On-line ph sensor

1.On-line ph sensor application environment description

The on-line ph sensor is a device that measures the PH value of the solution (hydrogen ion concentration index, pH) with automatic temperature compensation function.Used for environmental water quality testing, various high/low ionic strength water sample testing, and can meet the requirements of most industrial/environmental applications for online pH measurement.

Signal output: RS485 (MODBUS-RTU), 4-20mA current output.

Low impedance sensitive glass film, internal signal isolation technology, strong anti-interference ability.

Good reproducibility, thermal stability, low drift, small size, fast response

Easy and simple installation, 3/4NPT pipe thread, convenient for submerged installation or installation in pipes and tanks, stable performance and long service life

IP68 waterproof standard

2. On-line ph sensor technical parameters

3. On-line ph sensor installation and electrical connection

1. Installation

Note: The sensor cannot be installed upside down or horizontally, but must be installed at an angle of at least 15 degrees.

2. Electrical connection

The cable is a 5-core shielded cable, and the line sequence definition is:

Brown-power line (12~24VDC) Black-ground line (GND)

Green-485B Yellow-485A

The wiring sequence should be carefully checked before powering on to avoid unnecessary losses due to wiring errors.

4. On-line ph sensor maintenance and care

When using the instrument for the first time or after long-term disuse, the sensitive bulb and reference junction should be immersed in 3.3 mol/L KCl solution for more than 2 hours.

When using, it should be washed with deionized water (or distilled water) and wiped dry to prevent impurities from entering the measured liquid. 1/3 of the sensor should be inserted into the measured liquid.

The wiring terminal part should be kept clean and dry. The sensor should be cleaned when not in use and inserted into a protective cover filled with 3.3 mol/L KCI solution, or the sensor should be inserted into a container filled with 3.3 mol/L KCI solution.

Check whether the wiring terminals are dry. If there are stains, wipe them with anhydrous alcohol and continue to use them after they are dry. The sensor should avoid being immersed in deionized water, protein solution, strong acid and alkali solution, and acidic fluoride solution for a long time, and prevent contact with silicone grease. The glass membrane of the sensor that has been used for a long time may become translucent or have sediment. At this time, it can be washed with dilute hydrochloric acid and rinsed with water.

When the sensor has been used for a long time and measurement errors occur, it can be calibrated and corrected by using the instrument. If the sensor cannot be calibrated and measured after the above maintenance and care, it means that the sensor has failed. Please replace the sensor.