Fire Fighting Enterprises FIRERAY 2000 (Legacy) - Manual (Page 2)

Fireray 2000 Installation Guide 22318.00.R 25.08.05
2
System Description
The Fireray 2000 is a linear beam smoke detection system capable of protecting an open indoor area of up to
1500 square metres.
The System comprises a Transmitter which projects a modulated infrared beam over an area to a Receiver,
which then forwards a signal to a Control Unit for analysis. The System can detect smoke particles obscuring
the beam path. When obscured for a predefined length of time the Control Unit will generate an alarm.
Smoke Detection
When smoke is present in the beam path the signal received by the Receiver is reduced relative to the density
of the smoke. If the density of the smoke reduces the signal below a preset threshold for a period of 10 seconds
an alarm relay is activated.
There are 3 selectable threshold levels available, 25%, 35%, and 50%. (25% being the most sensitive).
Auto Reset
The alarm relay is configurable and can be either latching or non-latching.
If non-latching is selected the alarm relay will reset 5 seconds after the smoke has cleared.
If latching is selected the alarm relay will remain set until either a power down reset is performed, or the
Controller Unit receives an external reset.
Automatic Gain Control
The Control Unit supports an Automatic Gain Control (AGC) circuit. Long term degradation of signal strength by
the build up of dirt on optical surfaces will not generate an alarm because of compensation provided by the
AGC circuit. This operates by comparing the received signal against a standard over a predefined time interval
which is nominally 1.5 hours, if the signal strength deviates by more than 7% over this time span the Receiver
gain is automatically adjusted to compensate.
Fault Detection
The Control Unit is capable of detecting failures within the System. In the event of a System failure being
detected the fault relay is activated.
System failures will be caused by:
• The TEST/RESET switch in the Control Unit set to the ON position
• Total loss of power or a supply reduction below the specified minimum to the Control Unit.
• The System is unable to settle during the power on AGC stabilisation period.
• The System AGC circuits have reached the limit of compensation.
• The signal has been reduced by more than 93% for approximately 10 seconds.
• The beam path is completely blocked.
• A Transmitter failure.
• Loss of power to the Transmitter.
• A Receiver failure.
• Misalignment of the Transmitter and Receiver resulting in a signal loss of greater than 93%