Online pH meter

Overview

Online pH meterIt is an online water quality monitoring device with a microprocessor. This instrument is equipped with different types of pH (or ORP) electrodes and is widely used in various industries such as power plants, petrochemicals, metallurgical electronics, mining, papermaking, biological fermentation processes, pharmaceuticals, food and beverage, environmental water treatment, etc. It continuously monitors and controls the pH (acidity and alkalinity) value or ORP (oxidation-reduction potential) value and temperature value of aqueous solutions. Such as power plant supply water, saturated water, condensate water, general industrial water, domestic water, and wastewater.

Online pH meterThe instrument adopts LCD liquid crystal display screen; Intelligent Chinese menu operation; Equipped with 2 current outputs, freely adjustable measurement range, high and low limit alarm prompts, and two sets of relay control switches, adjustable hysteresis range, and automatic cleaning switch settings; Automatic or manual temperature compensation; Multiple automatic calibration methods for electrodes.

Two working principles

The instrument consists of signal measurement, operation, display, network communication, and panel instructions. The impedance transformation of pH and temperature transmission changes the pH to a low impedance signal of 59.16mV/pH (25 ℃); Convert NTC into a voltage signal.

The instrument is matched with a pH (or ORP) electrode to monitor the pH (or ORP) value of the solution. The sensor is a battery composed of a pH (or ORP) glass electrode and a calomel (or Ag/AgCl) reference electrode, which generates a potential difference related to the pH value of the solution based on the Nernst equation: Ex=Eo+SpH.

The potential difference is amplified by a preamplifier with high input impedance, and the thermistor sends out a signal corresponding to the temperature value. After amplification, the two sets of signals are converted from A/D and processed by an I/O interface chip through a single-chip microprocessor before being prominently displayed on the display screen.

3、 Technical parameters

01) Measurement range: pH: 0.01~14.00pHORP: -1999~+1999mV; Temperature: -5~110.0 ℃;

02）分辨率： pH：0.01pH； ORP：1mV；

03) Basic error: pH: ± 0.1pH; ORP: ± 3mV; Temperature: ± 0.5 ℃;

04) Automatic or manual temperature compensation range: -10~110 ℃;

05) Stability: pH: ≤ 0.02pH/24h; ORP: ≤2mV/24h；

06) Signal output: 4-20mA (load resistance<750 Ω); RS485 (optional)

07) Three sets of relay control contacts: 3A 240VAC, 6A 28VDC or 120VAC;

08) Power supply: 220VAC ± 10%, 50 ± 1Hz, power ≤ 3W;

24VDC， Power ≤ 1W (to be reserved); 12VDC， Power ≤ 1W (to be reserved);

9) Dimensions: 96 × 96 × 130mm;

10) Installation method: disk mounted (embedded) and wall mounted; Hole size: 91 × 91mm;

11) Instrument weight: 0.6kg;

12) Work environment:

Environmental temperature: -10~60 ℃;

Relative humidity: not exceeding 90%;

There is no strong magnetic field interference around except for the Earth's magnetic field.