If you have been running the turbo(s) you should let the engine idle before switching ignition off. They monitor how hard you have been running and after you have switched the ignition off , the timer keeps the engine running accordingly.
I just use my head and leave it idling for a minute or so
Not needed then
Turbo timers are not always necessary if you allow the car to idle for a minute or so before switching off. When I still had the Clifford alarm the car was set to idle for 60 secs (or whatever you wanted) after the key was pulled out. This meant that I could also lock the car while it still idled and walk away.
With my current turbo timer, unfortunately I have to sit it out (the idling) before I can lock the door and arm the system. Damage to the turbo can be caused if they are not allowed to 'cool' down first. Somebody more technical could give you the precise details as to how the turbos can 'cook' themselves if left to stand whilst hot. I don't know the actual mechanics of it - just been told that damage will occur.
I had the 500 in at the time and was fairly useful with the turbo set timer built in. However (and I think others have observed this) the Clifford sensors need careful positioning as they can be easily set off by all sorts of things. Having said that an oversensitive alarm is probably better than one that doesn't react
Plus when my car was broken into (when the Clifford was still in) they never got the vehicle to start, so they can't be bad!