dumb and dimmer

[oneohm]

my household dimmer controls 3 outlet sockets in the walls which may or may not have standard lamps plugged in. As I connect each lamp I would expect the current to be shared between them and hence the light output of each to reduce as the next is added The light output remains unchanged throughout however How is this possible if the dimmer is in series with all three

[IanB]

my household dimmer controls 3 outlet sockets in the walls which may or may not have standard lamps plugged in. As I connect each lamp I would expect the current to be shared between them and hence the light output of each to reduce as the next is added The light output remains unchanged throughout however How is this possible if the dimmer is in series with all three

Question: "How is this possible if the dimmer is in series with all three?"
Answer: The dimmer is not in series with all three.

The dimmer is in parallel with all three sockets, so that each socket is independent of the other sockets, and each socket individually receives the dimmer output.

[jeroen79]

The dimmer is in series with the lamps.

But the lamps are parallel to eachother.
So each will draw it's rated current when the dimmer is conducting.

[ebastler]

The dimmer is in series with the lamps.

But the lamps are parallel to eachother.
So each will draw it's rated current when the dimmer is conducting.

Right. And one more thing which the OP may not be aware of: The dimmer is not a variable resistor. (If it were, the OP's concern would be correct.) Rather, it rapidly switches between conducting and not conducting the mains voltage, with each period of the 50Hz or 60Hz mains AC. Therefore, the lamps always "see" a voltage source, and, as stated, will draw their rated current independent of how many lamps are connected in parallel.

[oneohm]

thankyou You are a gentleman

[neko efecktz]

WARNING WILL ROBINSON...
You said you have the dimmer controlling wall outlets.

This can be very dangerous to anything other than incandesant lamps plugged into these outlets.
God only knows what would happen to a switch mode power supply if it was plugged in.
Most mains powered house hold items other than refrigerators, microwave ovens dish washers washing machines use switch mode power supplies.

Most domestic dimmers are also ONLY CAPABLE of handling up to about 500 watts.
They DO NOT operate compact fluorescent bulbs and even LED globes are not the best with a dimmer.

ALSO driving a transformer supplied device i.e. stereo amp through a dimmer NOT ON.     edited......
Check out BIG CLIVE    https://youtu.be/fWh2obSY0dQ
                                     https://youtu.be/_4PwYm_7HKg      around the 14 minute mark  re inductive loads       edited......


Please reconsider your way of dimming lamps.
DIMMING WALL OUTLETS IS A NO NO...

BILL.

[stevelup]

It's quite normal here in the UK to have wall sockets on lighting / dimmer circuits, but we use small round pin 5A sockets to differentiate and ensure inappropriate things are not plugged in.

[tggzzz]

It's quite normal here in the UK to have wall sockets on lighting / dimmer circuits, but we use small round pin 5A sockets to differentiate and ensure inappropriate things are not plugged in.

Really? I've never seen nor heard of that.

Where have you seen that?
Has the installation been certified as conforming to the IET Wiring Regulations?

[Simon]

It's quite normal here in the UK to have wall sockets on lighting / dimmer circuits, but we use small round pin 5A sockets to differentiate and ensure inappropriate things are not plugged in.

I think you are referring to many decades ago.

[daveshah]

I've seen sockets like that connected to dimmers (or, not so relevant here, light switches) even in fairly recent installs although I know at least one of those was dodgy (metal switches and dimmers not earthed...). It's certainly a de facto standard if not an official one.

[Simon]

Last time I saw any mention of these was in a Reader's Digest do it yourself manual from the 19 fifties. No doubt there are plenty of old school people around that would still use these if they could. Personally I don't think I have ever seen 1 or used 1. Perhaps seen on a very old piece of equipment that certainly never seen one in use. I doubt very much that they are currently allowed by official standards.

[Gyro]

Yes, I've seen them (5A round pin) used in hotels too. Not necessarily dimmed, but certainly on a separate light switch. The also prevent customers from plugging anything else in. Presumably they would be even more likely to have to follow current wiring regs.

[Simon]

So presumably these are the lights only? I've never seen a light sold one on.

[Gyro]

Yes lights only. No, neither have I. Presumably they would be fitted on installation.

P.S. I just checked Farnell, they have 5A round pin sockets listed, but no longer stocked (must have been recent though. Presumably they had no demand for them, it would be more likely an electrical distributor product.

P.P.S. Yes, current stock at Screwfix... http://www.screwfix.com/p/schneider-electric-lisse-5a-1-gang-round-pin-plug-socket-white/8806j

[Simon]

Well I assume a different plug is to stop you plugging another device into a dimmed socket but then I liked that you could otherwise use on full power on any socket can't be plugged in. It means that if you have a portable light you also need another socket. It's a bit of a retarded concept in today's day and age particularly as dimmers are for incandescent light bulbs anyway and would work atrociously with LED lights in most cases. If you have a fixed wired dimmer for an LED light I can understand that but portable things like desk lamps should incorporate their own dimmer if one is required.

[stevelup]

This is absolutely normal on higher end properties. Imagine you've got a very large room with numerous floor standing lights all controlled via a home automation system.

Or more simply, you may just want to be able to turn out all the lights in the room from a single switch.

Or perhaps bedside lights - so you can turn them on and off from a switch near the entrance to the room.

And definitely as mentioned already above, in hotel rooms.

Of course it's compliant with the wiring regs - why wouldn't it be?

Check out this link.

This one supplier stocks around 40 different types in many contemporary designs and colours. It's hardly a dead idea or one from many decades ago. The plugs have sleeved pins and meet current standards as well.

[Simon]

We obviously I don't travel in such exulted circles

[Gyro]

Of course it's compliant with the wiring regs - why wouldn't it be?

Check out this link.

This one supplier stocks around 40 different types in many contemporary designs and colours. It's hardly a dead idea or one from many decades ago. The plugs have sleeved pins and meet current standards as well.

I like the way 16A 415V sockets show up in that search, presumably for very large and very high end properties. 

[stevelup]

I tried to narrow the search results down, but lost too many useful results!

[neko efecktz]

in the fifties wouldn't a wall dimmer have been a rheostat?

BILL.

[Simon]

No but they had 2 different sizes of plugs for different loads. I don't think it was even about lights.

Sent from my Moto G (4) using Tapatalk

[Gyro]

Ooh, I see modern 5A plugs even have sleeved pins now, in line with normal 13A ones... 

https://www.tlc-direct.co.uk/Products/TLPT5.html

[Zero999]

Of course it's compliant with the wiring regs - why wouldn't it be?

Check out this link.

This one supplier stocks around 40 different types in many contemporary designs and colours. It's hardly a dead idea or one from many decades ago. The plugs have sleeved pins and meet current standards as well.

I like the way 16A 415V sockets show up in that search, presumably for very large and very high end properties. 

I've never seen a 16A 3 phase connector in a domestic setting. They are designed for use in industrial applications. Single phase 230V (blue), 110V (yellow) and 24V (violet) are also available. If a house has them, it would be because someone's installed them in their workshop or garage.

[Gyro]

(obviously weak) joke!   

[tggzzz]

Of course it's compliant with the wiring regs - why wouldn't it be?

There are many many installations that are non-compliant; people do strange and dangerous things. Some of them are posted elsewhere on this forum.

Check out this link.
This one supplier stocks around 40 different types in many contemporary designs and colours. It's hardly a dead idea or one from many decades ago. The plugs have sleeved pins and meet current standards as well.

Shrug.

There are many things than can be legally sold in the UK, but which are illegal to use (or can be illegally used).