a governing body. However they do produce a very nice book for designers and installers based on the EIA/TIA standards. Their point in this portion was not to plan installations where you have runs of flex conduit. If you are going to use conduit (required by las vegas for ALL wiring for example) for whatever reason, you should not be using flex unless there is no other way to route a standard raceway.
While the EIA/TIA standards are 'voluntary', some states (Washington for one) have adopted the entire set of standards as law for cabling installations. I was shocked to see it, but when I called and asked they confirmed that any installation in Washington better be compliant with the EIA/TIA standards for telecommunications wiring. I find the BICSI reference much easier to read and research than the actual standards, plus it has lots of illustrations and tips.
We find it often in commercial building that the specifications are conduit in the wall, stubbed up above a suspended ceiling. In those cases, you would want to use EMT not flex conduit unless necessary, that was my point.
Oddly enough I have the same 24 hours on my hands that the rest of you do.
Keep up the good work!
It is only my opinion, based on my experience and education...I am always willing to learn, educate me!
Daron J. Wilson, RCDD
daron.wilson@lhmorris.com
daronwilson
Vendor
Ahh, the 'AHJ' (Authority Having Jurisdiction). It is always interesting to me to see how other areas deal with it. Here we have a State Building Codes Division, the state has adopted the National Electrcial Code, and then written their own addendums to it in a few areas. Local jurisdictions again have their own tighter regulations. Portland for example has a complete additional set of rules that must be adhered to in that area. Not to be outdone, the Fire Marshal in each jurisdiction has authority with the Fire and Life Safety Code AFTER the building is occupied. Life Safety concerns can honestly be grossly missed in the construction phase, and if he wants to, the Fire Marshal can seriously mess up your day if he doesnt allow you to use the building for it's intended purpose when complete.
We don't use plenum wire unless we put the wire in a plenum space. Very few of the facilities we work in have wiring in plenum spaces. Oddly enough, some facilities fall under the Oregon Specialty Code (health care, schools, etc) and may require plenum wire, but it is up to the AHJ. I usually call the inspector prior to bidding if I am unsure and explain the situation, since he is the one that will pass or not pass the installation.
When we do a fire detection system, my first trip is to the Fire Marshal with a set of plans and make sure it meets his needs. Often he adds a few devices, moves things, changes a few locations, etc. I incorporate his changes into the plan, and generally that makes him happy with the installation.
Always the best, in my opinion, to go to the AHJ and get the latest codes you will need to comply with prior to starting the installation. This may include building inspectors, electrical inspectors, fire marshal, etc.
Good Luck! It is only my opinion, based on my experience and education...I am always willing to learn, educate me!
Daron J. Wilson, RCDD
daron.wilson@lhmorris.com
We don't use plenum wire unless we put the wire in a plenum space. Very few of the facilities we work in have wiring in plenum spaces. Oddly enough, some facilities fall under the Oregon Specialty Code (health care, schools, etc) and may require plenum wire, but it is up to the AHJ. I usually call the inspector prior to bidding if I am unsure and explain the situation, since he is the one that will pass or not pass the installation.
When we do a fire detection system, my first trip is to the Fire Marshal with a set of plans and make sure it meets his needs. Often he adds a few devices, moves things, changes a few locations, etc. I incorporate his changes into the plan, and generally that makes him happy with the installation.
Always the best, in my opinion, to go to the AHJ and get the latest codes you will need to comply with prior to starting the installation. This may include building inspectors, electrical inspectors, fire marshal, etc.
Good Luck! It is only my opinion, based on my experience and education...I am always willing to learn, educate me!
Daron J. Wilson, RCDD
daron.wilson@lhmorris.com
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