AC/DC power supply in plenum—this can't be legal, right?

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PetesGuide

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Foster City, CA, USA; NEC 2014
I'm doing a Wi-Fi AP installation, and in routing the cables to one location, I came across these items, which rather horrified me, but I'm having difficulty finding anything in the code that prohibits anything about the power supply aside from the flexible cord that is part of the equipment. What am I missing?

GooseneckLamp.jpgPowerSupply.jpg

I got the facilities manager, and he was horrified; removed the lamp, but wasn't sure about what the power supply was, so I looked at it and found it to be an Astron RS-35M, which turns out to be a power supply that is rated for 12VDC at 25A continuous duty/35A peak. No indication from the specs that it's got UL 2043 approval. And the red/black cable does not appear to be plenum rated, and dips down inside a nearby wall, terminating in DC outlets.

The facilities manager and I are looking for everything we can use to back up our desire to remove the power supply, and prohibit anything similar in the future.

(The lamp was apparently there as a semi-permanent work light to support accessing the DC power and coaxial cables supporting multiple two-way radios in the room below.)

All references to NEC 2011.

The power supply has a metal enclosure, but that's not enough to make it permitted under 300.22(C)(3) or isit?? And 400.7 prohibits this. And 400.8(5) doesn't apply here, right? Is there anything about non-listed heat-generating devices in plenum spaces? What about the exposed DC connections? I've never had to deal with section 450 before, but this is a transformer, so does that give us any leverage?
 
If 12 VDC is no longer needed, just take it out. I guess my question would be what is the reason to leave it there?

If it is still needed, re-locate because:

1) Power switch and meters not readily accessible.

2) If there is a hazardous malfunction with the power supply, it won't be noticed.

3) Both the 120 cord and the 12 volt conductors could be considered flexible cable.

4) Is the 12 volt cable a Chapter 3 method? The 12 volt cable used in my radio station is not. But, my radios are sitting on a desk, not part of a permanent installation hidden above a ceiling and running through a wall.

5) Since the Astron power supplies are used mainly by amateur radio operators, there is a good chance that there is no UL listing. Astrons aren't the greatest, but at least they are decent quality, name brand units.

6) It's just stupid. I've been a licensed ham for over 20 years and I would call putting a PS above a ceiling, especially a plenum, just plain stupid.

Now, remember, the NEC is a BARE MINIMUM STANDARD. It doesn't address every stupid installation on the planet.
 
Another issue is that in an earthquake the power supply would fly around and could land on someone.
Where I work we have an Emergency Ops Center, using the same type of power supply. They sit on a desk and are fastened down.
Just because its 'low voltage" does not make it safe. if (and it does) the power supply power exceeds that of a Art 725 Class 2 system (100 VA) then it requires a chapter 3 wiring method, IE MC cable, EMT, etc
If the suspended ceiling is an air handling space, that equipment can 't be there.
 
It's plenum

It's plenum

The ceiling is plenum, 100% for sure. I believe those two diffusers go to different rooms.

K8MHZ, it's indeed powering amateur gear, so removing it will require providing an alternative. All of your points sound reasonable. Can you point me to articles and paragraphs that support them? I need to dot my i's and cross my t's here.

Tom, WRT "If the suspended ceiling is an air handling space, that equipment can 't be there.", can you also point me to the right citation? I know the cords can't be there, but the equipment has a metal case, and the wording relating to that is going to give the guy who did this some wiggle room unless I can connect all the dots.
 
PetesGuide said:
The ceiling is plenum, 100% for sure. I believe those two diffusers go to different rooms.

K8MHZ, it's indeed powering amateur gear, so removing it will require providing an alternative. All of your points sound reasonable. Can you point me to articles and paragraphs that support them? I need to dot my i's and cross my t's here.

Tom, WRT "If the suspended ceiling is an air handling space, that equipment can 't be there.", can you also point me to the right citation? I know the cords can't be there, but the equipment has a metal case, and the wording relating to that is going to give the guy who did this some wiggle room unless I can connect all the dots.
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Have you tried asking the ham radio operator if he would move the PS? Most hams I know are pretty reasonable people. Asking him or her to move the PS may get cooperation, where trying to use 'force' may not.

