Article 830

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Dennis Alwon

Dennis Alwon

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Can anyone give me a real life example of what this section is talking about. Article 830--Network-Powered BroadbandCommunications Systems.

I don't want what the book says. For instance is this the cable wire coming from the cable company?
 
Dennis Alwon said:
Can anyone give me a real life example of what this section is talking about. Article 830--Network-Powered BroadbandCommunications Systems.

I don't want what the book says. For instance is this the cable wire coming from the cable company?
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One example, practical or not, would be a cable modem that is powered by DC on the incoming cable.
A more realistic example, I think, would be cable accessories of any sort that are powered by POE or DC on the cable inserted from a local wall wart.
That might or might not count as network-powered.
 
GoldDigger said:
One example, practical or not, would be a cable modem that is powered by DC on the incoming cable.
A more realistic example, I think, would be cable accessories of any sort that are powered by POE or DC on the cable inserted from a local wall wart.
That might or might not count as network-powered.
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So this is not something you would see at a residence, correct? And what is the advantage to this system?
 
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I believe this is referencing what's called PoE, Power over Ethernet without actually saying it anywhere (probably for fear of obsolescence down the road if some other network displaces Ethernet). It might show up in residences now, because it is becoming a standard way of connecting security cameras and alarm systems. Ethernet is used for the communications from the devices to a host computer, but the Ethernet Switch puts 48VDC on the networking medium (wires) that is used to power up the cameras or sensors, using another pair of the conductors in CAT 5 cable (in most cases) for that 48VDC power circuit, however that is not always the case.

The advantage is having only the one cable run to a device, like a security camera. It's also been used for years on VoIP phones and Wireless Access Points, but those are mostly commercial and industrial so far.
Wiki article is halfway decent on this.
 
Dennis Alwon said:
So this is not something you would see at a residence, correct? And what is the advantage to this system?
Click to expand...

You often see PoE (actually Power over coax cable carrying broadband) in residential installations where power is needed for an amplifier-splitter in the attic or under the house with no nearby electrical outlet. It allows the power supply to be located at any point in the attached cables, with no separate power wiring.
And yes, I suspect that the 830 reference may be limited to power from the network side of the demarc.
 
petersonra said:
the 48V comes from a special router or switch for POE.

I don't think this article is about POE.

Among other things, I think broadband uses an analog carrier and POE is digital.

take a look at this.

https://standardscatalog.ul.com/standards/en/outline_2261
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Thank you, Jraef and GoldDigger. Since I am not familiar with these systems it is hard to figure out what these sections in Chapter 8 are talking about.

This came about because of a discussion about a hot tub being set close to the demarcation of phone and cable. Art.680.9(B)& (C) seems to talk about Art. 800 - 820 for communication & 830 for communication wire and network broadband respectively.

What is strange here is that article 90 says this.

Chapter 8 covers communications systems and is not subject
to the requirements of Chapters 1 through 7 except where the
requirements are specifically referenced in Chapter 8.
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Nowhere in 800-820 is a pool mentioned but pools are mentioned in 830 for network broadband.

Also 680.11 states (below) but this can't apply because it is not referenced in art.800-820. Art. 830 does reference 680.11

680.11 Underground Wiring Location. Underground wiring
shall be permitted where installed in rigid metal conduit, intermediate
metal conduit, rigid polyvinyl chloride conduit, reinforced
thermosetting resin conduit, or Type MC cable, suitable
for the conditions subject to that location. Underground wiring
shall not be permitted under the pool unless this wiring is
necessary to supply pool equipment permitted by this article.
Minimum cover depths shall be as given in Table 300.5 .
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