its nothing to do with how many times you turn the key.
the 3 beeps simply means the ECU is still receiving a signal from the ignition, so the alarm beeps to let you know it can't be set yet. It will set shortly after the beeps. There's a Renault fix for it you can get done at a dealer.
Saying that, I believe there's a way to disable the internal motion sensors.
It is Dan, yeah. If I want to leave windows open, or wash the car;
-turn off ignition
-open door
-put key in ignition and turn to stage two and back again twice
-take key out
-close door and lock as normal.
Alarm will beep three times and lock. Means the internal sensors are off. Can be done for things like dog/children in the car as well.