One question I have is the space the PS is in owned or rented by the amateur radio operator? If it's owned, there isn't much you can really do as far as trying to force compliance.

That being said, and with only a 2008 NEC nearby, I think this would apply:

For the 12 volt conductors:

310.11 requires markings
310.13 outlines allowed conductor types based upon table 310.13(A)
300.3(A) disallows individual conductors. (Conductors must be in a raceway or be part of a cable, basically)

So, that means the 12 volt conductors in the wall, unless in conduit or part of a cable, are a violation.

Is there a panel arranged and secured to allow access to the equipment? If not, that would be a 300.23 violation.

Nonetheless, a simple request may get you more results than a confrontation.
 
As for the 120 volt cord that is part of the power supply, many will argue that 400.7 does not apply, as the cord is a power cord, not a flexible cord.

MH had a big discussion about this. There is a video about it around here somewhere.

A far bigger issue is the 12 volt conductors going through the walls. To me, anyway.
 
The ham in question does not own the building, but is somewhat in control of this particular room, and is not a reasonable one.

None of the reasonable arguments presented here will convince him (based on past experience), and those with authority over him are also difficult to persuade (and have given him wide leeway in the past; poking holes in the roof with antennas has not diminished his ability to do unsafe things), so I need to have as many solid references as possible before this gets presented to the right people.

I'll look at 310.11, 310.13, 300.3(A), and 300.23 when I get home, but all sound reasonable, and will help greatly!
 
PetesGuide said:
The ham in question does not own the building, but is somewhat in control of this particular room, and is not a reasonable one.

None of the reasonable arguments presented here will convince him (based on past experience), and those with authority over him are also difficult to persuade (and have given him wide leeway in the past; poking holes in the roof with antennas has not diminished his ability to do unsafe things), so I need to have as many solid references as possible before this gets presented to the right people.

I'll look at 310.11, 310.13, 300.3(A), and 300.23 when I get home, but all sound reasonable, and will help greatly!
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Well, as far as I know, it's the owner of the building's ultimate responsibility to comply with enforced codes, not the tenant's. If the owner of the building wants to allow code violations, there isn't much someone in your position can do about it.

I'll bet if you look at Article 810 closely, you are likely to find more violations. I suspect that because almost none of the hams I know could say they don't violate any of Chapter 8's requirements.

Start at 810.51 and have a field day.

Then take a look at 810.70 and it's spacing requirements.

The owner of the building can also request the local AHJ to come in and take a look as well. Ours will gladly come out and look at stuff, answer questions and provide code references. Sometimes, even in writing.

Have you considered that?
 
I just took another look at the pictures.

Do I see violations there not related to the Antron unit? Like unsupported cables?

After review, a couple things come to mind.

Glass houses and Pandora's Box.

Proceed with caution. I know your intentions are good.
 
Marky--thanks for all of your answers!

About asking for the AHJ to come in, that may be an option, but there are other parts of this company that will respond in a reasonable manner, I just have to paint a thorough picture and teach them a little bit here and there.
 
PetesGuide said:
Marky--thanks for all of your answers!

About asking for the AHJ to come in, that may be an option, but there are other parts of this company that will respond in a reasonable manner, I just have to paint a thorough picture and teach them a little bit here and there.
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Just gently let them know that if the power supply fails the smoke it lets out will be spread through the whole building automatically.
So it affects more than just the radioman's room.
 
tom baker said:
Another issue is that in an earthquake the power supply would fly around and could land on someone.
Where I work we have an Emergency Ops Center, using the same type of power supply. They sit on a desk and are fastened down.
Just because its 'low voltage" does not make it safe. if (and it does) the power supply power exceeds that of a Art 725 Class 2 system (100 VA) then it requires a chapter 3 wiring method, IE MC cable, EMT, etc
If the suspended ceiling is an air handling space, that equipment can 't be there.
Click to expand...

I'm trying to determine if this falls in Chapter 3. The power supply can put out 35 Amps at 12VDC, but I can't find any ratings on the device or spec sheet for how many amps it draws from the AC socket. My calcs say no, but I'm not quite sure I've got the equation right.
 
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