Overview
The Gems FS-550 flow switch 29608 is an industrial-grade paddle flow sensor engineered for pilot duty flow monitoring and control. Built with 316 stainless steel construction and rated for high-pressure service up to 2000 psi, this sensor detects flow/no-flow conditions in either direction and is ideal for process automation, safety interlocks, and fluid management systems across manufacturing, HVAC, water treatment, and marine applications.
Key Features
- Adjustable flow range: 15.0–52.0 GPM accommodates varied system requirements
- Paddle sensor design ensures accurate, reliable flow detection in both directions
- High-pressure rating: 2000 psi for demanding industrial duty
- SPDT electrical contact (20 VA pilot duty) rated 50–240 VAC
- Compact, lightweight design (390–325 grams) for easy installation in tight spaces
- Extended temperature range: operates at –30°F and higher
Technical Specifications
- Flow Range: 15.0–52.0 GPM (adjustable)
- Port Size: 1″ NPT Male
- Body Material: 316 Stainless Steel
- Wetted Materials: 316 Stainless Steel, Teflon®, Ceramic
- Switch Type: SPDT (Single Pole Double Throw)
- Pilot Duty Rating: 20 VA
- Voltage Range: 50–240 VAC
- Electrical Termination: 18 AWG, 24″–26″ polymeric leads
- Maximum Pressure: 2000 psi (138 bar)
- Operating Temperature: –30°F to +180°F (typical)
- Set Point Accuracy: ±25%
- Weight: 0.86–0.72 lbs (390–325 grams)
- Dimensions: 2.6 × 2.3 × 10.3 inches
- Country of Origin: USA
- National Stock Number (NSN): 5930-01-372-0967
- Series: FS-550
Typical Applications
- Pilot-duty control circuits for pump start/stop and solenoid valve actuation
- Flow monitoring interlocks for HVAC and chiller systems
- Water treatment, cooling tower, and circulation system protection
- Marine engine and cooling loop flow detection
- Process safety and emergency shutdown systems requiring low-power switching
Compatibility & Replacements
Compatible With
- Pilot-duty control circuits operating at 50–240 VAC
- PLC and automation controller solenoid valve inputs
- Industrial HVAC and process control systems
- Standard 1″ NPT port system installations
- Systems requiring SPDT relay-level switching (20 VA maximum load)
Replaces / Drop-In Replacement For
- Gems FS-550 variants with matching NPT port and flow range
- Legacy Gems Sensors paddle flow switches in the FS-550 series
- OEM installations originally specified Gems 29608
Works With
- Industrial solenoid valves rated for pilot duty control
- PLC analog/digital input modules for flow status monitoring
- Standard industrial 50–240 VAC control systems
- Flow monitoring and safety relay systems
- HVAC, marine, and process automation platforms
