Digital pH/ORP Meter for Water Testing

Digital pH/ORP meter is an industrial pH/ORP meter for water/food pH value or ORP value testing and monitoring.

Application:
Digital pH/ORP meter is widely used in the continuous testing and monitoring of pH, ORP and temperature in thermal power, chemical fertilizer, metallurgy, environmental protection, pharmaceutical, biochemical, food, drinking water, etc.

Function:

• 2.4 inch LCD display
• Good anti-interference performance
• Manual/automatic temperature compensation
• User settings: Language, buzzer, LCD backlight, password, pH/ORP electrode, manual/automatic temperature compensation, pH/ORP calibration, pH/ORP/temperature modification, pH/ORP high/low alarm, output signal 4-20mA and RS485, etc.
• Internal industrial watchdog insures pH meter doesn't crash.

Specification:

The pH meter and pH/ORP electrode selection:

The pH/ORP meter diagram of ports definition:

• INPUT: Measuring terminal of the electrode
• REF: Reference terminal of the electrode
• NC: Undefined
• TEMP2: Temperature compensation terminal 2
• TEMP1: Temperature compensation terminal 1
• RS485 (A+): RS485 communication interface A+
• RS485 (B-): RS485 communication interface B-
• 4-20mA (+): 4-20mA output terminal +
• 4-20mA (-): 4-20mA output terminal -
• AC 220V (L) or DC 24V (-): AC 220V liver wire or DC 24V negative
• AC 220V (N) or DC 24V (+): AC 220V liver wire or DC 24V positive
• LO: Normally-open relay for low alarm
• HI: Normally-closed relay for high alarm

Communication:
RS485 communication data and register address as follows:

Tips: Why should the pH meter be recalibrated?
After the calibration is completed, the frequently used pH meter does not need to be calibrated again within 48 hours. In case of any of the following situations, the meter needs to be recalibrated:

1. There's a huge difference between solution temperature and calibration temperature.
2. The electrode has been exposed in the air for too long, such as more than half an hour.
3. Position or slope adjuster is moved by mistake.
4. Peracid solution (pH＜2) or overbasic solution (pH＞12) is measured.
5. The electrode is replaced.
6. pH value of the measured solution is not in the middle of the calibrated value for two points while it's far from 7pH.