There is no need for the interconnect conductor, as Nest
Protects are wirelessly interconnected. If you are replacing all
of your alarms with Nest Protects, connect all of the
interconnect conductors to earth. If you are keeping some of
your current alarms, they won't be able to connect to Nest
Protect, but they'll still need the interconnect conductors to
communicate with each other. Connect the interconnect
conductors together with their own connector block. You may
need an additional connector block.
Be sure that you comply with local wiring regulations in your
area.
Warning: Mixing the live and neutral connections when
connecting alarms will damage all the alarms - ensure that the
same colours are used throughout the premises for live, neutral
and interconnect wires (if present).
Screw the Nest back plate to the existing electrical box, reusing
the existing screws. (You can also screw the back plate directly
into the wall or ceiling with the Nest screws.) The Nest screws
are self-tapping, so there's no need to drill pilot holes in wood,
plaster and other relatively soft materials.
Tip: All smoke alarms prefer to live in a dust free area, so
remove any dust before you install Nest Protect.
