Online Residual Chlorine Analyzer
Continuous free chlorine monitoring for drinking water networks, industrial cooling, and chlorine dosing control loops.
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Precision Instrumentation
Featured High-Precision Residual Chlorine & Water Quality Sensors
Direct factory wholesale configurations manufactured under ISO 9001 quality systems with strict 48-hour continuous drift and stability calibration runs.
MPG-6099Plus Multi-Parameter Panel
Consolidated flow-cell station combining residual chlorine, pH, turbidity, conductivity, and dissolved oxygen.
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pH5806 High Temperature pH Sensor
Awarded Shanghai Brand certification; engineered for high-temperature biopharma fermentation and SIP cycles.
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IOT-485-pH Digital Online Sensor
Direct RS485 Modbus RTU communication designed for edge gateways and DCS integration without secondary transmitters.
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0-130℃ High-Temp pH Sensor
Integrated temperature compensation electrode, fully resilient against repetitive steam sterilization up to 130°C.
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Pharma Fermentation pH Probe
Optimized reference electrolyte matrix preventing poisonous fouling in thick microbiological broths and reactors.
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ZDYG-2088-01QX Turbidity Sensor
Infrared 860nm scattered light sensor complete with ultrasonic self-cleaning options for water distribution networks.
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DCA130 Online pH & EC Controller
Dual-channel transmitter managing real-time chlorine disinfection dosing synergy alongside pH and conductivity.
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Technical Roadmap & Analytical Principles
Electrochemical vs. Photometric Residual Chlorine Sensing
Understanding the core physics and electrochemistry of Hypochlorous Acid (HOCl) and Hypochlorite Ion (OCl⁻) detection is critical for wholesale buyers and plant instrument engineers.
Polarographic Membrane Systems
Utilizes a selective microporous gas-permeable PTFE membrane isolating a gold working cathode and silver anode in an internal electrolyte. Hypochlorous acid diffuses across the boundary layer, producing a direct reduction current:
HOCl + 2e⁻ + H⁺ → Cl⁻ + H₂O.
Offers high specificity in industrial wash lines where ionic surfactants would foul open electrodes.
Bare-Electrode Constant Voltage
Employs a 3-electrode potentiostatic system (Working, Counter, Reference) without disposable membranes or consumable chemicals. Integrated auto-cleaning impellers or hydrodynamic sand scrubbing prevent biological film accumulation on the platinum surfaces, drastically reducing OpEx in municipal tap water grids.
DPD Colorimetric Methodology
Follows Standard Methods 4500-Cl G using N,N-diethyl-p-phenylenediamine reagent buffers. Periodic photometric light absorption measurement (510–550 nm) delivers calibration-free reliability for regulatory reporting compliance, irrespective of water conductivity swings or fluctuating pH conditions up to pH 8.5.
| Technology Class | pH Dependency & Compensation | Maintenance Interval | Interference Profile | Optimal Deployment Arena |
|---|---|---|---|---|
| Potentiostatic Bare Amperometric | Dynamic software algorithm required (pH 5.5 - 8.2) | 3 - 6 Months (Mechanical self-clean) | Low sensitivity to turbidity; prone to Cu²⁺, Fe³⁺ | Secondary municipal booster stations & cooling towers |
| Membrane Polarographic Probe | Requires narrow pH buffer or dual pH/temp input | 1 - 2 Months (Membrane/Electrolyte replacement) | Protected against dissolved metals; fouled by fats/oils | Pure drinking water networks & industrial effluent loops |
| DPD Photometric Wet Chemistry | Independent (Reagent buffers sample to pH 6.3 - 6.6) | 30 Days (Reagent replenish & peristaltic tube check) | High turbidity causes scattering; oxidized manganese | EPA / WHO regulatory compliance outfalls & plant inlets |
Localized Process Integration
Critical Industrial & Municipal Duty Profiles
Residual chlorine monitors operate under widely disparate water matrix conditions across varying regional guidelines and process extremes.
Municipal Potable Water
Compliant with WHO guidance (holding residual free chlorine ≥0.5 mg/L after 30 mins contact at pH <8.0). Prevents pathogen regrowth across lengthy distribution pipe networks while avoiding trihalomethane (THM) disinfection byproducts.
Cooling Tower Biocide Loops
Automates the slug-dosing of sodium hypochlorite or chlorine dioxide to eliminate Legionella pneumophila while limiting excessive oxidant levels that cause accelerated microbially-induced corrosion (MIC) on copper chiller tubing.
RO Membrane Protection
Thin-film composite (TFC) polyamide Reverse Osmosis membranes degrade rapidly when exposed to >0.1 ppm free chlorine. In-line amperometric monitors verify complete sodium metabisulfite (SMBS) dechlorination before feed water enters expensive RO vessels.
Commercial Aquatic Facilities
Maintains tight synergy between free available chlorine and combined chlorine (chloramines). Coupled with pH transmitters, systems eliminate mucous membrane irritation and eye burn for bathers while ensuring bacteriological compliance.
Supply Chain Resilience & Production Scale
China Factory Direct: Pudong & Lingang Manufacturing Core
Leveraging two fully certified facilities in Kangqiao and Lingang, Shanghai Boqu Instrument Co., Ltd. eliminates middleman costs with vertical integration spanning PCB layout, glassblowing, and multi-gas injection.
2007
Founded In Shanghai
4,632
Floor Area (m²)
100k+
Annual Unit Output
100+
Export Countries
2,000+
Enterprise Clients
Component Traceability
All analog-to-digital converters, potentiostatic conditioning chips, and quartz flow-cell manifolds are source-verified. Complete assembly takes place on automated SMT lines with 100% optical inspection.
