Reference · Design
Alarm Current
Current drawn with all notification appliances and relays active. Multiplied by alarm minutes (as a fraction of an hour) in a battery calculation and used for NAC voltage-drop sizing.
NFPA 72: 10.6.7.2, 18.3
Section numbers vary by edition — confirm in the edition your AHJ has adopted.
Read more in these guides
Fire Alarm Battery (Standby) Calculation BasicsSecondary batteries keep a fire alarm running when the power fails. Here's how standby battery sizing works, in plain language.Fire Alarm Voltage Drop, ExplainedThe last strobe on a long circuit sees less voltage than the panel supplies. Here's why voltage drop happens and how designers stay within limits.