Types of Alarm Systems.

Block Plans (Ref BCA E1.8 AS 1851, AS 1670, AS 3745).  In every Fire indicator Panel (FIP) there will be two sets of block plans.  These block plans give the fire service and the Emergency Control Organization (ECO) the information they require in regard to the fire safety systems installed in the building.  These block plans indicate the whereabouts in the building as to which alarm has been activated, either by zone or each individual detector, this would very much depend of which type of alarm system that has been installed.  The Block Plans bear a legend that will indicate the different types of detectors together with the locations of these detectors within the building.

Power Failure.  Most alarm systems operate on 24V DC, converted from 240V AC.  The batteries must have the capacity to power the Control Indicating Equipment (CIE) for 24 hours in a no alarm condition and for ½ hour during an alarm situation.

 

Romteck – This is the alarm transponder unit that automatically sends a signal to the Fire service once an alarm has been activated in the building.  Note if the alarm is generated manually via the EWIS there will be no signal sent to the fire service.  This unit also allows maintenance to be carried out on the alarm system by turning the key to test, in this position the key cannot be removed and the FIP door will not close.Types of Alarm Systems.

 

Collective.

Addressable.

Analog.

Intelligent.

 

(Ref BCA E2 and E4 AS 1851, AS 1670).

Collective systems – These systems are widely used today which are very effective and easy to understand.  They can connect a maximum of 40 detectors to an individual Alarm Zone Facility (AZF).  When one of these detectors senses the presence of smoke, heat, flame etc an alarm will be generated via the FIP.  The FIP will include a light indicating the particular zone in which the alarm has been activated. This will ultimately generate an alarm that could call the fire service, alert all occupants, start smoke management systems and close fire /smoke doors etc.

 

 

 

 

 

 

 

 

  

This photo demonstrates that AZF 4 has been activated.  The block plan below indicates that it is one of the smoke or heat detectors in the eastern side of the building.

 

 

 

Addressable – These types of systems use the wiring as a digital communications link to the FIP with each individual detector.  The detectors wired to these systems can send its status to the FIP for example, Fault, Normal or Alarm.  There are two main advantages to these systems, is that�� detectors can be connected into a single loop.  The Fire service and  or the ECO can identify the detector by the unique address within the building, this saves time looking for the location of the fire.

 

The photo below explains an example of an activation of a smoke detector, Alarm Zone 12 (AZ12) on Level 2 (L2) Smoke detector 59 (S59). = AZ12-L2-S59.

 

 

 

Get the picture?  (Easy when you know how).

 

Analog systems – These are very similar to the addressable systems however the detector acts as a sensor which is designed to send a digital signal to the FIP, for example the temperature, smoke concentrations or IR/UV levels.  From this information the FIP can compare the data against pre set thresholds and generate the alarm.

Intelligent systems - These are the same as the Analog systems however the FIPs decision to generate the alarm will be by means of examining the fire signature.