Final answer:
In a double-loop Fenwal system, the detector units are wired in parallel with each other, creating two complete circuits that both start and end at the control panel. This design is aimed at maximizing safety by ensuring that even if one loop fails, the other will still function.
Step-by-step explanation:
The detector units in a double-loop Fenwal system are wired in a very specific way to maximize effectiveness and safety. In this fire detection system, the detector units are wired in parallel with each other, forming two full loops for continuity. Each of these loops is designed to begin and end at the control panel. This double-loop design is meant to ensure that a fault or break in one loop does not interrupt the operation of the other, maintaining the integrity of the system. In case one loop is damaged, the other loop serves as a backup, allowing the system to continue functioning properly and providing an extra layer of safety.
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