Perhaps the most important aspect associated with life safety, as it pertains to fire detection, is secondary power.
Standby Time Range Is 24-60 Hours
Take, for example, the public electric bus. If it should fail, the batteries you used when the system was newly installed must be capable of maintaining the system in standby mode for a given period of time, with a subsequent ring time of at least 5 minutes.
Specifically, when the fire alarm system in question is classified as a protected premises, central station or proprietary system, the required standby time, according to Section 1-5.2.6, NFPA 72, 1999 Edition, is 24 hours. When the system is classified as an auxiliary or remote station fire alarm system, the standby time is 60 hours.
Testing Helps Ensure Compliance
One way to help assure compliance of Section 1-5.2.6 is to test your client’s fire alarm system batteries at every opportunity. The best way to do this is to use a high-tech battery capacity checker, like the ELK-BLT v.2 Mhos Meter manufactured by ELK Products Inc. of Hildebran, N.C.
The ELK battery checker is scientifically designed to test the conductivity of batteries, as measured in Mhos (the inverse, or reciprocal of Ohms). In addition, it will automatically indicate the present potential difference generated by the battery, measured in direct current (DC) volts.
Using a Battery Testing Device
To test a battery using the ELK battery tester, simply disconnect the battery from the alarm panel and connect the test leads. Place the red lead to the positive terminal and the black lead to the negative. The built-in, solid-state display will automatically show volts and then Mhos.
The ELK device comes with a plastic carrying case and a set of battery test labels on which the date, voltage, Mhos and technician’s name are placed. The label is then fastened to the battery or batteries.
Al Colombo is a technical writer in the electronic security and fire protection markets, providing technical direction for security dealers since 1986. Send your fire-related questions and comments to [email protected].