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#68978 - 08/22/06 10:49 PM Fire Alarm System
Cinner Offline

Registered: 12/01/04
Posts: 77
Loc: Kelowna, B.C., Canada
Has anyone encountered a very old fire alarm system that has a seperate 2 wire circuit with an EOL at each device? I am working on an existing fire alarm system that runs 2 wires in(red and black) and 2 wires out to next pull station or to the end of line resistor...but it also has a second circuit ( 2 blue wires) to each pull station with a different eol resistor at each pull station.

Does anyone know what the 2 blue wire circuit is and why there is a EOL at each device?

[This message has been edited by Cinner (edited 08-23-2006).]

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#68979 - 08/23/06 08:59 AM Re: Fire Alarm System
mikesh Offline

Registered: 06/07/06
Posts: 614
Loc: Victoria, BC, Canada
Is it a 2 stage Fire Alarm? Are there key switches at the pull stations in addition to the regular switch?

Maybe some auxilliary control for FA initiation by Pull station like a door holder or lock?

Secure the control cabinet and bell circuits. arrange a time to pull a breakglass and see what happens.

#68980 - 08/23/06 03:22 PM Re: Fire Alarm System
togol Offline

Registered: 09/15/05
Posts: 426
Loc: NW In. USA
it may be a supervisory circuit, but I am not certain...might be used to pinpoint which station is in alarm alarm

#68981 - 08/25/06 04:08 PM Re: Fire Alarm System
deverson Offline

Registered: 03/07/05
Posts: 20
Loc: Mosinee, WI USA
The blue wires are probably for the glass break feature. If you break the glass rod you get a trouble. I haven't seen one in a few years but used to deal with them weekly.


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