The day came when it was time to test it out. All the Ethernet lights came on, but throughput was on the order of less than a few kbps. I let the project manager know that something was wrong with the cabling.
He got back to me a week later. The electrician who ran the line ran out mid way and used wire nuts to splice another length of cable. The fix was to simply terminate each end correctly on a splice connector. IIRC they might have even just re-ran one single length.
But the instinct not to trust electricians to run CAT5/6 was 101% correct!
Electricians also almost always use the wrong colors when wiring speakers with something like a 16/4. I have ran into this a lot.
When I went to do low voltage later I realized what he meant. Stereo and security installations just isn’t something you want your electrician, whose knowledge mostly revolves around huge, 1000+ amp panels, to be doing. There’s way more money in commercial installs, so most electricians only do residential work to tide them over.
My dad doesn’t even want to terminate anything more complicated than 4 conductor phone wire, and would pull me into a job just for that reason.
What happens if you somewhat exceed the 100m limit? The only sources I can find boil down to just don't do that but I can't find a chart showing what happens to performance/frame loss.
Would it help to have a heavily shielded cable?
It depends on your system. If you're running old school shared medium Ethernet (with hubs, not switches, for cat5), or even just half-duplex mode, if your run length is too long, the big issue is that you've lost guarantees about collision detection; in that case, receivers may see collisions that senders don't, and you're left with transport layer resends (if any) instead of Ethernet layer resends. This is because of transmission speed, minimum packet lengths, and the length of the cable mean that one sender could finish transmission before seeing the second sender's preamble.
If you're running full-duplex dedicated medium, collision detection is a non-issue, there are no collisions. GigE transmits and receives on all four pairs simultaneously and uses echo cancellation to remove the echo'd send that comes back from the far end, the extra distance will make the echo come back later than expected, and that might be outside the ability of the network cards' signal processing to adjust.
Assuming that's not a problem, you would have more resistance, and probably more? capacitance, which may make signal recovery more challenging. 100BaseTx would probably be more likely to work than GigE, in my opinion, but I'd certainly try both. Ethernet autonegotiation runs on a single pair at 1Mbps, so it's quite possible that the cards will negotiate to 1G, and then not be able to actually communicate at that speed because of the wiring parameters.
One important thing to consider is that Ethernet wiring specifications are such that minimum standard wiring will work at a very low error rate at maximum length when in a bundle with many other ethernet cables/other low voltage signaling cables. If you don't have a lot of bundled cables, you have a bit more wiggle room. Of course, if you run the wires parallel and close to AC wires, you have a lot less wiggle room.
It would certainly make network engineers cry, but you have to work with the site and wiring you have, and only sometimes is it easy or convenient to run new cabling.
That is, at least, what was described to me in Computer Networks I back in 2006. I'm sure things have changed as we've moved to always using full-duplex wiring and fully-switched networks.
At work we had to repurpose a pair 170ish meter cat 6 cables for some cameras and it has worked nicely for three years (with PoE even). We tried again with a 100m cable rated for exterior (plus female + patch cords) and it wouldn't even link at 100mbps
I have all lights (100+) in the house on Zigbee but without changing any wiring. Only non standard is that I replaced all the wall switches with a variant that's electrically "always on" and sends a Zigbee command when pressed (and can be pulled out to access a traditional physical switch as a backup in case of full system failure). They fit the original Siemens outer wall plates that my house was built with so everything looks standard. Returning evening to non-smart in case I want to sell the place is an afternoon of work replacing the switches behind the plastic face plate with their old versions. Those are all in a box in the attic :-)
The benefits of smart lights for comfort are pretty big, auto-on lights by motion detection is great for bathrooms, storage rooms etc. Having the color temperature match outside and time of day is also much better than traditional dimmers. Voice control is useful in some situations (mostly when cooking or carrying kids or groceries). And being able to walk out the front door saying "Alexa, turn off all lights" is a great way to save energy and make things easy.
At the moment I have standalone lamps with Sonoff D1 dimmer and halogen (yes, really) bulbs that can actually be dimmed 0-100%.
It is insane how unreliable the ikea products have been and how terrible the interface is vs philips.
I am moving to Deconz (Phoscon) for full flexibility though..
Your house is massive or your castle is very tiny. Either way, that’s an usual amount of lightbulbs.
I have some bulbs, 4 spot lights, lightstrips around the living room. Lamps around the studio, bedrooms, living room. If you add bias lighting and indirect light by bouncing off the ceiling you add up quite fast.
Granted, I built up this setup over some time, finding the best use for each set of lights I got but I can definitely see how you could get up to 100+ in a larger house.
Even a bathroom easily has 6 or 8 in the ceiling, a few near the mirror etc.
https://www.lutron.com/en-US/products/pages/standalonecontro...
Made for UK wall switches.
Everything is controlled via Homeassistant+Deconz and a Phoscon Zigbee Dongle.
It's even possible to hack the IKEA switches into the danish wall switches.
Still wondering what @t0mas88 is using...
The upcoming Lidl remote is very interesting indeed, because it has 4 buttons which could be wired to a regular 2 button up/down push switch (e.g. Gira 014700) as cheaper friends of hue alternative.
