EWIS
How long will my fire panel battery last?
I have been asked to discuss the reasons why we recommend the installation of a second (tertiary) set of backup batteries installed in parallel to the existing main (secondary) batteries installed within a fire panel during a planned mains power shut down.
The building owner contacted us to advise they plan to shut down the power to their building for a period of 8 - 12 hours for maintenance purposes. The planned shut down will also remove mains power from the fire panel.
There is a small fire panel installed on site designed to Australian Standard AS1670.1-2004, fitted with an occupant warning system.
In this example the customer wanted to know if it is necessary to install tertiary backup batteries.
How to measure EWIS or PS speaker zone impedance
Impedance is a measure of the opposition to the flow of an alternating current in a circuit; the aggregation of its resistance, inductive and capacitive reactance. Represented by the symbol Z.
AS1670 Calculating Power Supply Requirements for Fire Alarm Systems
3.16 POWER SOURCES
3.16.1 Primary power source
The CIE shall be energized by a reliable source of supply and shall be connected in accordance with AS/NZS 3000. The power source shall be either?
(a) an a.c. supply from an electricity authority; or
(b) a source equal in quality and reliability to Clause 3.16.1(a). The primary power source shall be capable of operating the system including the occupant warning system as per Clause 3.22(b).
3.16.2 Secondary power source
Maintenance Procedures for Emergency Warning & Intercommunication Systems
The maintenance of Emergency Warning & Intercommunication Systems is generally carried out according to the following standards;
Emergency Warning & Intercommunication Systems
An '''Emergency Warning and Intercommunication System (EWIS)''' is a piece of equipment in buildings that helps to save lives when used in conjunction with appropriate ''Emergency Procedures (EP)''.
