Description

The System Sensor 2251TB is a commercial smoke and heat detector designed for compatible addressable fire alarm systems. It combines a smoke sensing chamber with a 135°F (57.2°C) fixed-temperature thermal sensor in a single device, providing dependable fire detection for a wide range of commercial applications.

The detector features rotary decimal addressing, dual status LEDs with 360° visibility, plug-in installation, and continuous communication with the fire alarm control panel for alarm reporting and maintenance supervision. This product is intended exclusively for commercial fire alarm installations.

Product Functions

• Detects airborne smoke
• Provides 135°F (57.2°C) fixed-temperature heat detection
• Reports smoke and heat alarm conditions separately
• Continuous detector supervision
• Individual device identification
• Dual LED status indication
• Magnetic functional testing
• Automatic maintenance monitoring

Electrical & System Information

The 2251TB operates on compatible addressable Signaling Line Circuits (SLC) with an operating voltage range of 15–32 VDC. It uses rotary decimal switches for local addressing and communicates detector status continuously with the fire alarm control panel.

The detector combines a smoke sensing chamber with dual electronic thermistors for fixed-temperature thermal detection, allowing the control panel to distinguish between smoke and heat alarm events.

Features

• Commercial smoke and heat detector
• Smoke sensing chamber
• 135°F (57.2°C) fixed-temperature thermal sensor
• Rotary decimal addressing
• Dual LEDs with 360° visibility
• Plug-in detector head
• Low-profile housing
• Magnetic test capability
• Low standby current
• Superior EMI protection
• Duct application compatible

Mounting & Design

The 2251TB installs on compatible B501, B210LP, B224RB, B224BI, B200S, and B200SR detector bases. Its plug-in design allows quick installation, inspection, testing, cleaning, and replacement without disturbing field wiring.

The detector is suitable for ceiling installations and is also listed for compatible duct smoke detector applications when installed in approved housings.

Protection & Applications

Suitable for:

• Office Buildings
• Schools
• Hospitals
• Hotels
• Retail Facilities
• Warehouses
• Mechanical Rooms
• HVAC Duct Systems
• Commercial Properties

Compatibility

Compatible with:

• System Sensor Addressable Fire Alarm Control Panels
• Compatible SLC Fire Alarm Systems
• B501 Detector Base
• B210LP Detector Base
• B224RB Relay Base
• B224BI Isolator Base
• B200S Sounder Base
• B200SR Sounder Relay Base
• RA400Z Remote LED Annunciator

Always verify compatibility with the installed fire alarm control panel, detector base, SLC protocol, firmware version, and project requirements before installation.

Technical Specifications

Manufacturer: System Sensor

Parent Company: Honeywell

Model: 2251TB

Product Type: Commercial Smoke and Heat Detector

Detection Method: Smoke Sensing Chamber with Fixed-Temperature Thermal Sensor

Fixed Temperature Rating: 135°F (57.2°C)

Operating Voltage: 15–32 VDC

Typical Standby Current: 300 µA @ 24 VDC

Maximum Alarm Current: 6.5 mA @ 24 VDC

Addressing: Rotary Decimal Switches

Status Indicators: Dual LEDs (360° Visibility)

Operating Temperature: 32°F to 100°F (0°C to 38°C)

Operating Humidity: 10%–93% RH Non-Condensing

Diameter: 4.1 in. (104 mm) on B501 Base; 6.1 in. (155 mm) on B210LP Base

Height: 2.0 in. (51 mm)

Weight: 5.2 oz. (147 g)

Mounting: Compatible Detector Base Required

Application: Indoor Commercial Fire Alarm Systems

Listings: UL Listed for compatible fire alarm applications; suitable for compatible duct smoke detector installations. Verify product labeling and project requirements before installation.

Applications

The System Sensor 2251TB is designed for commercial fire alarm systems requiring combined smoke and fixed-temperature heat detection within a single detector. Typical applications include office buildings, schools, healthcare facilities, hotels, retail spaces, warehouses, mechanical areas, HVAC duct systems, and other commercial occupancies utilizing compatible addressable fire alarm control panels.

2251TB Datasheet