mains inline powertap with no neutral.

[pachuma]

And here a few renders of the board: top layer load switching + micro-controller and sensor interface. botton layer - PSU + decoupling + filtering.

[ptricks]

What I found weird was in NZ the neutral and earth are tied together in the fuse box.! Is that normal? I''ve seen this in a few houses in NZ so not dodgy wiring in my hours.

In the past items used the neutral as the chassis ground.  In the USA it wasn't until a few years ago that appliances like a clothes dryer used a separate ground.Homes in the USA are connected to a transformer that steps down the 4-8KV from the utility to 240VAC with a center tap that becomes the neutral . Appliances were shipped from the factory wired for Hot-Neutral-Hot wiring, 240VAC between the two hot and 120VAC from either hot to neutral. There was a tab that connected the metal frame to the neutral wire.  The idea was that if one of the Hot circuits contacted the metal it would short and trip the breaker.  It was done that way for over 75 years before changing to the new system required 4 wires, the same 3 as before plus a dedicated ground .   

The idea behind having a dedicated ground wire is that nothing on the circuit normally uses that wire for a return path so if a device fails the wire is more than capable of carrying the current back to the panel and also in conditions where the neutral comes loose from the socket you would normally have the Hot now flowing through the chassis. A separate ground fixes those issues.
 

[pachuma]

And to finalize the image, here is the light switch on my daughter's bedroom which I engraved by hand for her.

[Uncle Vernon]

What I found weird was in NZ the neutral and earth are tied together in the fuse box.! Is that normal? I''ve seen this in a few houses in NZ so not dodgy wiring in my hours.

Yes, it's called TN-C-S. One combined conductor in the supply, separate earth and neutral in the installation.

Although sane countries leave doing this to the supplier.

In ANZ it's known as MEN,  Earth conductor should never carry anything other than fault current, they are not a handy return path. The regs are quite specific to how and where a neutral link is grounded.  Nothing sane about leaving this to the supply authority, the M in  MEN stands for multiple, and caters better for service with multiple structures than any supplier based scheme.

Still if your populace resides in limpet like council flats, clung together on a cold damp rock in the north sea, you'd likely see less advantages from an MEN scheme.

[Monkeh]

What I found weird was in NZ the neutral and earth are tied together in the fuse box.! Is that normal? I''ve seen this in a few houses in NZ so not dodgy wiring in my hours.

Yes, it's called TN-C-S. One combined conductor in the supply, separate earth and neutral in the installation.

Although sane countries leave doing this to the supplier.

In ANZ it's known as MEN

No, the system is quite clearly known as TN-C-S. MEN means Multiple Earthed Neutral. The equivalent term over here is PME: Protective Multiple Earthing. This merely refers to method of connecting the PEN to earth in multiple locations due to the risks of a lost neutral, there are many TN-C-S installations which are not PME/MEN, although you won't find them being freshly installed, not for domestic customers, anyway. The facts are the same: One conductor in the supply cable, separated into neutral and a protective earth within the installation.

Nothing sane about leaving this to the supply authority, the M in  MEN stands for multiple, and caters better for service with multiple structures than any supplier based scheme.

Plenty sane about it. It's their network, it's their neutral and earth to maintain, how can they reasonably place their trust in homeowners to ensure it's good? You put an earth stake in the trench with every joint on the cable, and hey presto, PME/MEN.

Now, there's equipotential bonding, which is another matter, and never to be used as an earth.

Still if your populace resides in limpet like council flats, clung together on a cold damp rock in the north sea, you'd likely see less advantages from an MEN scheme.

There's no need to be insulting, especially when you're wrong.

[Uncle Vernon]

Plenty sane about it. It's their network, it's their neutral and earth to maintain,

Their earth? What frigging earth? Their is no distributed earth to maintain.

how can they reasonably place their trust in homeowners to ensure it's good?

What the hell has it got to do with home owners? Earth stakes and neutral links are the responsibility of installing contractors.

You put an earth stake in the trench with every joint on the cable, and hey presto, PME/MEN.

