ethernet cable spacing in cable tray
- Thread starter cukele
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- Location
- Logan, Utah
Take a look at 800.133(A)(1).
Chris
Chris
- Location
- Bremerton, Washington
It depends on what the wiring methods are. If the 120V controls are run in MC cable then there is no separation required.
With a divider, there is no separation required.
Article 800 is for telecommunications and I am not sure if Cat 5e falls into that article, it was 725 but something tells me it may of changed.
With a divider, there is no separation required.
Article 800 is for telecommunications and I am not sure if Cat 5e falls into that article, it was 725 but something tells me it may of changed.
What is the reasoning behind not allowing different kinds of cables like this in the same duct or cable tray?
Both are insulated well enough to contain their respective voltages. What is the hazard of having them lying among each other?
plus I see enclosures with a couple runs of panduit inside. Is something that a sufficient barrier? What constitutes a sufficient barrier?
Both are insulated well enough to contain their respective voltages. What is the hazard of having them lying among each other?
plus I see enclosures with a couple runs of panduit inside. Is something that a sufficient barrier? What constitutes a sufficient barrier?
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- Location
- Bremerton, Washington
What is the reasoning behind not allowing different kinds of cables like this in the same duct or cable tray?
Both are insulated well enough to contain their respective voltages. What is the hazard of having them lying among each other?
plus I see enclosures with a couple runs of panduit inside. Is something that a sufficient barrier? What constitutes a sufficient barrier?
Its the same reason why conductors for power and lighting can't not be in the same enclosure. box or raceway with limited energy/signaling conductor (but what about unless insulated for the same voltage-thats not what the NEC says)
Enclosures with wiring duct inside may be mfg under UL508A, which by the way does not allow a Cat 5e with power wiring, although its done all the time.
Oh sorry the hazard is if the insulation is damaged, the low voltage/limited energy equipment can be damaged by overvoltage.
Huh? If the insulation is damaged, most anything around could be damaged.
In this day and age where everything has to communicate with each other, it just seems like an unnecessary restriction without any good reason that I can see.
- Location
- Bremerton, Washington
Here is the handbook commentary on 725.136:
"Jackets of listed class 2 and 3 cables do not have sufficient construction specifications to permit them to be installed with electric light, power etc cables. Failure of the cable insulation due to a fault could lead to hazardous voltages being imposed on the class 2 or 3 circuit conductors"
I can tell you how we do it the telecom industry. Aside from the equipment manufactures like Nortel who build it into the equipment frames with a tray that looks like a heat sink with fins to segregate power, signal, ground, and telemetry.
OK if you look into Newton;s or Gray bar catalogs go to the cable rack accessory sections. Look for H, J, and L type brackets the use a clipping device to secure to the side of the cable rack with G clips.
What this will allow you to do is put up whatever size cable tray you want, and then allow you to make as many separate raceways you want. Heck Newton and ADC even make sectionalized cable trays if you want it.
OK if you look into Newton;s or Gray bar catalogs go to the cable rack accessory sections. Look for H, J, and L type brackets the use a clipping device to secure to the side of the cable rack with G clips.
What this will allow you to do is put up whatever size cable tray you want, and then allow you to make as many separate raceways you want. Heck Newton and ADC even make sectionalized cable trays if you want it.
Chapter 9 Table 11(A) Class 2 and class 3 circuits can both be 150 volts, so although I see the handbook commentary, and it certainly is not allowed, I can't see how the insulation is the limiting factor in installing them in the same duct as 120 VAC, since they could very well be 120VAC (or 150 VAC) themselves.
Just seems to me to be more arbitrary, and perhaps outdated, than anything else.
I'm not sure what you meant there.
Just seems to me to be more arbitrary, and perhaps outdated, than anything else.
I'm not sure what you meant there.
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Category cable is communications cable, and falls under Article 800 because of the definitions in 800.2.
weressl
Esteemed Member
NFPA consider fire and safety hazards, but not operational or functionality. Interference from power to signal is a problem of course and slows down signal traffic due to the continuous error corrections and croaks in the worst case.
- Location
- Massachusetts
Say you had an data line run in the same raceway as a 120 volt 20 amp circuit.
Now lets say the 120 circuit has a fault and melts into the data cable, suddenly you have 120 volts applied to the data circuit.
I have seen this happen and it was very rough all the other equipment connected to that data line.
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