McDonnell & Miller 114550 FS4-3D 1" Flow Switch with Dual SPDT Switches
McDonnell & Miller 114550 FS4-3D 1" Flow Switch with Dual SPDT Switches
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Apply for Trade Account & Terms →| Performance Parameter | Engineering Baseline Value |
|---|---|
| Manufacturer Part Number (MPN) | 114550 |
| Model Designation | FS4-3D |
| Connection Size | 1 inch NPT |
| Switch Type | Dual SPDT |
Protect your hydronic equipment from flow-related damage using the McDonnell & Miller 114550 FS4-3D 1-inch flow switch. This versatile safety device provides reliable monitoring for liquid lines in commercial and industrial HVAC applications, utilizing the FS4-3D model to actuate electrical circuits when flow reaches or drops below a specific set point.
The unit functions through a precision-engineered paddle mechanism that extends into the pipe. When liquid flows through the line, the force against the paddle moves an internal linkage that triggers the two integrated Single Pole Double Throw (SPDT) switches. This dual-switch design allows for simultaneous signaling of two separate devices, such as a burner cutoff and an alarm system, ensuring comprehensive system oversight.
Key System Performance Baselines:
- Dual switching capability: Includes two independent SPDT switches for versatile circuit control.
- Rugged flow sensing: Features a sensitive, heavy-duty paddle designed for consistent reaction to flow velocity.
- Versatile mounting: Engineered for easy installation into standard 1-inch NPT pipe configurations.
- System protection: Provides a vital safety interlock to prevent equipment operation during low-flow conditions.
⚠️ Application Profile: Ideal for monitoring flow in chilled water systems, hot water boilers, and industrial process piping where equipment protection against dry-fire or low-flow conditions is critical.
