INTERMEDIATE SWITCH PROBLEM!!!

[99thomasar]

Hi all!

I have been replacing all of the plain white switches and sockets in my home with nicer, brushed steel ones and I have managed to do this correctly with every other type of fitting except for the last two pesky intermediate switches!

I photographed the set-up of the old switch and labelled every wire before removing it, then tried to replicate this on the new switch. The trouble is that the new switch is laid out differently to the old one. It's definitely an intermediate switch, but there are two L1's at the top and two L2's at the bottom, whilst the old switch has L1 / L2 at the top and L1 / L2 at the bottom.

The ordinary 2-way switches in the circuits have been replaced and are working normally with the old intermediate switches, yet when I fit the new intermediates the switches do funny things, like not working at all or only working partially, or only working in specific set-ups of on /off positions.

For the record, have tried swapping the wires around to different positions with no luck, I have earthed the metallic switches and I have tried both of the new intermediate switches in both of the circuits. I have now reinstated the old switches and the circuits are working properly again.

It can't be a fault with both new switches, can it? Surely I just need to get the correct layout on the wiring, but how?

If somebody could explain how to wire this correctly using the image below I would be eternally grateful!

Untitled

• 99thomasar
• 28 Sep 2013
• 1

 

[Spark123]

Have you tried 1 to L1a, 2 to L1b, 3 to L2a, 4 to L2b?

 

[ban-all-sheds]

Have you tried using a multimeter to identify which terminals are which?

 

[333rocky333]

as ban says best to use a meter to test switch rather than quessing

position 1 terminals switch =
position 2 terminals switch x

once terminals found switching = put one brown and corresponding grey one side, and the other two on the opposite side

The brown and grey cables each side have to be part of the same cable

 

[securespark]

You've tried browns in a's and grey's in b's?

 

[riveralt]

Have you read the instructions that came with the new switch?

 

[sparkwright]

In this case, I wouldn't take any notice of the terminal markings. Just copy the actual positions of the wires

for example

if a wire is in top left of old switch, put it in top left of new switch.

Not scientific or logical I know, but have noticed some intermediate switches have illogical markings on them - but simply copying the physical positions of the wires does seem to work.

I should stress this method does NOT necessarily work on other accessories, and it's always very important to check and double check.

 

[JohnW2]

Am I not right in saying that, functionally speaking, there are only two rational possibities:

• 1...browns on one side (left or right), greys on other side - i.e. per old switch
  OR
  2...browns at top, greys at bottom (either way around)

If that's the case, then one of those two configurations has surely got to work? There is a third, rather bizarre, possibility (brown diagonally opposite brown, and grey diagonally opposite grey) - so I suppose one could try that 'in desparation' if neither (1) nor (2) worked. The saving grace of all this is that (unlike many wiring situation) one cannot do any harm at an intermediate switch, no matter 'which one connects to where' - so, unusually, 'trial and error' is not dangerous - it either works or it doesn't (even though identifying the switch terminals with a meter is the correct and sure way to solve the problem).

Kind Regards, John

 

[ericmark]

Although you say it's an intermittent switch is it written on it or have you tested it?

I have in the past been supplied with double pole switched instead of intermediate switches and my guess is this is what has happened to you?

 

[JohnW2]

Although you say it's an intermittent switch is it written on it or have you tested it? I have in the past been supplied with double pole switched instead of intermediate switches and my guess is this is what has happened to you?

Various people have suggested that he should test it, but that doesn't seem to have happened, at least not yet. Although I doubt that it would have 'intermediate' written on it, it would surely be very odd, and unusual (unkown?) for the treminals of a double-pole switch to be labelled L1/L1/L2/L2, wouldn't it?

Kind Regards, John

 

[99thomasar]

Thanks for all the help people. Spark123 had it right - even though it seems counter-intuitive. Legend!

 

[EFLImpudence]

 

[333rocky333]

what make was this switch