Answer: The pulse count is the amount of temperature changes the PIR will allow before going into alarm.

Answer:  The pet immunity is contingent upon the height of the animal.  The animal must be under 16 inches.
Changing the pulse count may help with cats sprawling.
 

No.  Normally open contact terminals are available on the outdoor PIR's.

Answer: Advanced temperature compensation will increase detection capability under high temperature conditions where the background temperature  
is similar to that of a human body.It maintains a high level of false alarm protection.
 

The DX40 Plus has an Alarm Memory and a Trouble Output.

Sensitivity L-Low is for when the enviroment is very stable
Sensitivity M-Medium is for when the enviroment is a normal
Sensitivity H-High is when the enviroment is very unstable