Also 3d printed a holder for a few places that slots into a Gira frame and holds the Philips Hue Tap button. Allows more control of scenes etc, but the color isn't exactly the same.
Friends of Hue (Gira and others) with EnOcean comes close, but you'll typically bridge the switch AC wires, so there is nothing to pull out and manually control things as backup.
And 3d printed a holder for a few rooms that fits the Gira frame and holds a Hue button. Works to control more things (and used it that way in my old house), but the color of Hue isn't exactly the same as the frame.
If they were held in by magnets then I'd call them the perfect switch for the Hue series.
Unfortunately they discontinued them, and on the used market they're often >$100 per switch.
Can you explain what the problem is? I also run cat5 (or maybe even cat6, don't remember) to every room, most even multiple times, just put it in walls/cailings/whatever worked and all 40 or so sockets work just fine.
I turn the switch on, the lights go on, I turn it off, the lights go off.
I run a star configuration for switches and light points, where all switches are on 12V DC and use a 'patchboard' to hook them to impulse relays which drive the lights. Still switch on/light on, but you can select which switch does what, easily hook up miltiple switches to multiple light points etc. Not domotica, but still much more dynamic than traditional build-once-change-never.
The electrician was installing the cat3 phone wires in the same holes as the A/C wires. It was guaranteed to induce a hum.
The correct approach is to keep the low voltage wires as far from the A/C as you can, and if they cross, keep the crossing at 90 degrees. Don't run them in parallel unless they are separated by feet (plural). If you have to, you can run them in grounded metal conduit as a shield.
I probably went overboard on this, but doing it inadequately meant 60 cycle humming on the phone lines and an utterly ghastly bill to rip the walls up and fix it.
He also was installing cat3 (POTS cable) and R59 cable (1970's cable TV stuff). I pulled that all out and threw it in the trash, putting in cat5 (cat5e and cat6 are better, but weren't available then) and quad-shielded RG6 cable.
Getting the best cable available cost maybe 20 or 30 dollars more, so it's crazy not to do it. The network and cable speeds have all increased dramatically since I installed it, and the cables have all worked like a champ.
Even the cat5 cables are happily carrying gigabit Ethernet.
I have a couple plugboards in the basement where all the wires terminate.
I did the whole thing for less than a grand. If an electrician had done it, it likely would have been 10 or 20x more.
If an electrician had done it, it likely would have been 10 or 20x more.
Hmm, that is like twice the amount one would typcially pay here. Still, don't froget the working hours you put in there :) plus the fact that usually technicians get their materials for cheaper than you do (also because in my case it's only 6% VAT instead of 21%). I did many such calculations when renovating and for some things it was actually cheaper to get a technician.
This usually works without any issues, but on one type of projector they had used a non-shielded network cable internally in the projector and if the projector lamp was lit juuuust at the right moment, the handshake would fail and the film would not play. Normally it wouldn't be a huge deal as the handshake happens just before the film and the lamp is usually lit on the beginning of the show long before the film starts. HOWEVER, there was this one cinema chain that had standardized their playlists in such a way that they for some stupid reason turned of the projector lamp in between the trailers and the film (I think to "introduce" the film) and then turned it on again just before the film with the result that the handshake failed 3 out of 10 times or so.
Long term solution was to replace the shoddy cable. Short term solution was to change all their playlist templates to blind the lamp instead of turning it off. Like they should have done to begin with.
Sure, they buy materials wholesale, but they bill you full retail for it. I installed around a mile of wiring :-)
But I also got it exactly the way I wanted, the wires run where I wanted, and I bought professional quality tools to do the work, and still have/use them. I like working with my hands now and then, it's viscerally satisfying in a way a keyboard never is.
The typical electrician gets it indeed for cheaper than market rate, then charges it to you retail rate plus 20% to account for the "trouble" of sourcing and purchasing it.
I never claimed that.
The typical electrician
Maybe you rather mean 'the typical electrician I met' or so because I know for a fact the rest of that sentence does not apply to the ones I met myself.
I know that twisted pair is supposed to be resistant to that, but I wasn't going to risk it and didn't have a good way to test it. I didn't want even a teensy bit of hum, and there isn't any :-)
Many houses have concrete walls, floors and ceilings, so you don't run extra tubes easily...
Reconfiguring switches is next to impossible and via existing switch wires you can dim/switch the lights but not change colour(temperature).
So here the original switches are removed and the connection is bridged (always on) and battery/kinectic powered ZigBee switches control the lights directly, even if the gateway is down.
Presumably that is not because of interference concerns but because of the danger of mixing high voltage and low voltage circuits in the same conduit, right?
As others have noted, conduit isn't usually used in houses in the west.
Source: US National Electrical Code
This means problems like fires spreading to adjacent buildings and fires trapping people where they can't escape are much reduced; you'd never see a repeat of the great fire of London in an American suburb because there's practically a fire break between every single home.
This is made affordable by America's vast tracts of land and high rates of car ownership.
https://en.wikipedia.org/wiki/Great_Chicago_Fire
The same day, a forest fire ravaged a number of small towns:
I had a house with mostly Armored Cable and came to appreciate it. Especially after I opened up a floor and found an exposed conductor on some Non-Metallic that had been chewed by a squirrel.
