7251DH Datasheet, PDF (1/2 Pages) Systemsensor advanced ideas. – High Sensitivity Duct Smoke Detector

7251DH
High Sensitivity
Duct Smoke Detector
The System Sensor 7251DH detector is designed for
interior duct applications where high velocity, high
volume air changes are required for very early warning
fire protection.
Features
• Temperature range 32°F to 100°F (0°C to 38°C)
• Air velocity rating from 300 to 4,000 FPM
• 24 VDC operation
• Easy and quick mounting to round or rectangular ducts from
1 ft to 12 ft (0.3 m to 3.7 m) wide
• 3 year warranty
Agency Listings
S911
The 7251DH high sensitivity duct smoke detector provides
dependable performance for management of fans, blowers, and
air conditioning systems by using an intelligent laser smoke sensor
residing in an efficient housing design that samples air currents
passing through a duct. The twist-in, twist-out 7251 high sensitivity
laser smoke detector head allows easy removal for quick cleaning,
maintenance, and replacement without removing the duct housing.
The laser detector achieves sensitivities as low as 0.02 percent-per-
foot by using a laser diode instead of a standard LED light source
in the sensing chamber. Many sensitive areas cannot tolerate even
small amounts of smoke. This 7251DH detector is designed to
protect valuable assets and operations where systems must remain
online at all times.
Some ideal applications for the 7251DH high sensitivity duct smoke
detector include:
­­– Telecommunications switching facilities
– Cellular telephone infrastructure
– Integrated circuit fabrication facilities
– Computer rooms
– Clean rooms
NFPA 76, Section 8.5.3.1.2.3 Very Early Warning Fire Protection, calls for
sensors to be mounted at the return air location for a space in the
following instances.
(A) “Where stand-alone packed HVAC units are installed, sensors or
ports shall be installed where return air is brought back to the unit.”
(B) “Sensors or ports shall be installed such that each covers no
greater than 0.4 m² (4 ft²) of the return air opening.”
The System Sensor 7251DH high sensitivity duct smoke detector is
designed to satisfy NFPA 76 for Very Early Warning Fire Protection.