Xtralis VESDA VLC-505, Manual

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ASPIRE Software
VESDA Student Workbook 7-3
VEWFD
(Very Early Warning Fire Detection)
EWFD
(Early Warning Fire Detection)
SFD
(Standard Fire Detection)
Sensitivity at each port/ sensor 1.0% obs/ft. 1.5% obs/ft. 2.5% obs/ft.
Coverage
Open Area 200 sq. ft. 400 sq. ft. 900 sq. ft.
Return Air Grille 4 sq. ft. (Grille Area) Duct Detection Duct Detection
Transport Time 60 Seconds 90 Seconds 120 Seconds
• Detector sensitivity is determined by ASPIRE to be verified as per local codes.
• Smoke thresholds listed within the ASPIRE calculation are a guide only and are bound by a standard
range. Exact smoke thresholds setting are to be modified and made suitable for the environment in
which the detector in installed.
Example US:
NFPA 76
Designing, codes, and sensitivity classification
Aspirating Smoke Detection can provide VEWFD, EWFD or SFD detection capabilities to match or exceed minimum NFPA 76 requirements
SPE aggregate area > 2500 ft2(232 m2)
SPE aggregate area ≤ 2500 ft2(232 m2)
Signal-Processing Equipment (SPE)
Room/area detection
Raised floors with combustibles
– No common airflow above and below
Raised floors with combustibles - common airflow above and below
VEWFD
EWFD below floor
VEWFD above floor (room/area detection) EWFD
EWFD
EWFD
Cable Entrance Facility EWFD EWFD
Power Areas/Equipment EWFD EWFD
Main Distribution Frame Area (MDF)
Room/area detection
Raised floors with combustibles
– No common airflow above and below
Raised floors with combustibles - common airflow above and below
VEWFD
EWFD below floor
VEWFD above floor (room/area detection) EWFD
EWFD
EWFD
Standby Engine Area Heat or flame detection Heat or flame detection
Technical Support Areas (TSA)
TSA not part of telecommunications equipment area
TSA contiguous with SPE or MDF areas
TSA contiguous with power areas
TSA part of telecommunications equipment area when SPE area ≤232 m2 (2,500 ft2) SFD per NFPA 72
VEWFD
EWFD
Not Applicable SFD per NFPA 72
See below
See below
EWFD
HVAC Systems
If VEWFD is required for the space (see above) then provide VEWFD as noted in next column
VEWFD ports to monitor return air; VEWFD ports to
monitor returns of stand-alone packaged HVAC units
Not applicable
Designing and codes