System Sensor B200SR-LF-WH Low Frequency Sounder Base

The System Sensor B200SR-LF-WH Low Frequency Sounder Base is an intelligent detector sounder base designed to produce a 520 Hz low-frequency audible alarm signal for fire alarm applications, particularly sleeping areas where low-frequency notification is required. The base is designed for use with compatible System Sensor 200-Series intelligent detector heads and combines detector mounting with local audible notification.

The B200SR-LF-WH is the bright white version of the B200SR-LF series. It produces a fundamental frequency of approximately 520 Hz ±10% using a square wave or equivalent waveform and is designed to comply with low-frequency sleeping-space notification requirements.

Product Functions

• Provides 520 Hz low-frequency audible fire alarm notification
• Designed for sleeping-area notification applications
• Functions as a mounting base for compatible intelligent detectors
• Supports compatible System Sensor 200-Series sensor heads
• Produces greater than 85 dBA at 10 feet under specified conditions
• Supports ANSI Temporal 3 fire alarm signaling
• Supports continuous-tone operation
• Uses an onboard jumper for tone selection
• Requires external 24 VDC nominal sounder power
• Communicates through the detector’s SLC connection
• Supports System Sensor synchronization
• Allows compatible sounder bases to be grouped
• Supports up to six grouped B200SR-LF sounder bases in the documented configuration
• Compatible with existing B501BH-Series sounder-base installations
• Uses a prewired mounting plate
• Provides a mechanical detector locking feature
• Accepts wiring up to 12 AWG
• Bright white housing for finished interior installations
• Designed to meet UL 268 and UL 464 requirements

Low-Frequency Sounder Operation

The primary function of the B200SR-LF-WH is to generate a low-frequency audible alarm signal at approximately 520 Hz.

System Sensor specifies a fundamental frequency of 520 Hz ±10% with a square wave or equivalent waveform. Low-frequency audible notification around 520 Hz is intended to improve awakening effectiveness for sleeping occupants, including individuals with mild to severe hearing loss.

This makes the B200SR-LF-WH particularly suitable for fire alarm systems serving hotels, apartments, dormitories, assisted-living facilities, and other occupancies containing sleeping areas.

Tone Selection

The B200SR-LF-WH supports two primary audible patterns:

• ANSI Temporal 3
• Continuous Tone

Tone selection is accomplished using an onboard jumper. The factory configuration supports the selectable operating arrangement described in the manufacturer’s installation documentation.

ANSI Temporal 3 provides the standardized three-pulse evacuation pattern commonly used for fire alarm signaling, while continuous operation provides an uninterrupted low-frequency audible signal.

Sound Output

The B200SR-LF-WH provides a high-output audible signal while maintaining the low-frequency characteristics required for its intended application.

Sound Output: Greater than 85 dBA minimum at 10 feet
Test Condition: 24 VDC, continuous tone, measured in a UL reverberant room
Fundamental Frequency: Approximately 520 Hz ±10%

Actual sound pressure within an installed building can vary based on room construction, furnishings, doors, mounting location, ambient noise, and other environmental factors.

Sounder Grouping

The B200SR-LF-WH can be incorporated into grouped sounder-base arrangements.

System Sensor’s installation documentation shows an approved configuration allowing up to six B200SR-LF-WH or B200SR-LF-IV sounder bases to be grouped. An intelligent relay module can be used within the documented configuration to activate the group of sounder bases.

This capability can provide coordinated audible signaling across multiple detector locations while retaining intelligent detector supervision through the fire alarm system.

The exact grouping method depends on the fire alarm control panel, programming, power supply, and approved wiring arrangement.

External Power Operation

The B200SR-LF-WH requires an external power source for operation of its integral sounder.

Published external supply ratings include:

External Supply Voltage: 16–33 VDC / VFWR
Standby Current: 1 mA maximum
Alarm Current at 33 VDC: 65 mA maximum
Alarm Current at 24 VDC: 90 mA maximum
Alarm Current at 16 VDC: 125 mA maximum

The external power supply must be compatible with the sounder-base installation and sized according to the number of connected bases, system configuration, and applicable current requirements.

SLC Operation

The detector installed in the B200SR-LF-WH communicates with the compatible fire alarm control panel through the Signaling Line Circuit.

SLC Operating Voltage: 15–32 VDC
SLC Standby Current: Determined by the installed compatible sensor

The sounder power and SLC communication circuits are separate. System Sensor recommends appropriate wiring practices to protect the communication loop from electrical interference.

Reverse Compatibility

The B200SR-LF series is designed to maintain compatibility with existing B501BH-Series sounder base installations, providing an upgrade path for supported systems.

