Top and Bottom Stairs 2-Way Switches not working correctly

[John D v2.0]

OK got it at last!, the point is you can't use *only* t&e between the two switches, and feed the live in separately. It's not the t&e that's the problem, it's the fact that the live feed doesn't run down the same chases as the Strappers.
So t&e isn't the problem, it's the way it's used. Which reassures me I won't have to chop out my wall where I used 3no t&e for 2no 2 way switches and one standard switch!

 

[bernardgreen]

Two lives in opposite directions has the same effect - is the same - as live and neutral.

In terms of electro magnetic interference yes, that is true the two currents flowing in opposite directions oppose and cancel each other's magnetic field.

In terms of electro static interference when the switch is OFF the Live voltage and the Neutral voltage ( via the lamp ) oppose and cancel each other's electro static field.
When the switch is ON the Live voltage and the Switched Live voltage are the same and enhance each other's electro static field.

 

[EFLImpudence]

OK got it at last!, the point is you can't use *only* t&e between the two switches, and feed the live in separately. It's not the t&e that's the problem, it's the fact that the live feed doesn't run down the same chases as the Strappers.
So t&e isn't the problem, it's the way it's used. Which reassures me I won't have to chop out my wall where I used 3no t&e for 2no 2 way switches and one standard switch!

Well yes, the only thing wrong with T&E is that it's deficient in the conductor department.

Of course, in the tradition of electrical abbreviations, T&E does stand for Three and Earth.
.

 

[John D v2.0]

Haha twin, triple, three, ten..!
Everything's ambiguous
Cheers,