What type of detectors should not be included in an intrusion system hardware option?

Normally open (NO) unsupervised detectors are typically not advisable for inclusion in an intrusion detection system due to their inherent vulnerabilities and limitations. These detectors function by being activated when a circuit is broken, which can often occur inadvertently or due to environmental factors, creating false alarms. Since they are unsupervised, there's no additional verification mechanism to monitor their status, making them less reliable compared to supervised detectors.

Supervised detectors, whether normally closed or otherwise, offer a level of self-checking that enhances security by ensuring that the system can detect whether the detector is functioning properly. Similarly, motion detectors with a delayed response serve a specific purpose by allowing authorized individuals to enter and exit without triggering an alarm unnecessarily, yet still provide protection against intruders.

Wireless battery-operated detectors have their own advantages, particularly in scenarios where wiring poses a challenge, but they also come with considerations regarding battery life and signal reliability. Ultimately, the inclusion of devices that provide adequate monitoring and verification, such as supervised detectors, contributes to a more robust and reliable intrusion detection system, as opposed to those that are prone to false alarms and lack supervision.