On Mon, 21 Sep 2020 11:02:34 +0100, Newman
wrote:


On 20/09/2020 15:48, Newman wrote:

A hall with top and bottom lights and top and bottom single switches.

When top switch is on, only top light is on.

When bottom switch is on, both lights are on. Top light cannot be
switched off with top switch.

Any suggestions?

I am reluctant to investigate further as it is a rental property.

Regards


After much sketching, I think I have it figured.

Top switch is two way.

Switched live to bottom light also goes to NC of top switch. NO of top
switch is an always live wire. COM goes to top light.

That would explain why the top lamp has a brief flicker off when
switching the top switch with the bottom light on.

Any other theories?

Regards


I agree. Maybe only the top light existed originally, and both
switches are two-way so that either one can control the light. The
hall light was added later, connected to one of the two wires joining
the two-way switches.
--
Dave W