In wiring an additional fire alarm to an existing power source, when is a T-branch/splice acceptable?

In wiring an additional fire alarm to an existing power source, when is a T-branch/splice acceptable?

• A. Always
• B. Sometimes with proper approval
• C. Never acceptable
• D. Only by licensed electrician

Answer: (C)

Tapping into a fire alarm power source with a simple T-branch or splice is not allowed because it can compromise the circuit’s supervision and reliability. Fire alarm circuits are designed to be monitored by the control panel, and ad hoc taps can create unmonitored branches, voltage issues, or fault pathways that the system cannot properly detect or report. This can lead to missed alarms or false activations, and it may violate listing and code requirements. The correct way to add a device is to use a listed power-tap or a dedicated power supply that’s approved for fire alarm use, installed per the manufacturer's instructions and local codes, with the work performed by a licensed electrician and approved by the authority having jurisdiction. That’s why a plain T-branch/splice is considered unacceptable.

Tapping into a fire alarm power source with a simple T-branch or splice is not allowed because it can compromise the circuit’s supervision and reliability. Fire alarm circuits are designed to be monitored by the control panel, and ad hoc taps can create unmonitored branches, voltage issues, or fault pathways that the system cannot properly detect or report. This can lead to missed alarms or false activations, and it may violate listing and code requirements.

The correct way to add a device is to use a listed power-tap or a dedicated power supply that’s approved for fire alarm use, installed per the manufacturer's instructions and local codes, with the work performed by a licensed electrician and approved by the authority having jurisdiction. That’s why a plain T-branch/splice is considered unacceptable.