Dule Channels Analog PH And ORP Controller With RS485 For Industrial Wastewater Treatment
Daruifuno brand APX2-PD dual-channel controller usually supports simultaneous connection of one analog pH electrode and one analog ORP (oxidation-reduction potential) electrode, or two analog pH sensors and two analog ORP sensors. The pH value and oxidation-reduction potential (mV value) of the solution are collected respectively. The internal analog circuit converts the electrode signal into a standard voltage signal, amplifies and filters it, and then the microprocessor of the controller performs numerical processing and judgment, thereby outputting a relay control signal or an analog current (such as 4-20mA) signal.
 pH channel: measures pH (0-14) and controls acid/base dosing.
 ORP channel: measures oxidation-reduction potential (±2000mV) for disinfection (such as chlorination) or dechlorination.
 The electrode is connected to the controller terminal; the controller relay output is connected to the dosing pump, alarm or cleaning device; the control logic, calibration, cleaning cycle, etc. can be set through the menu; regular calibration and data viewing are supported.
Product Parameters
| Model | APX2-PD-A | APX2-PD-D | |
| Measuring Objects | 2 measurement channel inputs, pH or ORP can be selected arbitrarily | ||
| Principle | PH | Glass pH electrode (hydrogen ion concentration index) | |
| ORP | Platinum or gold electrodes (redox potential) | ||
| Display Range | PH: 0~14pH ORP: ± 2000mV Temp: -10~150℃ | ||
| Resolution | PH: 0.01pH ORP: 1mV TEMP: 0.1℃ | ||
| Accuracy | 0.1% of the measuring range or ±0.02pH / ±2mV, take the larger one | ||
| Stability | 0.05% of measuring range every 24 hours without accumulation | ||
| Repeatability | Better than 0.1% of measuring range | ||
| Temp. Compensation | Automatic or manual (NTC10K/PT1000) | ||
| Relay Output | Two SPST relays, Max. load 3A/250VAC, set high/low alarm, temp. or clean control | ||
| Digital Communication | A two-wire RS485 interface, Modbus RTU and JSON | ||
| Current Output | Two 0/4~20mA current Max. load 1000Ω | ||
| Time Display | Year/month/date hour/minute/second | ||
| Historical Data | Record 10000 historical data and the last 100 calibration maintenance data | ||
| Valuation Object* | Built-in matrix (equivalent to residual chlorine) 0~2.5mg/L | ||
| Support user-defined (20x20 matrix) | |||
| Linear correspondence (water sample stability) | |||
| Display | 128*64 3.2-inch graphic dot matrix LCD | ||
| Calibration Method | PH: 3 points ORP: 2 points, calibration points can be set freely | ||
| Material | Enhanced ABS Protection Grade: IP66 | ||
| Power Supply | AC: 100~240V 50/60Hz | DC: 18~36V | |
| Dimension | 144*144*120mm (Hole size 138*138mm) | ||
| Work Temperature | 0~60℃, RH<95%, non-condensing | ||
| Storage Temperature | -20~70℃, RH<55%, non-condensing | ||
| Installation | Wall mounting, pipe clamp, panel | ||
Advantages and features
Daruifuno PH ORP controller APX2-PD history record and electronic clock function1. History recording function
 1.Store measurement data, alarm events, etc.
 Recording interval can be set (such as every 10 minutes)
 2. Electronic clock function
 Real-time clock module to ensure accurate event recording time


Daruifuno PH ORP controller APX2-PD two-way relay control dosing principle
 Set the pH upper/lower limit. When the set value is exceeded, the relay will be activated.
 Example: pH > 9, start the acid dosing pump;
 pH < 6, start the alkali dosing pump;
 You can set the hysteresis interval to avoid frequent switching.

Daruifuno PH ORP controller APX2-PD automatic cleaning control principle
The cleaning relay can be set to start at a fixed time (such as every 24 hours); the flushing time setting
 starts the solenoid valve or water pump to clean the electrode
 avoids measurement errors caused by adhesion on the electrode surface.

Daruifuno PH ORP controller APX2-PD pH and ORP calibration method
 1. pH calibration:
 Use standard buffer: pH 4.01, 7.00, 10.01, PH ORP controller produced by our company Daruifuno, the calibration point can be set freely.
 Single point calibration: Use pH 7.00 liquid to calibrate the zero point.
 Two-point calibration: pH 7.00 and 4.00 or 10.00, calibrate the zero point and slope.
 The controller guides the operation, automatically determines stability and stores.
 2. ORP calibration:
 Use standard buffer, such as +220mV or +470mV.
 The calibration process is simple, usually a single point is sufficient.


Daruifuno PH ORP controller APX2-PD controller installation methodInstallation method:
 Panel installation (opening installation, IP66 protection panel)
 Wall installation (adaptive protection shell)
 Pipeline installation
 Installation environment:
 Avoid direct sunlight, high temperature and high humidity;
 Cables are routed separately to avoid sharing the same wiring trough with power lines;


Aplication:
 ◇ Surface water
 ◇ Source water
 ◇ Aquaculture waters
 ◇ Landscape water
 ◇ Import of the waterworks
◇ Water treatment monitoring
◇ Drinking water,
◇ Groundwater, swimming pool
◇Industrial process monitoring and dosing control management
◇Chemical, petroleum, paper, food and medicine, electroplating, PCB manufacturing, etc.
 ◇ Municipal/industrial water treatment
◇ Circulating cooling water monitoring
◇ Electroplating/chemical liquid control
◇ Food and beverage production line
 ◇ Acid-base neutralization reaction tank control
