Two 2 way and intermediate switch

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Morris91

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Hi I'm new to this site im a first year apprentice, just wondering the intermediate switch I had to wire in college for a lighting circuit had L1 L2 L3 L4 isit still really both L1 at the top and both L2 at the bottom. 

Also the way in the wiring diagram I seen online it shows both black connect to L1 and both Greys connecting to L2 from the two 2 ways switches but my tutor said to wire them up crossed so grey at top in L1 black second L1 and then  black bottom left L2 and grey bottom right L2 the diagram attached is the one from online any help if this is right ? 
slide_12.jpg.c5cfddd3728fd24a24e2aa456aef6fa4.jpg


 
There is no right or wring way. the important thing is whichever colour you use as the common in the 2 way switches, is the one that just passes through the intermediate switch.

I am not sure that diagram will work with all intermediate switches. Normally it's one pair into the TOP of the switch and one pair out of the bottom of the switch, but some makes of switch might be like the one shown, but I have never seen one like that yet. The important thing is take not of how the terminals are labelled, not their position on the switch.
 

 
my tutor said to wire them up crossed


I was taught this when I was an apprentice for some reason, no-one ever could tell me why. I have never actually done it that way though, just stick them in anywhere.

 
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When wiring 3 way (or more) lighting, I like to make it so when all switches are "up" the light is off. sometimes when comissioning, that means swapping one of the strapper pairs over to achieve that.
 

 
I've wondered if it was because of that, strange that it has become detached from the intermediate switching though. I mean, what good is randomly swapping the in/out pairs on an intermediate if you have no idea where the strappers are at the other ends?

I did used to do some work for a firm that wanted all lights to be off when switches are in the up position. This sort of thing defeats the object of using twin red, or singles though.

 
Morris 91   As Dave said ,  think how the switches work ....C   means common as in ...it is common to the other two terminals ..so its either switched to L1 or L2  .

Have a look at the way an intermediate switch works  ...It either switches straight through  ..or.. it crosses them over .

The two way you show in your post is called  ( round here )  a conversion  two way by the way . 

 
all great answers which will help I know I'm only just starting off and will pick it up along the way on site, but college is just 1 hour practicle a week not easy to practice one circuit in. But like I said was just wondering why my tutor said to cross the wires at the intermediate instead of two at the L1 and two at L2. Thanks for the help all 

 
all great answers which will help I know I'm only just starting off and will pick it up along the way on site, but college is just 1 hour practicle a week not easy to practice one circuit in. But like I said was just wondering why my tutor said to cross the wires at the intermediate instead of two at the L1 and two at L2. Thanks for the help all
If you put one pair into the two L1's and the other pair into the two L2's, then in one position of the switch the light will never turn on. Each pair has to go into an L1 and L2

Noting stopping you buying some switches and making up your own test board to try it all out at home and work it out.
 

 

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