PHD-99S Smart Two-Wire pH/ORP Transmitter

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PHD-99S Smart Two-Wire pH/ORP Transmitter

Product ID：ZXPH003

Price: Please inquire PDF Format

Supply Ability:50SETS/MON

Port:SHENZHEN

Product Introduction
Other information

Model NumberPHD-99S

Brand NameDONGRUN

Payment TermsTT，PAYPAL，Alibaba.com Pay

PHD-99S Smart Two-Wire pH/ORP Transmitter

Product Introduction
The PHD-99S Smart Two-Wire pH/ORP Transmitter is an industrial online monitoring instrument designed to measure and transmit pH and oxidation-reduction potential (ORP) values in industrial processes. Featuring a two-wire 24 V DC power supply, configurable 4–20 mA output, temperature compensation, and an explosion-proof enclosure, it supports continuous monitoring and process control in demanding industrial environments.
Its blue-backlit LCD displays measurement values, temperature, and output percentage. Two-button operation simplifies calibration and parameter configuration, while external magnetic adjustment supports safer operation in hazardous areas.

Performance Features
• Smart operation: Two-button calibration and parameter setting simplify commissioning and routine maintenance.
• Clear LCD display: Shows pH or ORP in mV, temperature, and output percentage.
• Two-wire transmission: Operates on 24 V DC with a configurable 4–20 mA output range.
• Flexible temperature compensation: Supports manual or automatic compensation with selectable Pt100 or Pt1000 temperature sensors.
• Safer calibration: Magnetic adjustment from outside the enclosure is available for hazardous-area operation.
• Industrial protection: IP65 enclosure protection and Ex d explosion-proof construction.

Working Principle
The transmitter receives a signal from a compatible pH or ORP electrode and processes it to determine the measured value. For pH measurement, the electrode signal corresponds to the acidity or alkalinity of the solution; for ORP measurement, it represents the solution’s oxidation-reduction potential in millivolts.
The instrument displays the measurement and temperature on its LCD and converts the measurement into a configurable 4–20 mA DC output for connection to a PLC, DCS, recorder, or compatible control system. Manual or automatic temperature compensation can be configured according to the application.

Technical Specifications

Parameter	Specification
Model	PHD-99S
Instrument Type	Smart two-wire pH/ORP transmitter
pH Measurement Range	0–14 pH
ORP Measurement Range	−1999 to +1999 mV
Measurement Error	±0.05 pH / ±2 mV
Instrument Stability	±0.05 pH / 2 mV per 24 hours
Resolution	0.01 pH / 1 mV
Display	pH or mV, temperature
Input Impedance	Greater than 3 × 10¹² Ω
Output Signal	4–20 mA DC
Output Load Resistance	0–500 Ω
Power Supply	24 V DC ±10%
Operating Temperature	−10°C to +55°C
Temperature Compensation Sensor	Pt100 or Pt1000
Temperature Compensation Range	−10°C to +100°C
Temperature Compensation Error	Less than 0.005 pH/°C
Temperature Compensation Mode	Manual or automatic
Electrical Connection	M20 × 1.5
Protection Rating	IP65
Explosion-Proof Rating	Ex d IIC T6 Gb

Application Scenarios
The PHD-99S industrial pH/ORP transmitter is suitable for:
• Wastewater treatment: Online pH monitoring and neutralization control.
• Effluent monitoring: Monitoring pH and ORP during industrial wastewater discharge management.
• Water purification: Monitoring water quality in treatment processes.
• Chemical processing: pH and ORP monitoring during chemical reactions.
• Acid–alkali neutralization: Supporting automated dosing and process regulation.
• Hazardous industrial areas: Applications requiring compatible explosion-proof instrumentation.

Comparison with Other Monitoring Solutions

Feature	PHD-99S Smart pH/ORP Transmitter	Conventional pH Transmitter	Laboratory pH Meter
Primary Use	Industrial online pH/ORP monitoring	Industrial pH monitoring	Laboratory measurements
Measurement	pH and ORP	Typically pH, depending on model	Usually pH; ORP depends on model
Signal Output	Configurable 4–20 mA	Model-dependent	Model-dependent
Power Supply	24 V DC, two-wire	Model-dependent	Often standalone power
Temperature Compensation	Manual or automatic; Pt100/Pt1000	Model-dependent	Often available
Hazardous-Area Design	Ex d IIC T6 Gb specified	Depends on certification	Generally intended for laboratory use
Typical Application	Continuous process monitoring and control	Industrial process monitoring	Sample testing and laboratory analysis

Frequently Asked Questions
Q1: What does the PHD-99S transmitter measure?
It measures pH from 0 to 14 pH and ORP from −1999 to +1999 mV.
Q2: What output signal does it provide?
It provides a 4–20 mA DC output with a configurable corresponding measurement range.
Q3: What power supply does the transmitter require?
It operates on a 24 V DC supply with a tolerance of ±10%.
Q4: Does the PHD-99S support temperature compensation?
Yes. It supports manual or automatic temperature compensation and can be configured for Pt100 or Pt1000 temperature sensors.
Q5: What information appears on the LCD?
The blue-backlit LCD displays the pH or ORP measurement, temperature, and output percentage.
Q6: Can the transmitter be adjusted in hazardous areas?
The instrument supports external magnetic adjustment using a magnetic wand, allowing calibration and parameter changes without opening the enclosure. Follow the applicable hazardous-area operating procedures.
Q7: What is its protection rating?
The specified enclosure protection rating is IP65, and the explosion-proof rating is Ex d IIC T6 Gb.
Q8: Which applications are suitable for this transmitter?
Typical applications include wastewater treatment, water purification, acid–alkali neutralization, chemical processing, and industrial online pH/ORP control.

Frequently Asked Questions
Q1: What does the PHD-99S transmitter measure?
It measures pH from 0 to 14 pH and ORP from −1999 to +1999 mV.
Q2: What output signal does it provide?
It provides a 4–20 mA DC output with a configurable corresponding measurement range.
Q3: What power supply does the transmitter require?
It operates on a 24 V DC supply with a tolerance of ±10%.
Q4: Does the PHD-99S support temperature compensation?
Yes. It supports manual or automatic temperature compensation and can be configured for Pt100 or Pt1000 temperature sensors.
Q5: What information appears on the LCD?
The blue-backlit LCD displays the pH or ORP measurement, temperature, and output percentage.
Q6: Can the transmitter be adjusted in hazardous areas?
The instrument supports external magnetic adjustment using a magnetic wand, allowing calibration and parameter changes without opening the enclosure. Follow the applicable hazardous-area operating procedures.
Q7: What is its protection rating?
The specified enclosure protection rating is IP65, and the explosion-proof rating is Ex d IIC T6 Gb.
Q8: Which applications are suitable for this transmitter?
Typical applications include wastewater treatment, water purification, acid–alkali neutralization, chemical processing, and industrial online pH/ORP control.