On several sites, I've read posts by people asking for/suggestion for standardized DC wiring in a building. Currently, people who want a DC-only residence (or even a separate DC bus in addition to AC) must manage every wire in a system, connecting them with solder or wire connectors. This is not a sustainable (pun a bit intended) option for increasing alternative energy use or advancing alternative energy technology. Most people do not want to design and wire a complex electrical system and manufacturers are limited to the customer group that is at lease comfortable with electrical.
Technology and progress aside, using a standardized connector in a home is more aesthetically pleasing. Likewise, it affords the ability to plug in appliances in different parts of the house. Which is nice.
So, has anyone researched power over ethernet (PoE)? It's just what it sounds like, adding power to an ethernet cable such that devices on the end of it can be run from said power. It has been standardized (IEEE 802.3af) and there is a wide availability of devices capable of "injecting" power into the wires.
The IEEE 802.3af standard specifies injectors must be able to provide 0–12.95 watts (per cable) and there are multitudes of DC appliances that operate within this range.
Here's an example of a switch that can power devices via
A company that sells crazy configurable LED lights that are powered by PoE and have an integrated system on them that makes them part of the network. They teamed with with Cisco (who now makes a PoE injector capable of injecting up to 60watts) and made this presentation:
So yeah, how does it sound to you guys. I'm a few months away from starting to build my new house and this is a serious contender on how I light it (house will be on solar power).
Garrison, im all over this one too. Its coming, telecom, data facilities, and automation, commercial and industrial lighting with smart sensors and control.
48v and 150w maximum powered-loads circuits on network switches will be a great way to distribute power and smarts as soon as thats all hashed out code and listing wise.
Of course, for my use, i dont want many smart features and the loads that i run at our off grid home are so low that i could power all area lighting on two cat6 cables.
With a POE distribution system data and power to most any point in the home is inexpensive and easy to plug and play.
The power limitation (tiny conductors) is the major issue many will have with a straight POE home. Mainly us people who have no loads outside that limit will see immediately the utility because in my case there just is no need for more outside my workshop/garage which happens to be where the inverter is located!
I have not looked at progress or dug too much deeper than tech briefs and lighting modules for commercial lighting retrofits in a while.
Please read my comments, i have been trying to spread it around because at least for lighting and smart home automation, this is here.
Now when poe and ac are run together everywhere conventional ac outlets are during a new build, the best of both can be utilized and meet code.
One idea i have for this is to eliminate ac power entirely from my living space. I dont like it, puresine inverters have better waveform than utility power but also usually emit radio interference and it can travel on and radiate from your wires. I think this damages people and have at least put all ac wiring in our quite tall ceilings and did not run any wiring at places along walls where people linger. Most peoples couches and beds are right up against the circuits in the wall carrying power.
We use switches and wiring to shut off power in the wall between our bedroom and the bath, so that our heads are not at that sweetspot against the wiring for 8 plus hours a night. Outlets off, lights out.
With poe i may dodge entirely having to operate switch-gear in my bedroom!
Not that complicated two switches though so budget matters.
If we had a larger family this would be impractical and automation of the scheme would be slick.
Mains panels and control panels for home automation are already available.
This is sweet because the system can connect ac lines as i need them without my manual operation and the power can be switched right in the mains panel.
Additionally, many off grid and back up power inverter systems are network devices, already are incorporating modbus relay control and have programable logic...!
If you use the logic and flat-line your house static and disharmonious and "dumb" power. The result can be harm reduction and high efficiencies and awareness within the system. The thing i will not do is connect my system to the internet, ill maintain an intranet here.
Being in close proximity to em fields and rfi from utility power and powered devices is implicated as a cause of leukemia and other debilitating effects that i think are so low lying that it is never co-related in our minds that its just a no-no.
I thought electrical equipment met certain standards (and was tested) for eliminating RFI. Metal case shielding, inductors on conductor in/out of the case, etc. That doesn't get rid of the 60Hz fields, but it should reduce RF to a very low level.
I haven't looked at the field strength of RF in urban areas lately. Suspect it might be a bit mind boggling, but don't have any hard data.
posted 4 years ago
Rufus, i saw some interesting info about how lax us standards are for this and they illustrated how in other countries, the equipment is designed and mandated to provide meaningful* protection.
Heating blankets, lighting ballasts, transformers, they said, were arranged to help bind emf for health protection.
And most equipment should not interfere with other peoples equipment.
In the case of the wireless access point, approximately 201 milliwatts of power were dissipated on the Category 5e circuit and approximately 137 milliwatts on the Category 6A circuit.
In the paper's conclusion, Gould states, "With the world's ever-growing demand for energy, finding new and more-efficient ways to deliver it is essential. PoE not only decreases infrastructure material, when run over Cat 6A, it delivers power more efficiently. For customers seeking high efficiency and future growth potential with their networks, once choice for PoE stands above the rest - Cat 6A cable."
Location: Chicago/San Francisco
posted 4 years ago
Thanks for those links. I check them out tomorrow. Although I'm sure our electrical emissions environment has increased hugely in 100 years, I haven't seen general consideration (aside from frying in high power microwaves) of health consequences.
I don't get it. How is installing Cat-5 cables any easier than installing DC wiring?
The main difference is that Cat-5 uses very thin wires so it's going to be less efficient than what you'd get if you ran DC wires specifically for the application.
The rules for DC wiring is already specified in the National Electric Code. I wired my workshop up with 120V AC as well as 12VDC and 24VDC outlets and did it following the NEC rules. I had to educate the inspector on the NEC rules for DC wiring, but other than that I had no problem getting it approved.
FWIW NEC rules allow you to use AC outlets for DC outlets, you just have to use different style outlets for each so that you can't accidentally plug a DC appliance into an AC outlet, etc. In my case I used twist lock outlets for the DC wiring, right hand twist for 12VDC and left hand twist for 24VDC.
My opinions are barely worth the paper they are written on here, but hopefully they can spark some new ideas, or at least a different train of thought
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