On Mon, 30 Mar 2020 23:38:19 +0100, Robin wrote:



Belatedly realised this is probably covered in the Wiki, and lo,
complete with picture, from John Rumm :

http://wiki.diyfaq.org.uk/index.php/2_Way_Switching#Switching_with_multiple_PIRs

I connected mine like this a year or so back. Got some single core
cable from an eBay seller to make the connection. It works a treat.