I think the one thing that makes AC such a wonderful invention, is the induction motor.
Man, what a pleasure. No brushes or rings. It is essentially a transformer with a spinning secondary.
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Second PoE as massively under-utilised for power.
Formal specification provide for up to 100W over 4 wires which is a heck of a lot of power.
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Distance, volts?
Yeah like “someone” (@plonkster), not mentioning names, said - my words - Google much … but the amount of damn info is getting tiresome to thread through to the salient core data.
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Just to clarify the up too 100W for any future readers, there are some limits to this.
Don’t put your own 12V 8A power on those small ethernet wires. It’s only up to 960mA per pair.
Some high level details on the specification:
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Yeah as I understand it, it’s 960mA at 48V over TWO pairs (to give it enough copper). That get’s you just a tad over 90W.
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I read a comment by someone in Gordons Bay doing power reticulation over PoE. I can’t find the thread now…
That was probably me (thread is over on “that other forum”).
Work from home programmer, with solar setup that currently has no inverter.
I run my computers off 48v DC, monitors are at 19V DC, the rest of my network etc. equipment is all powered over PoE and running at 48v.
For my new house (which I finally moved into 2 months back) I wanted to take that a step further and power all lighting over PoE, but due to having too many other building issues to deal with, and the electrician my builder appointed not being the brightest, and also due to PoE lighting not being that readily available in za yet (I still predict it will be a huge thing going forward - but in corporate space before homes obviously) I temporarily let that one go, so my lights are just running off grid.
I’ll probably switch them over slowly over time though, for now I might get a small inverter just for lights as a quick solution to get lighting on the solar.
Well theres the radlok connectors that pylontech use for their batteries, those are fantastic, but a bit pricey…
Theres the xt60 connectors (used a lot in robotic type stuff, model helicopters etc.) which are also quite widespread/common - these are cheap.
For now I’ve “standardised” on radlok for any high voltage/high current stuff.
xt60 for my 48v stuff (like computers)
anderson for 12v stuff (because its easy to get a cheap distribution block for it like this - https://i.pinimg.com/originals/79/f2/3c/79f23cd62ca156bb986c9e91e43dc985.jpg; but I don’t like it for higher voltage stuff)
But try to prefer PoE/usb where possible.
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It is also worth remembering that thats 90W over 100M, in reality (especially for households) you can get away with cable runs much much shorter than that, its rare to have a 100M long ethernet cable in a regular home (I would think).
Also specced for CAT5 cables, while I believe CAT6 can handle a bit more, and I believe you can get some “special” ethernet cables on the market that are specifically thicker than spec for extra PD as well.
Which is not to say that I’m recommending pushing more than 90W, but rather that its unlikely to be as close to the upper limits of the cable as one might think on first glance at the specs.
90W is actually an incredibly useful number these days, a lot more household things (most light fittings; pretty much all alarms/sensors/electronics for instance) that can run on 90W then there were in previous years.
Fascinating! Are you using laptop computers or computers with plug-in bricks?
Did you mod the screens to bypass the AC side?
I presume the LAN cables aren’t being used as such?
Are the RJ45 plugs the standard plugs used?
I’ve been impressed with these plugs: Well thought out with their recessed contacts.
And since there are so many network installers one can get this done fairly easily…
I have noticed that CATx cable is thrown away regularly (not even enough copper to warrant stripping the insulation)
Standard desktop machines, but using 48v DC power supplies instead of the standard AC PSU’s that most have. High efficiency second hand 48v server power supplies can be had cheap off ebay.
I happened to be on the market for better monitors when I first started toying with getting some panels.
So I specifically went for LG IPS monitors that come with external power bricks, they run DC internally and the bricks provide 19v to them (external bricks for monitors with DC internals seems to be a growing trend for monitors as well)
So I just don’t use the bricks and feed them the 19V directly instead.
Everything I currently use PoE for also carries LAN data as well, as its all networking equipment as well.
