Directed Electronics 550ESP Automobile Alarm User Manual


 
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©
1999 Directed Electronics, Inc.
Your system has DEI's Nuisance Prevention Circuitry
(NPC
). It pre-
vents annoying repetitive trigger sequences due to faulty door pin
switches or environmental conditions such as thunder, jackham-
mers, airport noise, etc.
Example: The alarm triggers three times. Each time, the same sen-
sor or switch is triggering the alarm. The three triggers are within
60 minutes of each other. NPC
will interpret this pattern of trig-
gers as false alarms. After the third trigger, NPC
ignores, or
bypasses, that sensor or switch (along with any other sensors or
switches sharing the same zone).
If the bypassed sensor tries to trigger the security system while it
is being bypassed, the 60-minute bypass period will start over. This
ensures that a sensor that is continually being triggered will
remain bypassed.
The vehicle doors are protected by NPC
differently. If your securi-
ty system is triggered by an open door for three full cycles, the sys-
tem will bypass the doors until the trigger ceases.
NOTE: Arming and disarming the system does not reset this function! The
only ways to reset a bypassed zone are for it to not trigger for 60 min-
utes, or to turn on the ignition. If testing your system, it is important to
remember that the NPC
programming can cause zones to be bypassed
and appear to stop working. If five chirps are heard when disarming, NPC
has been engaged. If you wish to clear the NPC
memory, turn the igni-
tion on.
Nuisance Prevention Circuitry