Model 2151 (photoelectric sensor) and model 2151T (photoelectric sensor with thermal) can be used with a variety of adapter bases in several wiring configurations and voltages. Other features include: low current draw, stable performance in high air velocities, built-in tamper resistant base design, remote LED option, removable cover and built-in test switch. The 100 series is designed to meet the performance criteria designated by UL. The sensing chamber is sealed against back pressure air flow. The chamber top is covered by a one piece molded screen which minimizes the entry of dirt and insects. This screen can be removed for cleaning. Additional key features include a variety of mounting bases and a full line of accessories. All 100 Series photoelectric smoke detectors contain a unique optical sensing chamber designed to sense smoke particles produced by a wide range of combustion sources. A custom integrated circuit incorporates signal processing to reduce false alarms.

• Sleek, low-profile design • Compatible with 400 Series product • Two LEDs blink in standby, providing 360° visibility • Broad range of adapter bases available with built-in shorting spring • Hand-held sensitivity reader available

Operating Voltage/Alarm Current	See Adapter Base Selection Guide following
Standby Current	120μA Standby (when mounted in a B110LP base)
Sensitivity	1 – 3.18%/ft.
Height	2.0˝ in B401
Diameter	4.1˝ installed in B401; 6.2˝ installed in B110LP
Shipping Weight	5.2 oz
Construction	Flame retardant thermoplastic
Temperature	Photo: 32°F to 120°F (0° to 49°C); Photo/thermal: 32°F to 100°F (0° to 38°C)
UL Listed Velocity Range	Photo: 0 – 3000 fpm (0 – 15.2 m/s)
Humidity Range	10% – 93% RH non-condensing
Smoke Detector Spacing	On smooth ceilings (as defined in NFPA 72), spacing of 30 feet (900 sq. ft.) may be used as a guide. Other spacing may be used depending on ceiling height, high air movements, and other conditions or response requirements.