Final answer:
Alarm wiring in new construction should follow a three-wire system providing both a neutral and ground connection to protect against hazards with careful adherence to local color codes for wire insulation.
Step-by-step explanation:
When prewiring a new construction for an alarm system, it is essential to run alarm wiring following the guidelines of a three-wire system. This system includes a live/hot wire, a neutral wire, and a ground wire. The three-wire system enhances safety by providing a ground that guards against thermal and shock hazards. The neutral wire is connected to the earth at both the voltage source and at the user location, ensuring it is at zero volts and offers an alternate return path for the current.
Additionally, the case of the appliance is also grounded to zero volts. A circuit breaker or fuse is included in series on the live/hot wire to protect against thermal overload. It is important to note that wire insulation colors can vary by region. Therefore, it is crucial to be aware of local codes and to verify which color codes are being followed in the installation you are working on.