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I Ripped Out a £6k Lighting System

robdobson.com

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Re: I Ripped Out a £6k Lighting System

#261

Post by crooked-v »

hamandcheese wrote: post #226

The ONLY wireless lighting system I will ever use is Lutron Caseta light switches. They are magic and don’t require a neutral cable, unlike just about every other smart dimmer, which means they can be swapped in place of literally any light switch in any home. If the Lutron hub is unplugged, the switches continue to operate as normal light switches. They also operate as normal light switches at all other times. So no…

What I'd really like to find is some variety of smart switch with a mode change between 'control the wall circuit' and 'leave the wall circuit always on and send commands over the network', so that the same switch hardware can be used everywhere but you can change the mode for specific circuits that have smart bulbs.

I have no idea how one would design this in an intuitive way, though.

Re: I Ripped Out a £6k Lighting System

#262

Post by minitoar »

dylan604 wrote: post #245
core-questions wrote: post #239

Earlier quoted context omitted.

I was confused as all get-out about what a "wire nut" is, turns out Marettes are not what everyone calls 'em!

without looking it up, sounds like you are referring the brand name or the manufacture/distributor of wire nuts available at your local hardware store.

It's actually based on the name of the inventor, a Canadian, and is commonly used in Canada as a generic name.

Re: I Ripped Out a £6k Lighting System

#263

Post by toast0 »

MaxBarraclough wrote: post #250
walshemj wrote: post #233

Earlier quoted context omitted.

They did use the correct wiring standard T-568B ? and the runs where < 90m

> and the runs where 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?

> 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.

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.

Re: I Ripped Out a £6k Lighting System

#265

Post by w4tson »

t0mas88 wrote: post #118
WalterBright wrote: post #56

I wouldn't buy a house with such a system in it, and I doubt anybody else will, either. Who wants to become an expert on these systems just to turn the lights on? Not a chance. 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…

The easy solution is to have the intelligence in the lightbulbs the way Philips, Osram and IKEA did on their Zigbee based systems. 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…

Out of interest, what light switches did you choose?

Re: I Ripped Out a £6k Lighting System

#266

Post by WalterBright »

stinos wrote: post #113
WalterBright wrote: post #91

Earlier quoted context omitted.

Crosstalk is when two wires are close together, one induces a voltage in the other (it's how transformers work). The trouble with house wiring is if you run a phone line parallel and close to an A/C line, it will induce a 60 cycle hum in the phone line, which will drive you utterly mad. 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 corre…

Sorry should have been more clear; I'm an eletronics engineer so I know what crosstalk is, it's just that I didn't understand how this would be an actual problem with CAT5. Phone line, that's something else though. 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…

> technicians get their materials for cheaper than you do

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.

Re: I Ripped Out a £6k Lighting System

#267

Post by WalterBright »

stinos wrote: post #113
WalterBright wrote: post #91

Earlier quoted context omitted.

Crosstalk is when two wires are close together, one induces a voltage in the other (it's how transformers work). The trouble with house wiring is if you run a phone line parallel and close to an A/C line, it will induce a 60 cycle hum in the phone line, which will drive you utterly mad. 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 corre…

Sorry should have been more clear; I'm an eletronics engineer so I know what crosstalk is, it's just that I didn't understand how this would be an actual problem with CAT5. Phone line, that's something else though. 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…

> I didn't understand how this would be an actual problem with CAT5

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 :-)

Re: I Ripped Out a £6k Lighting System

#268

Post by WalterBright »

bleepblorp wrote: post #200
WalterBright wrote: post #91

Earlier quoted context omitted.

Crosstalk is when two wires are close together, one induces a voltage in the other (it's how transformers work). The trouble with house wiring is if you run a phone line parallel and close to an A/C line, it will induce a 60 cycle hum in the phone line, which will drive you utterly mad. 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 corre…

I would seriously question the overall competence of any electrician who ran any low voltage cable in direct contact with AC power cables. This practice is not permitted by the electrical code. An electrician who does not respect that code requirement might be cutting corners with the code in other areas, too. While the level of knowledge among electricians regarding network wiring is gradually increasing, the conven…

This was 20 years ago and the general contractor thought I was nuts to pre-install all this cabling. This all changed a year later, and network cables pre-installed became normal.

Re: I Ripped Out a £6k Lighting System

#269

Post by casenjo »

nucleardog wrote: post #87
Maha-pudma wrote: post #61

I don't get it. What's the point in these systems? Genuinely. Why would I ever need this? Just like a "smart" doorbell, fridge, meter. I would love for someone to be able to explain the benefits to me over the normal, cheap, completely working "dump" version. The only "smart" device I own is a TV and it is crap, worse thing I've ever bought.

For me it started with a single wifi lightbulb. My wife often gets into bed with the baby. If the baby falls asleep before the light is off, she doesn't want to get up to have to turn the light off since it will wake the baby. Now she can just turn it off from her phone. Kinda just expanded from there. Now a good chunk of the regularly used bulbs in the house are "smart". Basically what it means is that if you turn a…

> The lights in my office come on when I walk in if it's dark, and when I unlock my computer it shoots a message out over a MQTT broker which my automation takes as "someone is occupying this space now" and leaves them on. When I lock my computer, two minutes later if no motion is sensed it'll turn them off.

What did you do to send the message when the computer locks/unlocks? This is an exact use case I could make use of

Re: I Ripped Out a £6k Lighting System

#270

Post by WalterBright »

quickthrowman wrote: post #193
WalterBright wrote: post #56

I wouldn't buy a house with such a system in it, and I doubt anybody else will, either. Who wants to become an expert on these systems just to turn the lights on? Not a chance. 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…

> 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. 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 separ…

The low voltage in the house is completely separated. The wall outlets are widely spaced. It even comes into the house in a different location and a different trench.
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