Edwards Signaling FSC Series - Manual (Page 84)

Appendix A: System calculations
76 FSC Series Technical Reference Manual
The minimum voltage is the lowest voltage measured at the NAC terminals when
the power supply is under the maximum load for that circuit (i.e. for the
appliances that constitute the NAC).
The voltage drop is the difference between the minimum voltage and 16 V. This
value is for use with the worksheet only.
Worksheet method
Use this worksheet to determine the maximum cable length of a notification
appliance circuit for a given number of appliances.
Use this worksheet only if all the appliances are regulated. That is, they must
have a minimum operating voltage of 16 V. For other appliances, use the
“Equation method.”