Pyxis ST-765P-DCL Free Chlorine + Sulfite + pH Sensor (CPVC)
CPVC dechlorination sensor measuring Free Chlorine (0.00-5.00ppm) and Sulfite (0.0-100.0ppm) simultaneously, plus pH and temperature. Replaceable front-loading reference electrode, Bluetooth-ready with MA-CR adapter.
Pyxis ST-765P-DCL Free Chlorine + Sulfite + pH Sensor (CPVC)
The ST-765P-DCL is a CPVC-bodied, membrane-less sensor that measures Free Chlorine and Sulfite alongside pH and temperature in a single probe, using Pyxis Lab's bare-gold electrochemical detection technology. This DCL variant tracks residual oxidizer and neutraliser dosing together in one pass, suited to dechlorination monitoring. Internal pH compensation up to pH 9.0 keeps oxidizer readings consistent with DPD wet chemistry and compliant with USEPA-334.0 and ISO-7393 methodology. The replaceable, front-loading reference electrode avoids the membrane and gel replacement of older amperometric designs, giving a typical service life of up to 2 years.
Description
The ST-765P-DCL is a CPVC-bodied, membrane-less sensor that measures Free Chlorine and Sulfite simultaneously alongside pH and temperature in a single probe, using Pyxis Lab’s bare-gold electrochemical detection technology. This dual-parameter capability makes it particularly suited to dechlorination monitoring, where residual oxidizer and neutralizer dosing both need to be tracked in one pass rather than with separate instruments.
Internal pH compensation up to pH 9.0 keeps oxidizer readings consistent with DPD wet chemistry and compliant with USEPA-334.0 and ISO-7393 methodology. The reference electrode assembly is replaceable and front-loading, avoiding the membrane and gel replacement associated with older amperometric designs, and giving a typical electrode service life of up to 2 years with reduced startup polarization time.
Dual isolated 4-20mA outputs plus RS-485 Modbus support integration with a PLC, SCADA, or third-party controller, and the optional MA-CR Bluetooth Adapter adds wireless calibration and diagnostics via the uPyxis mobile app. The CPVC body suits clean water applications: potable water, secondary water supply, domestic water, and decorative water features.
Why Use This
DPD-Consistent Accuracy
Internal pH and temperature compensation up to pH 9.0 keeps Free Chlorine and Sulfite readings aligned with DPD wet chemistry and USEPA-334.0 / ISO-7393 methodology.
Lower Maintenance
The replaceable, front-loading reference electrode avoids membrane and gel replacement, with a typical service life of up to 2 years and reduced startup polarization time.
Flexible Integration
Dual isolated 4-20mA outputs and RS-485 Modbus connect to a PLC, SCADA, or third-party controller, with optional Bluetooth calibration via the MA-CR adapter.
Applications
- Dechlorination monitoring — tracks residual chlorine and sulfite neutralizer dosing together in one pass
- Potable water treatment — combined chlorine, sulfite, and pH monitoring for clean water systems
- Secondary and domestic water supply monitoring — CPVC body suited to non-industrial clean water applications
- PLC/SCADA dosing integration — dual 4-20mA and RS-485 outputs support automated dechlorination control
FAQ
What makes the DCL variant different from other ST-765P sensors?
It measures Free Chlorine (0.00-5.00ppm) and Sulfite (0.0-100.0ppm) simultaneously in one probe, making it suited to dechlorination monitoring where both residual oxidizer and neutralizer dosing need tracking together.
How accurate are the oxidizer readings?
Oxidizer precision is ±0.01mg/L or 1% of value, with pH compensation up to 9.0 to keep readings consistent with DPD wet chemistry.
How long does the electrode last before replacement?
The replaceable, front-loading reference electrode has a typical service life of up to 2 years.
What water types is this sensor designed for?
The CPVC body suits clean water applications: potable water, secondary water supply, domestic water, and decorative water features.
Resources
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