Concerning the illustrated fire detection...

Concerning the illustrated fire detection and alarm system, what statement is true concerning the wiring within a zone? See illustration EL-0114.

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🔍 Key Concepts

• Carefully trace the zone wiring from the terminals to circuits (1–10) over to the manual station, closed‑circuit thermostat, and test station symbols. • Review how a closed‑circuit fire detection system is normally arranged so that a broken wire or removed detector will give a trouble or alarm condition, not silence the circuit. • Compare what series vs. parallel wiring would do to current flow in the zone during (1) normal condition, (2) detector/manual activation, and (3) open‑circuit fault.

💭 Think About

• From the drawing, do all devices in the zone share the same current path one after another, or does each device have its own separate branch between the same two conductors? • In the normal (no fire) position, are the contacts for the thermostat and manual station shown made or open? What must happen to those contacts to cause current change and operate the alarm relay? • If one detector in the zone were physically removed or a wire broke, would the rest of the detectors still be able to operate the alarm, or would the whole loop go dead? How does that relate to closed vs. open contacts in normal service?

✅ Before You Answer

• Verify on the illustration whether the thermostat is explicitly labeled "Closed Circuit Thermostat" and note the contact position shown. • Confirm whether the drawing shows one continuous loop through all thermostats/manuals/test station for a zone (series) or multiple branches connecting across the same two zone conductors (parallel). • Before choosing, match the option you like to BOTH of these: (1) the actual contact symbols on the print (normally open or normally closed), and (2) the behavior you’d expect from a fail‑safe fire detection circuit where an open wire cannot silence the system.

🔍 Key Concepts

💭 Think About

✅ Before You Answer