No you don't! You can have 50 joints in an earth conductor without any of them requiring a ground stake. You link the neutral at the point of supply  (no, not the point of attachment) of each premises. Multiple earth stakes are permissible (desirable) but all need to bond to the main earth link.

There's no need to be insulting, especially when you're wrong.

I wouldn't know, I am seldom wrong!
A note to the UK, having plugs the size of dinner plates does not mandate your system to be better or safer than other countries schemes.

[Monkeh]

Plenty sane about it. It's their network, it's their neutral and earth to maintain,

Their earth? What frigging earth? Their is no distributed earth to maintain.

The PEN!

Or are you suggesting that the nice low earth impedances seen in your MEN systems are nothing to do with that big conductor linking all the earth stakes (wherever they may be fitted) together?

You put an earth stake in the trench with every joint on the cable, and hey presto, PME/MEN.

No you don't! You can have 50 joints in an earth conductor without any of them requiring a ground stake. You link the neutral at the point of supply  (no, not the point of attachment) of each premises. Multiple earth stakes are permissible (desirable) but all need to bond to the main earth link.

Which is exactly the same as putting an earth stake in the trench at supply cable joints. You're just moving it out of the supply and into the installation.

A note to the UK, having plugs the size of dinner plates does not mandate your system to be better or safer than other countries schemes.

And neither do your damn-near identical plugs except for the lack of fuses!

You want to try having a technical discussion without assuming I know nothing because I'm from the UK, or are you just going to insist your system (which is the same, you just leave the earthing arrangements to the installation instead of the supply, in which case you may as well use TT) is better because you use different letters?

[ivan747]

OK, so here is an image of one of the light switches I've got installed around the house that uses the capacitive PSU and load switching.

Looks beautiful! Where can I get more info on these? They use a microcontroller, so the OP  may want to take a look.

[johnnyfp]

I like the glass. Is it normal or toughened? Because I asked around and nowhere would do small light switch sized toughened pieces for reasonable prices.
My idea for that project, which wouldn't' use this one live setup was to control  two  cap sensitive strips with led feedback through the glass.

Then it would dim some led lights in the room.

But I may actually resort to using a android unit instead as they are as cheap as chips these days. Specially a cap based one with WiFi.

[pachuma]

The glass is plain glass, you can use any type of glass you want.

This is a project I got on commission to do a reference design. I will publish the "micro-catalog" that I delivered to the customer so that you can see they entire idea behind it. The switch also has a see through the glass LED that indicated the switch status and you could change its color depending on the glass too.

Thank for the comments, they are very much appreciated.

[Uncle Vernon]

are you suggesting that the nice low earth impedances seen in your MEN systems are nothing to do with that big conductor linking all the earth stakes (wherever they may be fitted) together?

I'm questioning that definition of all.

Which is exactly the same as putting an earth stake in the trench at supply cable joints. You're just moving it out of the supply and into the installation.

But not the same as at every joint, which is what you had previously suggested.

neither do your damn-near identical plugs except for the lack of fuses!

Identical? Fitting fuses to AU plugs would be of little use particularly given the difference in the way we reticulate cable to GPOs.

are you just going to insist your system (which is the same,

While our standards may have distant origins from some British standards, the current ANZ practices are worlds apart from those.

[Monkeh]

Which is exactly the same as putting an earth stake in the trench at supply cable joints. You're just moving it out of the supply and into the installation.

But not the same as at every joint, which is what you had previously suggested.

Now you're picking holes because you have nothing else to do.

neither do your damn-near identical plugs except for the lack of fuses!

Identical? Fitting fuses to AU plugs would be of little use particularly given the difference in the way we reticulate cable to GPOs.

See above.

are you just going to insist your system (which is the same,

While our standards may have distant origins from some British standards, the current ANZ practices are worlds apart from those.

That doesn't change the fact that the earthing system is the same. In fact, you probably do earth the neutral on the supply cable directly, rather than at the installation, you just insist on making the connection between PEN and PE in the installation, rather than the supply head.

[Uncle Vernon]

Now you're picking holes because you

I'd consider it more pulling chains!

That doesn't change the fact that the earthing system is the same.

