I have a dual air conditioner, an external machine for two internal equipment. Can I use a single P1?

You need a occupancy sensor for every internal unit you have.

Every occupancy P1 will control the room where is installed in, and it will swicth off the relative (and paired) internal AC unit.

If you want to control 2 different rooms, each rooms with his own air conditioning, then you need 2 occupancy P1, one for every AC.

Also note that Occupancy Sensor P1 have a special feature: "Apartment mode".
With this mode, you can control 2 or more motion sensor for air conditioner with a single "door Sensor".

Read more about our motion sensor for air conditioner P1 models here.