Class 1, Class 2 circuits.

[hbiss]

Exception No. 2 to (3): Limited power circuits of listed equipment where
these circuits have energy levels rated at or below the limits established
in Chapter 9, Table 11(A) and Table 11(B).

Ethernet has ZERO energy level as do many audio circuits. Though "at or below" would seem to include them.

I wonder what UL 60950-1-2011 and UL 62368-1-2014 says.

-Hal

 

[petersonra]

Ethernet has ZERO energy level as do many audio circuits. Though "at or below" would seem to include them.

I wonder what UL 60950-1-2011 and UL 62368-1-2014 says.

-Hal

It is not zero but pretty darn close. Most audio circuits (at least those driving speakers) are at least a few watts, so the energy level is much higher.

 

[Strathead]

Read carefully the part in red.

However, petersonra, I read that as circuits that are part of the listed assembly. outside what I feel we are discussing. Doesn't negate the fact that class 2 doesn't have to be identified or labeled though.

 

[paulengr]

To OPs question:

No, don’t classify it. The motor load is chapter 4 special equipment which modifies chapter 3 general wiring.

Classes 1-3 are for power limited circuits under chapter 7. Review section 90 in NEC. Chaptersi 1-3 cover general requirements. Chapters 4-6 cover special situations that modify chapters 1-3. Chapter 7 takes an entirely different approach. You IGNORE everything in chapters 1-6 unless chapter 7 specifically calls for it. As a general rule you cannot mix chapter 1-3 and chapter 7 wiring. As a general rule of thumb about the only loads you can mix are lighting loads.

Nothing OP describes falls outside general purpose wiring. It’s one thing when someone wants to run an Ethernet cable in a conduit with a couple lights. It’s quite another to be running it with power wiring and that’s what the rules capture.

 

[GoldDigger]

A literal reading of the code suggests that audio microphone or line level circuits, communicaton circuits usingl low voltages and no power wiring, and all speaker outputs regardless of power require Class 1/Chapter 3 wiring methods unless each chassis with a connector has Class 2 labelling. In some limited cases the equipment itself is powered by a wall wart or brick that has Class 2 markings, but some are powered directly by 120V AC.

 

[tom baker]

I have some sump pumps I am currently working on at a project. And plan to leave the motor starter in a common raceway with my branch circuit conductors supplying the motor, and also the 120volt control circuit conductors with OCPD, which will go to a float/switch.

From what I gather that is okay. Am I right in calling those control conductors a class1 signaling circuit?

Here is a graphic from mike holt, the control circuit can be tapped, or a class 1 remote control circuit

 

[DrSparks]

Anyone ever heard of high bay DC LED lighting wired with CAT5 cable? I looked into this when I was the plant electrician for 3 manufacturing facilities.

Sent from my BE2028 using Tapatalk

 

[hbiss]

Most audio circuits (at least those driving speakers) are at least a few watts, so the energy level is much higher.

Audio equipment and systems is Art. 640. Amplifier outputs driving speakers can supply considerable power and as such is Art 725. Also, I don't remember what article it is that prohibits even CL2 audio output wiring from sharing a conduit or raceway with other CL2 wiring.

What I'm talking about is (non phantom powered) microphone and other low level audio signals having no power involved same as Ethernet.

-Hal

 

[hbiss]

Anyone ever heard of high bay DC LED lighting wired with CAT5 cable? I looked into this when I was the plant electrician for 3 manufacturing facilities.

Sent from my BE2028 using Tapatalk

Yeah, there is somebody that pops in here every once an a while thinking that is the way of the future.

-Hal

 

[Strathead]

Attached is a handout I did for my classes that explains Class 1, 2, and3 wiring

May I purloin that PDF to use in my 2nd year apprenticeship class?

 

[Strathead]

Anyone ever heard of high bay DC LED lighting wired with CAT5 cable? I looked into this when I was the plant electrician for 3 manufacturing facilities.

Sent from my BE2028 using Tapatalk

Until recently I hadn't run in to "power over ethernet" light fixtures. Now I have, and I feel that is a misnomer. It is merely power over a cable and connectors that are also used in ethernet applications. It has zero to do with ethernet.

 

[tom baker]

May I purloin that PDF to use in my 2nd year apprenticeship class?

Sure it’s several code cycles old

 

[DrSparks]

Until recently I hadn't run in to "power over ethernet" light fixtures. Now I have, and I feel that is a misnomer. It is merely power over a cable and connectors that are also used in ethernet applications. It has zero to do with ethernet.

No it's not POE. It just uses the cable. Actually 2 cables in parallel.

Sent from my BE2028 using Tapatalk

 

[DrSparks]

Yeah, there is somebody that pops in here every once an a while thinking that is the way of the future.

-Hal

It is. It is the way. You must conform.

Sent from my BE2028 using Tapatalk

 

[petersonra]

Yeah, there is somebody that pops in here every once an a while thinking that is the way of the future.

-Hal

Low energy cabling has the potential to change a lot of things, but until we get over the mindset that somehow conduit is a high quality installation and cable is a hack job, we probably won't get there.

 

[don_resqcapt19]

Read carefully the part in red.

that tells me they are still listed to supply class 2 rated power

 

[hbiss]

Low energy cabling has the potential to change a lot of things, but until we get over the mindset that somehow conduit is a high quality installation and cable is a hack job, we probably won't get there.

I don't think that's what it's all about. The push is for higher and higher power which at low voltages obviously has negative consequences. Actually it's about shifting the work to other than the electrical trade.

-Hal

 

[petersonra]

. Actually it's about shifting the work to other than the electrical trade.

-Hal

Which is probably a good thing for most people, not so much for electricians. But we shouldn't be making these kinds of decisions based on who's going to profit from it.

 

[Jraef]

Anyone ever heard of high bay DC LED lighting wired with CAT5 cable? I looked into this when I was the plant electrician for 3 manufacturing facilities.

Sent from my BE2028 using Tapatalk

I find that a bit far fetched. While technically CAT5 is rated 300V, 22ga would make it good for about .7A in a multi-core cable. So assuming 277V max., that's less than 200W and even with LED, I don't think a 200W fixture would be much of a "high bay" light source. I also don't think you would find an AHJ that would allow it to be used for 277V, or even 120V for that matter. If they were thinking 48VDC to make is "low voltage", the current is the same, so now we are talking a 33W LED fixture...

 

[tom baker]

I updated the Understanding Art 725 table its based on the 2005 NEC and not sure what has changed since then

Sure it’s several code cycles old

See this one