Viper 320HV Owner Manual - Page 15

➜ Nuisance Prevention Circuitry (NPC)™ Your security system has Nuisance Prevention Circuitry™ (NPC™) to prevent annoying false alarms. This circuitry is designed to prevent repetitive trigger sequences due to faulty door pinswitches or environmental conditions such as thunder, jackhammers, airport noise, etc. Here's how it works: If the alarm is triggered by the same sensor or switch three times within a 60 minute period, your system interprets this pattern of triggers 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) for 60 minutes. If the bypassed sensor is triggered again while it is already being bypassed, the 60-minute bypass period will start over, ensuring that a sensor that is continually being triggered will remain bypassed. The vehicle doors are protected differently by NPC™. If your security system is triggered by an open door for three, full 30second cycles (one and one half minutes), the system will bypass the doors until the trigger ceases. NOTE: Arming and disarming the system does not reset the NPC™. The only ways to reset a bypassed zone are for that zone not to be triggered for 60 minutes or to turn the ignition key on. When testing your system, it is important to remember that NPC™ can cause zones to be bypassed and appear to not work. If five chirps are heard when disarming the system, NPC™ has been engaged. To clear the NPC™ memory, simply turn the ignition key on. 12 © 2004 Directed Electronics, Inc.