System Sensor for use with Johnson Controls systems. If you install this detector for someone else to use, leave a copy of this document with the user. Before you install any DH400 air duct smoke detectors, read and be familiar with: the control panel system installation manual...
These actions can facilitate the management of toxic smoke and fire gases throughout the areas served by the duct system. DH400 detectors are designed to operate with 12 or 24 Volts Direct Current (VDC) UL Listed compatible 2-wire control panels. The alarm current must be limited to 100 mA or less by the control panel.
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Table 4: Sampling Inlet Tubes Required for Different Duct Widths in the Mounting, Install the Sampling Inlet Tube section of this technical bulletin. Conventional Products—DH400 Conventional Air Duct Smoke Detector 5...
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4 to 8 ft (1200 to 2400 mm) ST-10 8 to 12 ft (2400 to 3700 mm) Exhaust Tube Extension A2440-00 5.75 in. (146 mm) additional Continued on next page . . . 6 Conventional Products—DH400 Conventional Air Duct Smoke Detector...
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Alarm current must be limited to 100 mA or less by the control panel. If used, the RA400Z remote lamp operates within the specified alarm currents. Reset Voltage 2.50 VDC Minimum Reset Time 0.3 sec. Maximum Startup Time 34.0 sec. Maximum Conventional Products—DH400 Conventional Air Duct Smoke Detector 7...
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7. Perform the detector check. 8. Install the cover. Verify Duct Model DH400 detectors are designed to be used in air handling systems Airflow Direction having air velocities of 300 to 4000 feet per minute. Be sure to check and Velocity engineering specifications to ensure that the air velocity in the duct falls within these parameters.
4. Put one 5/16 inch O-ring over each of the two No. 10 sheet metal screws. 5. Use the two sheet metal screws to screw the detector housing to the duct. 6. Do not overtighten the screws. 10 Conventional Products—DH400 Conventional Air Duct Smoke Detector...
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Table 4: Sampling Inlet Tubes Required for Different Duct Widths Outside Duct Width Inlet Tube Required 1 to 2 ft ST-1.5 2 to 4 ft ST-3 4 to 8 ft ST-5 8 to 12 ft ST-10 Conventional Products—DH400 Conventional Air Duct Smoke Detector 11...
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Sampling tubes over three feet long must be supported at the end opposite the duct detector. 3. Slide the tube into the centermost housing bushing. 4. Position the tube so that the arrows point into the airflow. 12 Conventional Products—DH400 Conventional Air Duct Smoke Detector...
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8. Plug this end with the end plug. 9. Tape close any holes in the protruding section of the tube. 10. Be sure to seal the duct when the tube protrudes. Conventional Products—DH400 Conventional Air Duct Smoke Detector 13...
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3. Space the additional holes as evenly as possible over the length of the tube. This procedure should only be used in an emergency; it is not intended as a permanent substitute for ordering the correct length tubes. 14 Conventional Products—DH400 Conventional Air Duct Smoke Detector...
* S pring clos es wh en detec tor head is rem ove d from m ountin g bas e. The installed hea d opens the sp ring, but internally prov id es a s hort c irc uit between the two term inals . Figure 6: System Wiring Diagram for 2-Wire Duct Detectors (Detectors Powered from the Initiating Circuit) Conventional Products—DH400 Conventional Air Duct Smoke Detector 15...
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Note: Do not loop the wire over the clamping plate. 4. Tighten the clamping plate screw. DH400 detectors are designed to operate with 12 or 24 VDC UL Listed 2-wire compatible control panels. Alarm current must be limited by the control panel to 100 mA or less.
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System Sensor. Inlet Sampling Tube Foam Gasket Sampling Tube Detector Base Mounting Screws Exhaust Filter Adapter Detector Head Sampling Tube Filters dhfig13 Figure 8: Sampling Tube Filter Installation Conventional Products—DH400 Conventional Air Duct Smoke Detector 17...
3. Make sure the cover fits into the base groove and all gaskets are in their proper positions. 4. Tighten the four cover screws to 10 in·lb. 18 Conventional Products—DH400 Conventional Air Duct Smoke Detector...
3. Blow smoke such as cigarette, cotton wick, or punk directly at the head to cause an alarm. 4. Remember to remove the plugs after this test, or the detector will not function properly. Conventional Products—DH400 Conventional Air Duct Smoke Detector 19...
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H ea d Tw ist C oun terclockwise to Re m ove D uct H ou sin g T w ist C lockwise to Install d hfig 8 a Figure 10: Detector Head Removal 20 Conventional Products—DH400 Conventional Air Duct Smoke Detector...
RTS451 Remote Test Station Technical Bulletin in the Intelligent Products section of this manual. Note: The DH400 duct detector must be reset by the system control panel. To install the RTS451: 1. Connect the device (Figure 10).
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S u p p ly) d hfig1 7 Figure 11: Wiring Diagram for RTS451 Remote Test Station to 2-Wire Duct Detectors Test Coil Detector Head dhfig14 Figure 12: RTS451 Test Coil Installation 22 Conventional Products—DH400 Conventional Air Duct Smoke Detector...
10. Remove the card and reset the detector at the system control panel. 11. Put the cover back by gently rotating it clockwise until it locks in place. 12. Secure the duct housing cover using the four cover screws. Conventional Products—DH400 Conventional Air Duct Smoke Detector 23...
3. If filters are heavily coated with dirt, replace them with new filters. 4. If they are not heavily coated, use a vacuum cleaner or compressed air nozzle to remove dust. 5. Reinstall the filters. 24 Conventional Products—DH400 Conventional Air Duct Smoke Detector...
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5. Brush or vacuum inside the area of the cover. 6. Then blow out the cover using clean, compressed air. 7. Vacuum the sensing chamber before using clean, compressed air to loosen and blow out any remaining debris. Conventional Products—DH400 Conventional Air Duct Smoke Detector 25...
3. Perform a detector check as described in the Perform Detector Check section of this technical bulletin. 4. Notify the proper authorities that maintenance has been completed and the smoke detector system is operating again. 26 Conventional Products—DH400 Conventional Air Duct Smoke Detector...
Date Installed Type and Model Number of Detector Head Description of Detector Location Table 6: Test Results and Maintenance Data Sample of Date Tested Test Test Results Maintenance Comments Test Log Description Performed Conventional Products—DH400 Conventional Air Duct Smoke Detector 27...
NFPA Standards 90A-Installation of Air Conditioning and Ventilation Systems Standard, 72-National Fire Alarm Code, and 101-Life Safety Code, or equivalent codes and standards specific to the country of installation. The DH400 air duct smoke detectors are listed per UL 268A. Controls Group FAN 408 507 E.
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