Fire Fighting Enterprises FIRERAY 2000 EExd - Manual (Page 5)

Page 5 of 12

During installation, no threshold switch set at the Controller Unit (One switch only must be set).
Possible Causes Of FIRE And FAULT Alarms Together

AGC at limit of compensation, COMP switch OPEN (UK installations only) and beam strength
reduced by more than the set threshold.
PRECAUTIONS WHEN INSTALLING THE SYSTEM
Always ensure that the hazardous area into which the system will be installed is safe to work in, and that
neither you nor the installation will compromise the safety of that area.
Ensure that all mandatory and local regulations, regarding both fire alarm systems and EExd, IIB
applications, are adhered to.
Choose solid, stable surfaces on which to mount the Receiver and Transmitter.
If one of the mounting surfaces for the Transmitter or Receiver is likely to be susceptible to movement,
always mount the Transmitter on the more stable surface. The Receiver is less affected by mis-
alignments.
The beam should be positioned approx 30cm to 60cm below the ceiling, to avoid smoke layering or
masking effects.
Take precautions to position the beam such that it cannot be blocked during the normal course of
operations in the building.
Avoid mounting near or over heaters systems etc. Heat haze may cause obscuration and high levels of
beam ‘noise’.
If possible, avoid areas subject to thermal ‘shock’, such as near external loading bay doors etc. If
condensation forms on the lenses, this will be seen as an obscuration.
Avoid high intensity lighting near the receiver lens and avoid angling the Receiver directly at the sun.
The system incorporates circuitry to minimise effects due to high levels of ambient light (>15000 Lux),
but over heating of internal parts may occur with very strong sources, due to the focused beam within
the Receiver.
If possible, avoid bunching the system cables with factory power or other cabling.
To achieve maximum EMI rejection, use screened cables for the system wiring, properly terminated at
metal glands (Do not use screen pigtails). MICC cable is recommended.
Use the correct EExd approved cable gland types for all system parts in the hazardous area.
Cables must be suitable for a minimum temperature of 101°C.
SETTING UP AND ALIGNING
The Transmitter and Receiver heads must be positioned on stable, solid facing surfaces, such as
parallel walls, approx 0.3m to 0.6m below the area ceiling (See application notes near the end of this
guide). The surfaces must be parallel, vertically and horizontally within approx 20 degrees, although a
greater positioning range is possible (up to 40 degrees off line-of-sight) if the Receiver is also fitted it
with an Adjustable Mounting Bracket. This is available as an optional extra. If only small adjustments
are required, the Receiver line-of-sight may be adjusted by fitting spacer washers to its wall fixing