All tools
NEC Chapter 9
NAC Voltage Drop Calculator
Check the end-of-line voltage on a notification appliance circuit.
Enter the circuit values to see the end-of-line voltage.
Check the listed appliance's datasheet — this varies by manufacturer and model, it isn't a fixed code number.
A necessary note. This uses NEC Chapter 9 Table 8 DC resistance values and assumes the full
connected load runs the entire one-way distance — the conservative "worst case" method used
for a quick field check, not a precise segment-by-segment calculation for devices spread along the
run. This tool is a planning aid, not a substitute for a code review by a licensed design
professional or your authority having jurisdiction, and it does not replace the manufacturer's own
voltage drop calculation for the specific panel and devices installed.