Environmental Burn-in
Every manufactured residual chlorine monitor and high-temperature probe undergoes a compulsory 48-hour continuous thermal and electronic aging chamber test to eradicate infantile component failure before global export.
OEM / ODM Custom Engineering
Full firmware and hardware customization: private-labeled front panels, custom Modbus register addresses, broad-spectrum power configurations (24VDC, 110VAC, 220VAC), and customized flow-cell mechanics.
Compliance, Telemetry & Integration
International Certifications & Edge IIoT Connectivity
Engineered to comply with stringent water safety frameworks globally including US EPA Method 334.0, European EN 61010-1 electrical norms, and ISO 14001 manufacturing standards.
Telemetry & Edge Fieldbus
Designed for native PLC and DCS integration: dual isolated 4-20mA current loops with configurable zero/span, 2 SPDT relay contact outputs for high/low disinfectant alarms, and RS485 Modbus RTU communication for long-distance remote telemetry units (RTUs).
EPA Method 334.0 Quality Control
Supports documented on-line verification procedures mandated by municipal authorities. Enables regular comparative grab-sample calibration without interrupting continuous baseline monitoring records or causing process loop disruptions.
Explosion-Proof & Enclosure Grades
Enclosed in flame-retardant, high-impact polycarbonate or aluminum die-cast housings rated IP65/NEMA 4X. Corrosion-proof against saline coastal environments, aggressive chlorine gas fumes, and outdoor sun exposure in water facilities.
Wholesale Buyer Intelligence
Residual Chlorine Monitoring: Engineering FAQ
Comprehensive procurement and technical responses compiled by BOQU’s application and export engineering team.
How does sample pH affect free residual chlorine measurement accuracy?
Free chlorine exists in aqueous equilibrium between Hypochlorous Acid (HOCl) and Hypochlorite Ion (OCl⁻):
Cl₂ + H₂O ↔ HOCl + H⁺ + Cl⁻. Amperometric sensors measure HOCl reduction directly because HOCl permeates membranes and reacts on electrodes drastically faster than OCl⁻. At pH 6.5, ~90% of free chlorine is HOCl; at pH 8.0, HOCl drops to ~20%. Without automated pH compensation, a rise in water pH causes amperometric analyzers to report artificially low free chlorine values despite adequate total oxidant capacity. Our controllers utilize real-time pH electrode readings paired with dynamic algorithms to output true Free Chlorine levels.
Is BOQU a primary manufacturer or an intermediary distributor?
Shanghai Boqu Instrument Co., Ltd. is a verified, primary manufacturer founded in 2007. Operating across two modern manufacturing facilities in Shanghai (Kangqiao Town and Lingang Special Area) spanning 4,632 square meters, BOQU maintains end-to-end control across glass electrode fabrication, plastic injection molding, PCB assembly, firmware engineering, and ISO 9001 quality calibration benches.
What minimum flow rate is necessary across the sensing chamber?
Amperometric sensors consume chlorine at the cathode surface during measurement. If water sample flow stagnates, a depleted boundary layer forms, yielding false low readings. BOQU flow-cell assemblies are hydrodynamically engineered to maintain laminar flow between 30 to 60 L/h across the working electrode interface. Optional continuous rotameter float indicators with limit switches provide automated interlocks to prevent dosing runaway during line stoppages.
What is the standard delivery timeline for wholesale and OEM orders?
Standard inventory analyzers and electrodes typically ship within 3–5 business days. Bulk wholesale orders (50–500 units) and customized OEM configurations (custom private labels, tailored casing designs, and specialized firmware parameter maps) maintain predictable lead times of 2 to 3 weeks, expedited by our deep domestic component supply chain based in Shanghai.
Can the chlorine monitor operate directly in high-temperature or fermentation duty?
Chlorine monitors require process temperatures below 50°C to preserve reference electrolyte integrity and avoid rapid chemical decomposition of disinfectant species. However, for specialized biopharma fermentation lines or hot process steam water loops, BOQU manufactures specialized high-temperature pH and dissolved oxygen probes (e.g., pH5806 and DOG-208FA) rated to withstand continuous temperatures up to 130°C and repetitive steam-in-place (SIP) sterilization cycles.
Factory Direct Catalogue
Wholesale Sensor & Online Analyzer Sourcing Portfolio
Equip your municipal water distribution plants, fermentation bioreactors, or automated dosing systems with certified, factory-direct water quality instrumentation.
High-Temp (0-130℃) pH Sensor
Direct factory supply for steam-sterilizable biotechnology fermenters, bioreactors, and hot process fluids.
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S8 Connector High-Temp pH Probe
Equipped with an internationally standardized PG13.5 thread and S8 plug-in head for hassle-free field retrofit.
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SWAS Silicate / Phosphate Analyzer
Ultra-low trace level monitoring safeguarding thermal power turbines and high-pressure steam boilers against silica scale.
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TOC-3042 Online TOC Analyzer
Precision Total Organic Carbon verification for USP purified water, WFI loops, and deionized water networks.
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SJG-2083CS Acid/Alkali Meter
Inductive toroidal conductivity system measuring chemical concentrations for food CIP loops and demineralizers.
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Online COD / TP / TN Analyzer
Automated wet-chemistry digestion analyzer ensuring continuous municipal and chemical outfall permit compliance.
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pHG-2081Pro Industrial Transmitter
Rugged IP65 controller handling pH/ORP inputs with isolated 4-20mA, Modbus RS485, and dual setpoint relays.
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DOG-208FA High-Temp DO Sensor
Polarographic dissolved oxygen sensor resistant against harsh steam-in-place sterilization in industrial biopharma fermenters.
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