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The Flexible FAI Input Has You Covered

At first glance our Fire Alarm Input (FAI) may seem a bit more complicated than the competition's, but when you know why and how it helps you in the field, it will quickly become your new best friend.

Traditionally, FAI inputs have been dry contact input only, and typically only accepted a NO contact or a NC contact, depending on the manufacturer or product.  There was no ability to change the type of input - if you had a NO-type FAI input and a NC contact from the fire panel, you had two choices:  call the fire panel installer to switch it to NO or install a relay between the FACP and the FAI input.

LifeSafety Power has you covered! The FAI input on the FPO power supply line is configurable for virtually any type of input out of the box.  It will accept a NO or NC dry contact, voltage input, open collector (transistor) input, or even a polarity reversal on a fire alarm NAC loop.  The key to its flexibility is in its wiring, which necessitates extra terminals in comparison to a traditional FAI input.

The FAI input of the FPO power supply has six terminals, which can be divided into pairs:

I+ and I- terminals are the actual input to the FAI circuit.  They are opto-isolated, accept a voltage from 9-30VDC, and are polarized to ignore a reverse polarity voltage as you would see in the standby state of a NAC loop.

V+ and V- supply an auxiliary voltage which can be used in conjunction with dry contacts or other methods for activating the I+ and I- terminals.  This voltage is current limited and if it shorts will only allow 10-15mA of current to pass.  This not only protects the activation contact, it allows this voltage to be shunted in the NC dry contact application.  If the V+ is connected to I+ and V- is connected to I-, the FAI input will activate (shown by the illumination of the red FAI LED on the FPO power supply).

The two L terminals allow latching of the FAI input.  This is required in some regions including areas of Canada.

Our application note AN-27 General FAI Usage can be used along with the FPO Power Supply instruction manual and PowerPro TV FAI Training Video to gain even more knowledge on the FAI input.  And as always, our Technical Support team is always here to help.