Commercial Pool and Spa Supplies
Pool Link 500 Series, FAC Probe Gel
Pool Link 500 Series, FAC Probe Gel
SKU:LINK-FACGEL
Couldn't load pickup availability
The Pool Link 500 Series FAC Probe Gel (Pool Link / Link Automation) is a specialized, pre-buffered electrochemical electrolyte gel formulated specifically for the internal reservoir of the Pool Link 500 Series Amperometric Free Available Chlorine (FAC) 0–20 PPM probe.
Held in place behind the probe's microporous membrane cap, the electrolyte provides an ion-conductive pathway between the internal silver/silver chloride ($\text{Ag/AgCl}$) reference anode and the noble metal (gold or platinum) working cathode. It maintains a constant internal chemical environment to facilitate the electrochemical reduction of hypochlorous acid ($\text{HOCl}$) into chloride ions, producing the measurable micro-current proportional to chlorine concentration.
Chemical Formulation & Functional Characteristics
Engineered to maintain stable baseline polarization and linear current response in continuous commercial aquatic operation:
-
High-Purity Buffered Matrix: Formulated with a stabilized potassium chloride ($KCl$) or sodium chloride base buffered to a precise internal pH to maintain steady ionic strength and reference potential.
-
Gelled High-Viscosity Rheology: Formulated with high-grade, non-reactive cellulosic or synthetic polymer thickening agents. The gelled consistency prevents rapid electrolyte weeping or boundary layer drying behind the microporous membrane under line pressure variations (up to 50 PSI).
-
Anti-Evaporative & Thermal Stabilizers: Contains conditioning agents to maintain electrolyte fluidity and prevent crystal dropout or desiccation across standard operating pool temperatures (35°F to 120°F / 2°C to 49°C).
-
Air-Release Optimization: Formulated with surface tension characteristics that allow trapped micro-air bubbles to rise and escape easily during cap filling, preventing bubble entrapment against the cathode face.
Technical Specifications
-
Compatible Sensor: Pool Link 500 Series Amperometric Free Available Chlorine (FAC) Probe (0–20 PPM).
-
Electrochemical Compatibility: Formulated specifically for $\text{Au-Ag/AgCl}$ or $\text{Pt-Ag/AgCl}$ amperometric cell pairs.
-
pH Buffering Range: Stabilized neutral/mildly acidic internal buffer system to optimize the reduction potential of diffused $\text{HOCl}$.
-
Operating Temperature Limits: 35°F to 120°F (2°C to 49°C).
-
Shelf Life: 2 years when stored sealed in original dropper bottles at room temperature (50°F to 80°F / 10°C to 27°C) protected from direct sunlight.
-
Standard Container Volume: Typically supplied in 30 mL to 60 mL (approx. 1 to 2 fl. oz.) squeeze dropper bottles fitted with a precision needle-tip nozzle for clean membrane filling.
-
Refill Yield: One 30 mL bottle delivers approximately 10 to 15 complete membrane cap recharges (typical fill volume is 1.5 mL to 2.5 mL per service).
Cap Refilling & Re-Commissioning Procedure
Close the inlet and outlet isolation valves on the 500 Series acrylic flow cell to relieve hydraulic pressure. Unthread the probe's compression collar and extract the sensor body from the manifold.
Verification: Flow cell pressure gauge drops to 0 PSI and no bypass water flows from the open port.
Unscrew the lower membrane cap and discard old electrolyte into a sink or waste container. Rinse the internal cathode tip and cap reservoir thoroughly with distilled or deionized water, then gently blot dry with a lint-free tissue.
Verification: The internal chamber is clean and the cathode surface is free of mineral buildup or discolored gel residue.
Invert the FAC Probe Gel bottle and tap it gently to dislodge air bubbles from the dispensing nozzle. Carefully fill the membrane cap approximately 3/4 full with fresh gel, avoiding micro-bubble entrapment.
Verification: The gel inside the cap is clear, continuous, and free of visible air pockets.
Holding the probe vertically, slowly screw the filled membrane cap onto the probe shaft. Allow excess gel to escape through the pressure-relief threads/vent without forcing or stretching the delicate membrane face.
Verification: The cap is firmly seated against its stop and the outer membrane remains smooth and flat.
Reinstall the probe in the acrylic flow cell, tighten the compression collar, and reopen the bypass valves. Restore steady water flow (0.5 to 1.5 GPM) and let the sensor polarize under power for 1 to 2 hours before running span calibration.
Verification: The FAC reading on the Pool Link 501 controller settles into a stable, non-drifting baseline matching a DPD photometer test.
