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SECTION IV - SYSTEM DESIGN UL EX. 3470 ULC CEx747 Page 4-50 REV. 2 10-1-02 DETECTION SYSTEM REQUIREMENTS Once the fire suppression system design has been determined, a detection system design must be completed. This section contains guidelines and limitations for detection system installation. Detector Identification The two types of detectors are distinguished from each other by their location in the detection system. 1. The Terminal Detector (Part No. 56838, 15375, or 417368) is the last in a series of detectors, or the only detector used in a single-detector system. This detector is thus named because it is at the point at which the wire rope ends, or "terminates.w 2. A Series Detector (Part No. 56837, 15373, or 417369) is any detector located in-line between the regulated release mech- anism and the terminal detector. DetectorJPulley Elbow Quantity The quantity of detectors used in the system will vary depending on the style of detector used. 1. Conduit runs, pulley elbows, and number of detectors per sys- tem must be within the approved system guidelines. The fol- lowing requirements must not be exceeded: Maximum Maximum Number of Number of Detectors Elbows per System per System 12 18 Maximum Length of 1/2 in. Conduit per System 125 ft. (38.1 m) Clip on Style Detector Hinge Style Detector Scissors Style 15 Detector 2. If hinge style detectors are mixed in a system with either clip- on or scissor style, 4 series and 1 terminal is the maximum number allowed. If clip-on style are mixed with scissor style, the maximum allowed is 11 series and 1 terminal. 5 8 103 ft. (31.3 m) 20 150 ft. (45.7 m) NOTICE When using the "clip-on" style detector, the ter- minal detector may use the "hinged" style mounting bracket with the "clip-on" style linkage. This is only allowed with the terminal detector. . No other linkages are allowed to be mixed . with other brackets. When using this option, the total number of "c1ip-onw style detectors (11 series and 1 terminal) is still allowed. 3. If hinge style detectors are mixed in a system with either clip- on or scissor style, the maximum leng1h of wire rope must not exceed 103 ft. (31.4 m) and the maximum number of pulley elbows must not exceed 8. If c1ip-on style are mixed with scis- sor style, the maximum leng1h of wire rope must not exceed 125 ft. (3.81 m) and the maximum number of pulley elbows must not exceed 18. 4. If the hazard requires more than 15 detectors, up to five 101 Remote Releases (Part No. 12029) can be used for system actuation. Each 101 remote release allows the use of a maxi- mum of 15 "scissor" style detectors (14 series and 1 terminal) for a total of 75 detectors if needed. Detector Placement Requirements EXHAUST DUCTS Each exhaust duct must have at least one detector installed in the duct entrance, located in the airstream of the cooking vapors, or at · a maximum of 20 ft. (6.1 m) into the duct opening. See Figure 89. .-.-rn"''' --- --'-' ...... ~-_. 20 FT. (6 m) MAXIMUM l"'l ,........ . '---------------- . FIGURE 89 000271 NOTICE When gas appliances are used and the flue gases from the burner are exhausted into the duct, the detector must be kept out of the air stream of these exhaust gases. These gases can be very hot and could actuate the system unnecessarily. Duct openings that are long and narrow or large enough to require multiple duct nozzles may require additional detectors. ELECTROSTATIC PRECIPITATOR If an electrostatic precipitator is located at or near the base of tt)e exhaust duct, it is necessary to locate a detector below the pre- cipitator, at the base of the duct, and also locate one in the duct, . just above the precipitator. See Figure 90. When installing the detector bracket and system conduit, make certain they do not interfere with the operation of the precipitator. f . FIGURE 90 000208