Most of us today realize the necessity of having at least basic home fire alarm detectors in our homes as well as had them installed. In their simplest form, the units are plastic, free-standing boxes run by a battery. They are able to detect smoke and then sound a loud siren to warn people of danger.

There’s no doubt that fire alarms save lives, but only when they’re in working condition. All too often alarms fail and tragedy occurs. Statistics show that the number of fire alarms that fail in critical situations is around 30%. That’s one out of three, man!

Fire Alarms Operate on the Same Basic Concepts

Today they are hundreds of different fire alarm systems on the market. You can find inexpensive do-it-yourself models all the way up to complex home fire alarm systems. All of these operate on either NPLFA or PLFA circuits. These special circuits have been designed to keep the circuit broken unless a fire or smoke alarm sounds. Only then will the electric circuit be completed.

Special fire circuits are so sensitive that it almost seems like they can "see" smoke. This is especially true when the fire is a smudge that generates a lot of smoke. Some units respond to big changes in temperature in short periods of time. Any time the system senses a temperature change, a fire alarm circuit is broken which causes an alarm to sound.

The fire alarm circuit you choose should have a Notification Appliance Circuit expansion to provide auxiliary power to the various accessories to the system. Factors that should impact your choice include price, user preferences, and site requirements. You’ll be able to find a basic unit for under $50. More comprehensive systems may run as high as $300. These systems are made by companies you know and trust such as Altronix, Fire-Lite, and Kidde.

Both the NPLFA and the PLFA fire alarm circuits can work at up to 600 volts. The NPLFA is not limited by a power source whereas the PLFA is limited by a number of things, including over current protection, wiring methods, the size of the conductor as well as the amount of insulation it has.

It’s all up to you to compare and contrast the two fire alarm circuits which are available and decide which will be best for your needs. There’s no better feeling than knowing you’ve protected your family.