Not Seen Before

[androiduk2002]

I have looked closely (with out undoing cables) and I am sure its 1 3&E cable not a 2&E with a second single run in.

 

[Lurch]

Looks like it, but if it was a 6241Y it would be red anyway, so you'd have 2 reds and a black.

 

[androiduk2002]

One question that someone could answer , on a normal 2 gang the commons are both at the top of the switch on the one in the picture the the right hand one is common at top but the left hand on is common at bottom , is this how it was made or did the sparks swap it at the time of installing ??

 

[Lurch]

Some switches have all gangs aligned the same way up, others have them alternately up and down. I would say it's more common to have them the way the switch in your pic is. Some are changeable on site, some just throw springs and contacts everywhere when you take the screws off. The former are handy for making 2 gang intermediates.

 

[gselectrical]

Some switches have all gangs aligned the same way up, others have them alternately up and down. I would say it's more common to have them the way the switch in your pic is. Some are changeable on site, some just throw springs and contacts everywhere when you take the screws off. The former are handy for making 2 gang intermediates.

Had a phone call yesterday from "a friend". He was asking why non of his lights where working after replacing all the switches. "Well are the switches connected up correctly?"......."Well I just did it like the old ones was"....Which of corse where a different make.

He'd also replaced the DP water heater switch, the neon was permanantly on (which he blamed on the manufacturers) nothing to do with the fact he'd connected it up the wrong way around. headbang

 

[PBC_1966]

Was told last week at college the final rose will be the one with 2 T&Es in

Its been worth while looking into it and discussing on here as its not something covered (yet) in college we have just been taught the modern method

This is something I've found rather worrying for some time. It seems that we have courses being taught which just assume that circuits are wired a specific way, and barely mention the fact that other arrangements are common and quite acceptable. I've seen the same sort of assumptions in some DIY books.

Two T&E's at the rose could mean the last light on the circuit if one of those cables is the switch loop. Or it could be one of several "last" lights on the circuit if the feed is split at some earlier point. Or it could mean that the feed into that light is already switched and the second cable runs to another light which is controlled by the same switch (identified by the simple parallel connection in that case).

How strange.This ties in nicely with the other thread about 3 core and it not coming in sensible colours!

Doesn't it just?! After a long time of wondering why 6243Y was red/yellow/blue rather than red/yellow/black, here is proof that the latter exists. I've certainly never seen it before. Cheap because of the "mistake" in production? A specially made batch?

On the general topic though, the arrangement is one I've certainly used in the past (minus the confusing mix of new brown sleeving on old colors!). There are many different variations with 2+E and 3+E to give the required switching of lights while minimizing the length of cable runs.

For example, physical sequence of devices in order of distance from power source:

Power -> Switch 1 -> Light 1 -> Light 2 -> Switch 2.

With loop-in at the lights you might take power to light 1 and onto light 2 with separate drops to each switch. But if switch 1 and light 1 are some distance apart and the power is going right past the location of switch 1 to get to light 1, it saves extra cabling to just drop the power into switch 1 then use 3+E between switch 1 and light 1 to provide permanent feed to continue to light 2 plus switched feed for light 1.

 

[androiduk2002]

Its good when you have the ability/common sense to look at what you can safely, its part of the learning process, alot have said its how they wire switchs/have wired, so its something that I am sure I will come across at some point, In defence of the colleges and courses at the moment we are learning the formules in theory (most important) and in practical we have a work book to follow , i am guessing that is made up with with the regs in mind and of course they will teach the recommened methods, if everyone followed the recommened methods life would be a bit boring IMO.

IMO what makes a good spark is his ability to not only do things safely and follow the regs but to not be phased (excuse the pun) by coming across something he hasnt seen before , but to be able to take it in his stride look at the layout trace the wires and find out what has been done and either fix it or confirm that even tho its not regulation that it is safe.

The method I found, is interesting as yes is does save cable all be it only a little bit, but it highlights that things are done differant by differant sparks. What did surprise me was the use of a through crimp inside a batten fitting there is little spare space as it is.

 

[Lurch]

There are many different variations with 2+E and 3+E to give the required switching of lights while minimizing the length of cable runs. For example, physical sequence of devices in order of distance from power source:

Power -> Switch 1 -> Light 1 -> Light 2 -> Switch 2.

Also used this one quite a bit, particularly useful for rewires, saves finding a route up for a feed somewhere, just bring it up the landing switch with the 2 way drop. Less chasing.