Honeywell FSL100-SM21 Swivel Mount

The Honeywell FSL100-SM21 is an optional two-axis swivel mounting bracket designed for Honeywell FSL100 Series flame detectors. It allows installers to mount and accurately aim compatible flame detectors toward a protected hazard area while also increasing detector stand-off from the mounting surface where additional clearance, cooling, or ventilation is beneficial. Honeywell identifies the FSL100-SM21 specifically as the optional swivel mount for the FSL100 flame detector family.

The mount can be attached to a wall, ceiling, or suitable pole and uses two adjustable pivot points to position the detector’s field of view. Honeywell also states that the FSL100-SM21 is suitable for hazardous-area applications when installed and maintained according to the applicable safety requirements.

Product Functions

• Mounts compatible Honeywell FSL100 flame detectors
• Provides two-axis detector adjustment
• Allows precise alignment of the detector field of view
• Supports wall mounting
• Supports ceiling mounting
• Supports suitable pole mounting
• Increases detector stand-off from the mounting surface
• Can improve clearance for cooling and ventilation
• Suitable for compatible hazardous-area applications
• Uses a dedicated detector attachment plate
• Uses a separate wall mounting plate
• Supports secure mechanical attachment with stainless-steel hardware
• Designed specifically for the FSL100 flame detector family
• Requires no electrical power
• Contains no sensing or alarm electronics

Two-Axis Swivel Adjustment

The primary feature of the FSL100-SM21 is its two-axis swivel mechanism.

The adjustable joints allow a compatible flame detector to be aimed accurately toward the area of fire risk after the wall plate has been secured. This is important for optical flame detectors because reliable coverage depends heavily on maintaining an unobstructed line of sight and correctly positioning the detector’s cone of vision.

The two pivot points allow the installer to make both horizontal and vertical adjustments before tightening the swivel bolts into their final position.

FSL100 Detector Compatibility

The FSL100-SM21 is designed for the Honeywell FSL100 Series flame detector family, which includes:

• FSL100-IR3
• FSL100-IR3-W
• FSL100-UV
• FSL100-UVIR
• Other documented FSL100 detector variants

Honeywell’s technical handbook specifically includes the FSL100-SM21 as the optional mounting accessory for FSL100 flame detectors.

Compatibility should still be checked against the exact detector model and its certification requirements, particularly for hazardous locations.

Wall, Ceiling & Pole Mounting

The FSL100-SM21 provides flexible mounting for different installation environments.

Honeywell instructs installers to secure the wall plate to a vibration-free wall, ceiling, or pole using four suitable fixings. The mounting hardware used to secure the plate to the building structure is not supplied with the swivel mount.

Typical mounting applications include:

• Structural walls
• Building columns
• Ceilings
• Equipment frames
• Process-area supports
• Suitable mounting poles

The supporting surface should be rigid enough to prevent movement that could alter the flame detector’s field of view.

Detector Aiming

The FSL100 flame detector family has a documented 90° cone of vision, making accurate detector aiming an important part of system design.

The SM21 swivel allows the installer to aim the detector toward the hazard after the mounting plate has been secured.

Typical factors that should be considered when aiming the detector include:

• Expected fire location
• Detector range
• Obstructions
• Equipment geometry
• Shadowing
• Mounting height
• Field-of-view overlap
• Potential smoke accumulation
• Required detector coverage

Honeywell recommends overlapping detector coverage where necessary so that obstructions do not create unmonitored shadow areas.

Increased Detector Stand-Off

The FSL100-SM21 can also be used to increase the distance between the detector and its mounting surface.

Honeywell specifically notes that this additional stand-off can help with cooling and ventilation around the detector.

This may be useful in applications where a detector mounted directly against a surface would receive less airflow or where additional positioning clearance is needed.

Hazardous-Area Applications

Honeywell states that the FSL100-SM21 is suitable for hazardous-area applications, subject to the applicable installation and safety requirements.

The technical handbook warns that rubbing the GRP detector housing or mounting can generate static electricity capable of creating an explosion hazard in combustible atmospheres.

For this reason, Honeywell instructs users to clean the mount and detector using only a clean damp cloth in hazardous locations.