So you're saying yours is better but still the same. OK. you run with that.

[Monkeh]

Now you're picking holes because you

I'd consider it more pulling chains!

*yawn*

That doesn't change the fact that the earthing system is the same.

So you're saying yours is better but still the same. OK. you run with that.

And here I was thinking this forum was for discussion, not pointless trolling.

[HackedFridgeMagnet]

That doesn't change the fact that the earthing system is the same. In fact, you probably do earth the neutral on the supply cable directly, rather than at the installation, you just insist on making the connection between PEN and PE in the installation, rather than the supply head.

In Tassie, Australia the whole pen of the conductor is within the installations main switchboard. I did one the other day, its about 50mm long. Here supply authority normally does not do it.
There might be other allowable way you can do it when attaching to different suppliers.

MEN is really just a flavour of TC-N-S, is says as much in AS3000.
 
Now I have said my bit I can safely say:
Ok lets not hijack the original posters thread.

Ps Nice light switch, can you make them smaller?

[Uncle Vernon]

Ok lets not hijack the original posters thread.

Ps Nice light switch, can you make them smaller?

About 10 years back the major suppliers released several competing ranges of inline control devices, motion sensors, time-clocks etc They worked effectively with incandescent loads but were next to useless with everything else resulting in most lines being withdrawn from sale. With the humble light bulb now almost a museum piece I cannot see the situation being any better for such devices.

Those switches do look good but it appears they suffer the same shortfall with most commonly used loads.

[pachuma]

Ps Nice light switch, can you make them smaller?

The current PCB is about 45mm x 45mm it is perfect to retrofit in the light switch socket. You can integrate a bit more the UC componentes, but the components that are imposing the size is the main X2 capacitor, large'ish bypass caps, filter (the coil has to withstand 3A) and track clearance. I guess you could still shrink the design another 10mm x 10mm.

As far as the glass sheet is concerned, you can have it in any size. Perhaps the smalles size is that of the sensor PCB or the size of the wall switch potting box.

Looks beautiful! Where can I get more info on these? They use a microcontroller, so the OP  may want to take a look.

Thanks for the comment, here is the flyer/catalog I pitched for the customer a while ago to present to him his reference design.

Those switches do look good but it appears they suffer the same shortfall with most commonly used loads.

Yes, I think that was what I commented in the first post. Driving incandescent loads is great and it works spotlessly. However, inductive loads, switched loads they don't behave as they should nor is it recommended. I tried it out with a good range of CFL bulbs with various degrees of success. For example, those sold by Ikea work well on all their CFL range. Dimmable CFLs work just as good as incandescent bulbs. For fluorescent lights is a big no, no (given how the load is driven).

For inductive load configurations you would need a separate phase feeding the switch's electronics which was the other configuration I developed for the customer (didn't say much about it because of the subject of the thread).

The last thing was that you can calibrate it to be touch or proximity sensitive (the latter is great fun seeing people do their Jedi swipe to switch on the light )

Anyway, here is the "catalog" that went on as part of the final delivery hope you like it.

One thing I do love about the switches I have around the house is that I no longer need to clean finger marks around light switches  , and they do look very cool.

[somlioy]

How do you mount the glass sheet to the wallbox?

[pachuma]

How do you mount the glass sheet to the wallbox?

That's a quiz question

[SeanB]

You take a blank wall plate and use clear epoxy to attach the glass to it?

[pachuma]

You take a blank wall plate and use clear epoxy to attach the glass to it?

Good answer but no. If you look at the pictures the glass surface is flat with the wall. The solution doesn't use any epoxy at all. The glass can be removed without effort but it doesn't move once fitted.

Also remember that the capacitive sensor probe has to be touching the glass too.

[SeanB]

You made a recess in the wall to accommodate the plate then simply held it in place with either velcro or a magnetic hold down on a metal plate behind the glass.

[pachuma]

Very, Very close. The sensor probe is fitted by screwing it to the wall potting box. The glass is fitted to the sensor PCB with neodymium magnets.

[ivan747]

And you have a patent on that. It's a great idea, I'm glad you applied for a patent.

[pachuma]

Pending.