There are still existing functional knob and tube wiring systems that are 100 years old
I've gradually added GFCI outlets to each circuit. They're not grounded, unfortunately, but they do trip if something were to go wrong. And it allows us to plug in 3-prong plugs without using those horrible 2-to-3 adapters.
We had to change home insurance companies because Amica blacklisted us the instant they heard there was knob-and-tube wiring. A few other companies have the same approach. But it's not like homes are spontaneously combusting everywhere because of it.
Guess where I am ;-)
(Not in Chicago/Cook, though.)
Isn't twisting the pairs supposed to prevent that? Isn't that what makes it feasible to run telephone lines on the same poles as electricity, thus allowing the POTS system to be practical?
POTS is legacy now, so I'm not sure how much of a consideration it is for modern builds.
There are safety issues with running network and power cables close to each other, but generally on small domestic systems crosstalk between data and power shouldn't be a serious problem.
The exception is if you have a lot of hash on the power lines from USB chargers, unfiltered noisy motors, or white goods that generate both digital and analog noise.
Ferrites or other kinds of filtering can help. So can using shielded cat cable.
While the level of knowledge among electricians regarding network wiring is gradually increasing, the conventional wisdom for anyone who wants network wiring installed professionally is to hire a contractor that specializes in low voltage wiring.
Still I agree it isn’t worth the headache of issues to save $20 and it’s more futureproof to use better cables.
They also said that stp is a lot harder and expensive to install.
If it's truly done there's no reason for change. However getting there, to what for us is the most optimal configuration, is what was the main incentive for me. The way it is now it requires almost no ahead planning. I.e. for most rooms we had no idea on beforehand how we were going to pupulate them with furniture and which activity we'd do where, so I just went 'cable for lighting in the center, at the side on each wall, and some extra' and then put the switches in sensible places i.e. usually next to room entrance. Then during the next years hook up as needed and adapt if needed. E.g. couple of months ago we needed an extra desk for working form home and one extra for my GF's new hobby, so we just put some desks to a wall and instantly can get a light above it. With a fixed configuration you'd either need to think of that in advance, or use the light centrally in the room which makes you sit in your own shadow. or add lights you just plug in the wall socket but that's extra cable, and especially for desks it's hard to find a suitable one. Also throughout the years I've made small changes here and there to change things like being able to turn on the light in the bathroom from the bedroom, or turn on light in the kitchen from the place where we eat so you don't have to look for th kitchen switch in the dark. Sure those are just nice-to-haves but pretty convenient. I've been and lived in quite a lot of houses where the whole configuration was pretty akward. Though I get some people don't care about that.
I think by now I've got rid of all the R59 cable sockets and POTS stuff too except for one POTS socket in the cabinet that holds the fuse box. If anyone ever wants to reintroduce a wired telephone they can just reuse a CAT6 cable, but I doubt this will happen.
These days, of course, I don't use the POTS much.
You don’t need an elaborate, complex system to get a pretty big benefit from a little automation.
I just built a home, and bought and had the electrician install Lutron Caseta light switches for most of the switches (just the ones we might want to automate, not switches like closets or bathrooms).
Doing this has allowed us to even just turn off lights that were left on without having to get up, or turn on some exterior lighting at sunset/off at sunrise.
Pretty easy to set up, just works, and no overhead/undoing if you want to just use them as normal switches.
You hired a bad electrician. Any good electrician knows you can’t run power and data in the same conduit or pathway. NEC requires a divider in any junction box that contains low-voltage and line-voltage power, and also requires separate conduits/pathways for low-voltage and line-voltage power (can’t use the same stud hole to feed both through)
Spend more money on the electrician, and they’ll be better at their jobs.
Edit: I run electrical work
Similar to how close an electrical outlet can be to a sink, there are rules about how close a data cable can be to a current-carrying cable.
Sure, but aren't those rules for safety purposes and have nothing to do with crosstalk/interference?
The main value for smart home is in monitoring. I mostly use it for flood and door sensors without having to pay for a Ring/ADT subscription.
They are super useful for things like adding "sunrise" light in a bedroom with few windows/north facing, great for situations where you have a non ideal arrangement of light switches (one of my living room lights is on the switch circuit that my entry stairwell light is on). I also am very affected by light color temperature, so being able to easily transition lights from cool white to warm at night is very helpful for my sleep quality.
Rather than bring out the connections in each room, I use a toner to find the feeds and only bring out what I need when I need it.
https://en.wikipedia.org/wiki/Network_topology#Star
Each endpoint connects directly to the hub, rather than as a ring, daisy-chain, tree, or mesh.
I considered these systems when my house was built, and am very glad I didn't get them. I turn the switch on, the lights go on, I turn it off, the lights go off. I replace a bulb now and then.
That's it! I'm very happy with it.
But what I did do was run cat5 and RG6 to every room in a star configuration, which has paid off very very nicely. I did all that work myself because the electrician didn't understand words like "crosstalk" and I didn't want to find out after I moved in that the wires in finished walls didn't work.