Fire Alarm Battery & PSU Calculator

The app calculates the required Battery size and Power Supply for an installed Fire Alarm system, this includes the Fire Panel and all connected zones plus all ancillaries & outputs. The Power Supply is required to charge the battery to 90% within 24Hrs after a full discharge.

Iq is the quiescent current of the system running only on battery, the reading taken with a suitable clamp meter or in series amp meter.

Ia is the full load current of the system with at least 2 alarm zones activated + all ancillaries and outputs activated, readings taken as with Iq readings.

Pressing the 24, 72 or 96 hour buttons produces the battery sizes for the system.

To calculate the power supply size you first need to check if the system has any ANCILLARIES that are not connected to the battery supply, these ancillaries are not part of the battery requirements BUTT are required for the power supply calculations.

When calculating the PSU size press the button relative to the larger value of Ia or Iq.

The app is also capable of calculating the Power Supply requirements for the systems Emergency Warning Intercom System

Take the same Iq Ia readings with Ia at full load, then place the resulting calculation in the EWIS section of the app. You can use the nearest standard battery size that exceeds the results or if the system battery is equal to or greater than the required size it can be used.

NEW in this app is now the FIP PSU calculator, calculates the power supply requirements for each 24Hr, 72Hr and 96Hr systems.