A20PR-PROFESSIONAL pH/ORP CONTROLLER

The A20PR pH/ORP Controller is made for workers who need to control water quality precisely and reliably. This controller keeps your pH and ORP levels in the right amounts 24 hours a day, 7 days a week, whether you’re in charge of a wastewater treatment plant, a chemical processing plant, or an aquaculture system.

The A20PR works great in tough places like municipal water plants, pharmaceutical factories, food processing plants, and environmental monitoring stations. It is trusted by water treatment pros in more than 40 countries.

★★★★★

  • Short delivery time
  • Better price
  • Customizable parameters

Features

  • Language support: Default standard Chinese interface, switchable to English interface.
  • Diverse temperature compensation methods: PT1000, NTC10K, and manual temperature compensation are available.
  • One 4-20mA output (optional 4-20mA output or RS-485 communication), corresponding to PH/ORP values ​​or temperature.
  • Relay high/low point switching is free; hysteresis is freely adjustable to prevent relay-induced circuit breaker interruption.
  • Password management function to prevent accidental operation by non-professionals.
  • Menu prompt function for user operation.

Specifications

Measuring rangePH（0—14PH，0.0—14.0PH，0.00—14.00PH ）
ORP( -1999 — +1999 MV)
Accuracy±0.01 pH; ±1 mV
Resolution0.01 pH; 1 mV
Stability≤ 0.02 pH/24 hours; ≤ 3 mV/24 hours
Temperature Compensation0–100 °C Manual / Automatic (PT1000/NTC10K)
Signal Output4–20mA isolated protection output, independently corresponding to pH/ORP or temperature, with a load capacity up to 500Ω
Alarm OutputTwo sets of high/low point alarms (3A/250 V AC) normally open contact relay, one set of self-cleaning
Power SupplyAC220V or DC24V
Power Consumption≤ 5W
Environmental ConditionsTemperature: 0–60 °C; Humidity ≤ 85% RH
Overall Dimensions144 × 144× 115mm (Height × Width × Depth)
Opening Size138 × 138 mm (height × width)

Where is A20PR Used?

Treatment plants for wastewater

Check the pH of the wastewater to make sure it meets regulations before it is released.

Fish farms and aquaculture

Keep the water in good shape so fish can grow properly.

Treatment of Drinking Water

Make sure that the pH values in city water sources are safe.

Making pharmaceuticals

Validated pH tracking will help you meet GMP standards.

Food and Beverage Processing

When making beer, milk, or drinks, you need to control the pH.

Production of Chemicals

Accurate pH control to improve reaction performance and product quality

Not sure if A20PR will work for you? Get in touch with us to set up a free consulting.

Why choose A20PR

  • Excellent measurement performance: ± 0.01 pH high accuracy and ≤ 0.1 pH/24h stability, offering dependable data support for critical industrial processes.
  • Robust environmental adaptability: Isolation signal transmission technology combined with anti-interference design guarantees stable performance in complex industrial electromagnetic settings.
  • User-friendly operation: intuitive menu prompts, password protection, and storage of 60 alarm records streamline device management and facilitate fault analysis.
  • Flexible customization: Multiple installation modes, compensation methods, and display options to meet the personalized requirements of different industries and scenarios.
  • Cost-effective solution: rapid delivery cycle, competitive pricing, and minimal maintenance expenses, thereby decreasing the total operational costs of the enterprise.

A20PR vs Standard pH/ORP Analyzer

Application scenariosA20PR AdvantagesCommon products
Chemical workshop (high interference)Isolation output+dedicated cable, data fluctuation ≤ ± 0.02pH/24hVulnerable to electromagnetic interference and large data drift
Municipal wastewater treatment plant (humid environment)Waterproof junction box+leak proof installation, no risk of short circuitThe wiring is prone to moisture and has a high failure rate
Multinational factories (multilingual requirements)One click switching between Chinese and English, with no communication barriers during operationNeed to restart the device to switch, the process is cumbersome
Novice operator (non professional)Menu preview+prompt function, calibration completed in 3 stepsThe menu hierarchy is complex and prone to incorrect operation

Technical Support

1. Clean the electrode after preheating; 2. Immerse in 4.00 pH standard solution, press confirm once the mV value stabilizes; 3. After rinsing, immerse in 6.86 pH standard solution, press confirm once stabilized.

The A20PR can keep an eye on both factors at the same time:
On a range from 0 to 14, pH Mode tells you how acidic or basic a solution is. It’s necessary for processes like wastewater treatment and food preparation where accurate pH control is needed for chemical reactions, product quality, or following the rules.
The ORP Mode (Oxidation-Reduction Potential) tells you how well the water can oxidize or reduce pollutants. It is measured in millivolts (-2000 to +2000mV). ORP is very important for keeping an eye on cleaning, figuring out how well chlorine is working, and managing chemical reactions in places like keeping pools clean and treating wastewater from factories.
Since it can do two things at once, it doesn’t need two different controllers. This saves money on tools and panel room.

Calibration frequency depends on your application’s criticality and environmental conditions. We recommend:
Critical applications (pharmaceutical, drinking water): Monthly calibration
Industrial processes (wastewater, chemical): Quarterly calibration
General monitoring: Every 6 months
The A20PR stores calibration data with timestamps and can be programmed to send reminder alerts. Factors like high temperatures, chemical exposure, or frequent electrode cleaning may require more frequent calibration.

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Choose the A20PR for pinpoint-accurate, no-fuss water quality monitoring

If you work in a chemical plant or a city water system that never sleeps, the A20PR changes the way industrial-grade pH/ORP tracking is done with three great features: rock-solid reliability, plug-and-play freedom, and an easy-to-use design that doesn’t require a PhD. With an accuracy of ±0.01pH, it picks up on small changes in the water quality that other instruments miss. Its 7 display modes can be used with any electrode and any level of accuracy, and its built-in menu previews and language switching (English/Chinese) make setup easy, even for beginners. With three temperature adjustments, separate anti-interference signals, and two mounting choices (panel or wall-mount), this thing works great in places with a lot of noise and humidity, cutting down on downtime by 35%.

Hundreds of teams in every field believe it, and the results are clear: Water compliance rates went up by 10%, on-site calibrations could be done 85% faster, and repair teams had half as much work to do. If you need to keep production on track, follow all the rules, or save money, the A20PR is your best friend. That way, you can always be sure that the water is clean.

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