System Sensor 4WTR-B Smoke Detector

The System Sensor 4WTR-B is a commercial 4-wire smoke detector designed for compatible conventional fire alarm systems. As part of the i3 Series, it combines smoke detection with an integrated 135°F (57.2°C) fixed-temperature heat sensor and a built-in Form C alarm relay, providing dependable fire detection and auxiliary control capabilities in a single device.

The detector incorporates automatic drift compensation, dual-color LED status indication, plug-in installation, and installer-friendly features that simplify installation, maintenance, and periodic testing. This product is intended exclusively for commercial fire alarm installations.

Product Functions

• Detects airborne smoke
• Integrated 135°F fixed-temperature heat detection
• Built-in Form C alarm relay
• Automatic drift compensation
• Continuous smoke monitoring
• Dual-color LED status indication
• Magnetic functional testing
• Supports remote maintenance signaling

Electrical & System Information

The 4WTR-B operates on compatible 12/24 VDC non-polarized 4-wire conventional fire alarm circuits with an operating voltage range of 10–35 VDC. Automatic drift compensation and smoothing algorithms continuously adjust detector sensitivity to maintain dependable performance throughout its service life.

The integrated Form C relay provides auxiliary control for compatible fire alarm applications, while the detector supports remote maintenance and synchronization accessories when used with approved system components.

Features

• Commercial 4-wire smoke detector
• Integrated 135°F thermal sensor
• Built-in Form C relay
• Automatic drift compensation
• Dual-color LED indicators
• Plug-in detector head
• Low-profile housing
• Magnetic test capability
• Removable insect screen
• Stop-Drop ‘N Lock™ installation
• Remote maintenance signaling
• Flexible mounting options

Mounting & Design

The 4WTR-B includes an integrated mounting base compatible with 3½-inch and 4-inch octagonal boxes, single-gang boxes, and 4-inch square electrical boxes with plaster rings. It may also be mounted directly to the ceiling using approved drywall anchors where permitted.

Its plug-in detector head allows quick removal for inspection, cleaning, testing, or replacement without disturbing field wiring.

Protection & Applications

Suitable for:

• Office Buildings
• Schools
• Hospitals
• Hotels
• Retail Facilities
• Warehouses
• Government Buildings
• Industrial Facilities
• Commercial Properties

Compatibility

Compatible with:

• Conventional Fire Alarm Control Panels
• 4-Wire Initiating Device Circuits
• RRS-MOD Reversing Relay/Sync Module
• 2W-MOD2 Maintenance Module
• Compatible Auxiliary Relay Applications
• Standard Electrical Back Boxes

Always verify compatibility with the installed fire alarm control panel, power supply, relay application, and project requirements before installation.

Technical Specifications

Manufacturer: System Sensor

Parent Company: Honeywell

Model: 4WTR-B

Series: i3 Series

Product Type: Commercial 4-Wire Smoke Detector

Detection Method: Photoelectric Smoke Sensing with Fixed-Temperature Heat Detection

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

Relay Type: Form C Alarm Relay

Circuit Type: 4-Wire Conventional

Operating Voltage: 10–35 VDC (12/24 VDC Nominal)

Maximum Ripple Voltage: 30%

Average Standby Current: 50 µA

Maximum Alarm Current: 35 mA

Alarm Contact Rating: 0.5 A @ 30 VAC/DC

Form C Relay Rating: 2 A @ 30 VAC/DC

Smoke Sensitivity: 2.5% Obscuration per Foot (Nominal)

Status Indicators: Dual-Color LEDs

Operating Temperature: 32°F to 100°F (0°C to 37.8°C)

Operating Humidity: 0%–95% RH Non-Condensing

Dimensions: 5.3 in. Diameter × 2.0 in. Height

Mounting: Integrated Plug-In Base

Application: Indoor Commercial Fire Alarm Systems

Listings: UL 268, FM Approved, CSFM, and additional regional approvals where applicable. Verify product labeling for the intended installation.

Applications

The System Sensor 4WTR-B is designed for commercial fire alarm systems requiring dependable smoke detection with integrated thermal sensing and auxiliary relay functionality. Typical applications include offices, schools, hospitals, hotels, retail facilities, warehouses, industrial buildings, government facilities, and other commercial occupancies utilizing compatible conventional 4-wire fire alarm systems.

4WTR-B Datasheet