This compatibility can make the B200SR-LF-WH useful for retrofit projects where older compatible sounder-base installations are being upgraded to provide 520 Hz low-frequency notification.

Compatibility should still be confirmed against the specific detector, fire alarm control panel, existing wiring, and manufacturer documentation before replacement.

Electrical Specifications

The B200SR-LF-WH electrical specifications include:

External Supply Voltage: 16–33 VDC / VFWR
External Supply Standby Current: 1 mA maximum
Alarm Current @ 33 VDC: 65 mA maximum
Alarm Current @ 24 VDC: 90 mA maximum
Alarm Current @ 16 VDC: 125 mA maximum
SLC Operating Voltage: 15–32 VDC
SLC Standby Current: Dependent on installed sensor
Sound Output: Greater than 85 dBA minimum at 10 feet at 24 VDC in continuous tone
Fundamental Frequency: 520 Hz ±10%
Tone Options: ANSI Temporal 3 / Continuous
Relative Humidity: 10%–93%, non-condensing

Physical Dimensions

The B200SR-LF-WH uses a large-format sounder-base housing designed to accommodate a compatible intelligent detector.

Base Diameter: 6.875 in / 17.46 cm
Base Height Without Sensor: 2.0 in / 5.08 cm
Weight: 0.6 lb / 272 g
Housing Color: Bright White

The operating temperature range is determined in conjunction with the installed compatible sensor and should be verified using the applicable System Sensor base/sensor cross-reference information.

Installation Information

The B200SR-LF-WH incorporates a prewired mounting plate designed to simplify installation and accommodate multiple junction-box configurations. The sounder-base housing locks to the mounting plate using retaining screws.

Typical field installation includes:

• SLC communication wiring
• External sounder power wiring
• Correct circuit polarity
• Compatible intelligent detector installation
• Selection of Temporal 3 or continuous tone
• Proper sounder-base grouping where applicable
• Compatible control panel programming
• Verification of required synchronization
• Secure attachment of the base to the mounting plate
• Proper installation of the detector head

The base supports wire sizes up to 12 AWG. System Sensor specifies that the power and communication conductors should use appropriate wiring methods to minimize electrical interference.

Mechanical Locking Feature

The B200SR-LF-WH incorporates a mechanical locking feature designed to restrict unauthorized removal of the attached detector head.

This feature can be useful in public, residential, institutional, and other installations where detector tampering is a concern. The locking mechanism should be enabled and serviced according to System Sensor installation instructions.

Testing & Maintenance

Testing should confirm:

• Proper communication between the installed detector and fire alarm control panel
• Correct detector operation
• Proper low-frequency sounder activation
• Correct 520 Hz audible output
• Adequate external sounder power
• Correct SLC voltage and communication
• Proper grouped sounder activation where configured
• Correct synchronization where applicable
• Secure detector-to-base connection
• Secure mounting plate and retaining screws
• Proper field wiring and terminal connections

System Sensor specifies that the detector used with the base must be tested and maintained regularly in accordance with applicable NFPA 72 requirements. The manufacturer’s installation documentation also states that the detector should be cleaned at least annually.

Product Identification

Manufacturer: System Sensor / Honeywell
Model: B200SR-LF-WH
Product Type: Low Frequency Sounder Base
Primary Function: Detector Base with Low-Frequency Audible Notification
Color: Bright White
Fundamental Frequency: 520 Hz ±10%
Tone Options: ANSI Temporal 3 / Continuous
Sound Output: Greater than 85 dBA at 10 ft under specified conditions
External Supply Voltage: 16–33 VDC / VFWR
External Standby Current: 1 mA maximum
Alarm Current @ 24 VDC: 90 mA maximum
SLC Operating Voltage: 15–32 VDC
Diameter: 6.875 in / 17.46 cm
Height: 2.0 in / 5.08 cm without sensor
Weight: 0.6 lb / 272 g
Relative Humidity: 10%–93%, non-condensing
Compatibility: Supported System Sensor intelligent detector heads
Legacy Installation Compatibility: B501BH-Series sounder base installations
Application: Low-Frequency Fire Alarm Notification / Sleeping Areas

Protection & Applications

Suitable applications include:

• Commercial Fire Alarm Systems
• Intelligent Addressable Fire Alarm Systems
• Low-Frequency Fire Alarm Notification
• 520 Hz Audible Notification
• Sleeping-Area Notification
• Detector Sounder Applications
• Group Sounder Activation
• Fire Alarm System Retrofits
• Hotels
• Motels
• Apartment Buildings
• Residential Buildings
• College Dormitories
• Assisted-Living Facilities
• Healthcare Facilities
• Hospitals
• Institutional Facilities
• Schools and Universities
• High-Rise Residential Buildings
• Mixed-Use Buildings
• Commercial Life Safety Systems