Which is true of the phone lines on a Digital Alarm Communicator Transmitter (DACT) when...

When aDACTis the only method of off-premises signal transmission, itmustbe connected totwo separate telephone linesto ensure redundancy in case one line fails.

NFPA 72 (2022), Section 26.6.4.4.4.1:

“DACTs shall be connected to two separate phone lines (one primary, one secondary). Loss of the primary line shall result in a supervisory signal.”

This redundancy ensures system reliability when using traditional telephone-based communication.

Correct answer: D. Two separate phone lines are required

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