Construction

Honeywell lists the swivel mount construction as:

Swivel Material: PA66, UV resistant
Fixings: 316 stainless steel

This material combination provides a lightweight mounting assembly with corrosion-resistant metal fasteners suitable for demanding industrial and outdoor-style flame detection installations when used within the detector system’s approved environmental limits.

Weight

Honeywell publishes the following FSL100 detector weight information:

Detector Only: Approximately 465 g / 1.05 lb
Detector with Optional Swivel Mount: Approximately 745 g / 1.67 lb

This indicates that the SM21 adds approximately 280 g / 0.62 lb to the detector installation.

The mounting surface and fasteners should be capable of securely supporting the complete detector and bracket assembly.

Installation Information

Typical FSL100-SM21 installation includes:

• Loosening one of the swivel joints to simplify detector attachment
• Securing the wall plate to a vibration-free wall, ceiling, or pole
• Opening the compatible FSL100 detector enclosure
• Removing the four detector attachment bolts
• Using those bolts to secure the detector body to the swivel mounting plate
• Positioning the swivel hub closest to the detector cable gland
• Ensuring the cable gland points downward in the final installation
• Reassembling the detector
• Connecting the detector power and signal wiring
• Adjusting the detector to the required viewing angle
• Fully tightening both swivel joints
• Verifying all mounting hardware is secure
• Testing the detector with a Honeywell-approved test lamp

Honeywell specifies a tightening torque of 2 Nm / 1.5 ft-lb for the four detector cover screws during reassembly.

Cable Gland Orientation

Honeywell specifically requires the detector cable gland to point downward when the detector and SM21 mounting assembly are fully installed.

Correct cable-gland orientation is important for proper environmental protection and installation integrity.

The swivel hub should therefore be oriented near the gland when the detector is attached to the mounting plate.

Testing & Maintenance

Testing and inspection should confirm:

• Secure wall or pole mounting
• Secure detector attachment
• Correct detector viewing direction
• Fully tightened swivel bolts
• Proper cable gland orientation
• Unobstructed detector window
• Correct detector field of view
• No mechanical damage
• No corrosion or damaged hardware
• Proper detector response during functional testing
• Correct operation with a Honeywell-approved test lamp

Honeywell recommends periodically cleaning contamination from the mount and detector using a lightly dampened microfiber cloth. Dry cloths or paper should not be used in flammable atmospheres because of the potential for static discharge.

Product Identification

• Manufacturer: Honeywell
• Model: FSL100-SM21
• Product Type: Flame Detector Swivel Mount
• Primary Function: Adjustable FSL100 Detector Mounting
• Compatible Family: FSL100 Flame Detectors
• Adjustment: Two Axis
• Mounting: Wall / Ceiling / Pole
• Swivel Material: UV-Resistant PA66
• Fastener Material: 316 Stainless Steel
• Electrical Components: None
• Operating Power: None
• Hazardous-Area Application: Supported where applicable
• Detector Weight with Mount: Approximately 745 g / 1.67 lb
• Detector Stand-Off: Increased compared with direct mounting
• Installation Hardware to Structure: Not included
• Application: Flame Detector Positioning and Alignment

Protection & Applications

Suitable for:

• Honeywell FSL100 Flame Detection Systems
• IR3 Flame Detectors
• UV Flame Detectors
• UV/IR Flame Detectors
• Industrial Fire Detection
• Hazardous-Area Flame Detection
• Process Plants
• Manufacturing Facilities
• Fuel Storage Areas
• Engine Rooms
• Machinery Areas
• Warehouses
• Chemical Processing Facilities
• Oil and Gas Applications
• Power Generation Facilities
• Wall-Mounted Flame Detection
• Ceiling-Mounted Flame Detection
• Pole-Mounted Flame Detection

The Honeywell FSL100-SM21 Swivel Mount is particularly useful where a compatible FSL100 flame detector must be precisely aimed toward a specific fire hazard rather than mounted flat against a surface. Its two-axis adjustment, stainless-steel hardware, hazardous-area suitability, and ability to increase detector stand-off make it a practical positioning accessory for FSL100 flame detection systems.