Smoke and Fire Detector Models 8900, 8901, 8902, and 8903 - Installation and Wiring Instructions

Oct 29, 2026

Installation and wiring instructions for smoke and fire detector models 8900, 8901, 8902, and 8903, including end-of-line polarity guidance and wiring for listed remote lamps 8922 or 8923 at 24V. The guideline covers NFPA 72 and NFPA 90A compliance, recommended detector placement on ceilings or walls with clear distance rules, and follow-verified drawings. It explains how to avoid nuisance alarms, considers air currents, ceiling obstructions, temperature and humidity limits, pressure effects at altitude, and provides application guidance by model and airflow velocity range.

LanguageEnglish

CategoryHealthcare

FormatPDF

Pages4

Reading Time10 min

AccessFree to download

Detector placement

Avoiding nuisance alarms

Air currents

Special ceiling construction factors

Temperature and humidity

Pressure

Applications

Installation/Wiring Instructions Smoke and Fire Detector Models 8900, 8901, 8902, and 8903 End-of-line device observe polarity if applicable Connection for listed remote lamp 8922 or 8923, 5mA mas, at 24V (one per detector.) †NOTE: The Models 8900, 8901, 8902, and 8903 are rated at 16-25 .7 VDC—3 volt peak to peak maximum ripple. Supervisory current 110µA max steady state. 350µA peak surge upon application of power, and 135mA max in alarm. Figure 1 Models 8900, 8901, 8902, And 8903 Installation And Wiring Diagram P/N 315-081882, Rev. 2 THIS INSTALLATION GUIDELINE IS WRITTEN IN ACCORDANCE WITH THE INSTALLATION GUIDELINES OF NFPA 72, STANDARD FOR AUTOMATIC FIRE DETECTORS, AND NFPA PAMPHLET NO. 90A, AIR CONDITIONING AND VENTILATING SYSTEMS. DETECTOR PLACEMENT Although no specific spacings have been allocated for the detectors used for the 0 to 300 ft/min clean air velocity application, 30 foot center spacing (900 sq ft) as referrred to in NFPA Standard 72 Detectors, may be used, if practical, asa guide or starting point for a detector installation layout. This spacing, however, is based on ideal conditions — smooth ceiling, no air movement, and no physical obstructions. In some applications, therefore, considerably less area is protected adequately by each smoke detector. This is why it is mandatory to closely follow the installation drawings. In all installations (except in special circumstances, such as in computer room underfloors where the velocity may be between 300 and 1200 ft/min) the detector should be located on the ceiling, a minimum of 6 inches from a side wall, or on a wall, 6 inches from the ceiling. Should questions arise regarding detector placement, drawings provided or approved by Faraday or by its authorized distributors should be followed. This is extremely important! The detector placements shown on these drawings have been chosen after a careful evaluation of all facets of the area being protected. Such factors as air currents, temperature, humidity, pressure, and the nature of the load have been carefully considered. Especially noted have been the room or area configuration and the type of ceiling (sloped or flat, smooth or beamed) . Faraday's extensive experience in the design of the system assures the optimum detector placement and is reflected in these drawings. Sound engineering judgment by qualified personnel must prevail. TO AVOID NUISANCE ALARMS: DO NOT locate the 8900 or 8901 detectors where excessive smoke concentrations exist under normal conditions or in areas of prolonged high relative humidity where condensation will occur. DO NOT locate the 8900 or 8901 detectors adjacent to an oil burner, kitchen, or garage where exhaust fumes could trigger an alarm. Other causes of false alarms are dust accumulation, high wind velocity, heavy concentrations of steam, heavy pipe or cigar smoke, and certain aerosol sprays. DO NOT locate the 8902 or 8903 detectors in an area of prolonged high relative humidity when condensation will occur or adjacent to oil burners or in garages, where exhaust fumes could trigger an alarm. Siemens Building Technologies, Inc. 8 Fernwood Road Florham Park, New Jersey 07932 P/N 315-081943FA-15 AIR CURRENTS Before a detector can sense afire, the products of combustion or smoke must travel from the fire to the detector. Since their travel is especially influenced by air currents, the movement of air must be considered in the design of the system. While combustion products tend to rise, drafts from hallways, air diffusers, fans, etc. , may aid or hinder the travel of combustion products to the detector. When positioning a detector at a particular location, consideration must be given to windows and doors, both open and closed, and to influencing air movement. A detector should never be installed in the air stream of a room air supply diffuser. It may be advantageous to position a detector closer to an air return. The distance that products of

FAQs

How should detectors be placed on ceilings or walls?

Place the detector on the ceiling at least 6 inches from a side wall, or on a wall 6 inches from the ceiling. In special cases such as computer room underfloors, the velocity may range between 300 and 1200 ft/min, following the provided guidance.

What wiring guidance applies to listed remote lamps 8922 or 8923?

Wire listed remote lamps 8922 or 8923 at 24V with 5mA mas, using one remote lamp per detector, and observe end-of-line device polarity if applicable.

What conditions should be avoided to prevent nuisance alarms?

Do not locate models 8900/8901 where excessive smoke occurs under normal conditions or where prolonged high humidity causes condensation. Avoid placing them adjacent to oil burners, kitchens, or garages where exhaust fumes could trigger alarms, and similarly avoid models 8902/8903 in comparable high-humidity or exhaust-fume locations.

Oct 29, 2026

Upload by AfterMidnight