For 48v non data (and higher current) stuff, like the desktop machine I use xt60 connectors for now.
Though I do run 2x network cables to each desktop machine for data anyway, they draw more than 200W (so even using the 2x cables both for power the standard would still fall short) but its tempting to try power them via multiple PoE cables or something, it would be neater. I might revisit that idea at some point.
If there was anything that needed lower wattage 48v but no data I guess I might consider PoE anyway, just for the sake of standardisation, but I don’t currently have anything that fits that description (Turns out most important things in our life need both power and data now).
For the lighting if/when I do it then that too will have LAN capacity as well, because its all smart lights/switches then as well, I guess a lot of that could use wireless for the data, but if you’re running cables may as well use them for both, PoE is nice that way.
Just standard plugs yeah.
I presume the light fittings are bundled with the PoE offering?
Post a link to one of these vendors so we can check it out…
So a basic example is https://unifi-led.ui.com/ (both light and switch); With this sort of thing its all bundled as one. Its possible of course (and there exist devices) that combine with a regular “dumb light” as well.
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How about commandeering those silly 5A plugs & sockets https://www.acdc.co.za/products/5a-3-pin-socket-flush-mount-round?variant=30468492940
Do I have any takers??
Herewith an article on DC microgrids By Igor:
Direct Current (DC) technology is quickly disrupting the traditional alternating current (AC) line voltage markets and DC microgrids are becoming the power source of the future. Typical AC alternates back and forth sixty times a second, similar to ocean wave energy pulling and pushing a boat up and down, whereas DC is energy constantly streaming in one direction similar to a flowing river. Most digital devices (e.g. cell phones, solar panels) are natively DC, and extra work is required to adapt them to AC line voltage. Additionally, each AC/DC or DC/AC conversion causes approximately ten percent power efficiency loss. For example, solar panels generate DC power which is converted to AC, and then converted to DC again at a typical digital device. This efficiency loss represents a significant cost for companies.
Also, when running at a lower voltage as does Power-over-Ethernet (PoE), a DC distribution system more efficiently delivers power to end devices. This energy efficiency leads to cost savings for companies, making the system a strong alternative to traditional line voltage. Customers are demanding businesses practices align with ESG (environmental, social, and governance, and DC microgrid power savings will have a meter-moving impact considering buildings use 40% of our energy and 70% of our electricity. DC microgrids will be the up-and-coming solution for organizations in 2021 to meet their sustainability goals.
Additionally, true low voltage DC technology also provides significant safety advantages as recognized by the NEC’s (National Electrical Code) class-2 electrical designation. Class-2 devices nearly eliminate risks of electrocution and fire; low voltage installs do not require electricians nor conduit or other highly rated equipment.
When using Power-over-Ethernet for a DC microgrid, installs benefit from plug-and-play modularity, flexibility, and component miniaturization. From hospitals patient rooms to large open office spaces, these benefits deliver lower initial costs and transform spaces into agile environments that economically change over time.
Power-over-Ethernet (PoE) makes microgrids more intelligent and effective. PoE delivers low-voltage DC power and IP data simultaneously over a single Ethernet cable. PoE eliminates the numerous conversions between AC and DC, reducing energy losses. PoE can cyber-secure, power, and connect a wide variety of devices with the DC microgrid including lighting, environmental, access control, safety, sensors, and many more niche applications. PoE in combination with an intelligent controls software, like Igor’s Nexos IoT Platform, optimizes building systems through data and provides a single point of control. Armed with this information, building management can make smarter, more sustainable, and secure building decisions.
The DC microgrids will revolutionize the way the world is powered. DC microgrids reduce risks and costs while simultaneously improving safety, security, and sustainability. Power-over-Ethernet with Igor-Enabled intelligence is the clear choice for DC microgrids to additionally provide intelligent management and protect each end device with cyber-security.
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Post the link please…
See the link ‘10 percent efficiency loss’