Pool Link Legacy Probe Chamber w/ Piston Flow Switch

The Pool Link Legacy Probe Chamber w/ Piston Flow Switch is a commercial bypass flow cell manifold engineered for legacy Pool Link automation systems and multi-parameter aquatic chemical controllers. Plumbed into an auxiliary bypass line across the main pool recirculation loop, it provides a stable, non-turbulent sampling stream for analytical electrodes. Instead of a spinning rotary paddle wheel, this variation incorporates a vertical or horizontal magnetic displacement piston (shuttle) assembly, providing robust mechanical interlock actuation that resists fouling from suspended solids, hair, and calcification in high-load commercial pools.

System Overview & Hardware Architecture

Engineered for continuous chemical monitoring and fail-safe operation in heavy-duty commercial natatoriums and aquatic facilities:

• Monolithic Machined Acrylic Block: Precision-bored from clear, chemical-resistant cast acrylic. The transparent housing allows operators to inspect probe cleanliness, identify trapped air bubbles, and verify internal piston movement without opening the pressurized sampling line.

• Positive-Displacement Magnetic Piston Assembly: Uses an internal weighted or spring-biased magnetic shuttle/piston that lifts or shifts when incoming water velocity reaches operating threshold. The embedded magnet triggers an external or encapsulated hermetically sealed reed switch to close the low-voltage safety interlock circuit.

• Fouling-Resistant Operation: The linear piston mechanism has no rotating axles or paddle blades, significantly reducing the likelihood of mechanical seizure caused by calcium scaling, hair, lint, or particulate accumulation common in high-load public pools.

• Inlet Metering Needle Valve: Chemical-resistant, fine-threaded needle valve located at the sample inlet to regulate bypass velocity and eliminate high-velocity impingement against delicate glass pH and platinum ORP sensing tips.

• Water Sample Draw Petcock: Integrated low-pressure sampling valve positioned adjacent to the probe measurement chamber, allowing operators to draw representative pool water for manual photometer, DPD colorimeter, or titrimetric calibration tests.

Technical Specifications

• Sensor Port Layout:

  • Two to three threaded or compression gland ports (standard 1/2" NPT or 3/4" NPT) accommodating combination glass-body pH probes, platinum-band ORP sensors, and temperature probes.

  • Captive compression collars and chemical-resistant EPDM/Viton O-rings to maintain hydraulic seals under pressure.

• Electrical Safety Interlock:

  • Hermetically sealed magnetic reed switch actuated by the internal piston magnet.

  • Form A dry-contact configuration rated up to 24V AC/DC, 0.5A maximum current.

  • Direct two-wire terminal or jacketed pigtail lead connecting to the controller's safety interlock loop.

• Hydraulic Operating Limits:

  • Actuation Flow Rate: Typically closes contact at 0.3 to 0.7 GPM (approx. 1.1 to 2.6 LPM) minimum flow velocity.

  • Maximum Working Pressure: 50 PSI (approx. 3.45 bar).

  • Operating Water Temperature: 32°F to 120°F (0°C to 49°C).

• Plumbing Connections: Standard 1/4" NPT female ports equipped with 3/8" OD compression tube adapters for semi-rigid polyethylene sample tubing.