Why the PD1P1 Excels in Harsh pH Monitoring Environments

When process fluids range from -2.0 to 14.0 pH and temperatures hit 105 °C, standard sensors fail. The PD1P1 HACH analog differential pH sensor handles these extremes with ±0.02 pH accuracy. Its PEEK body resists chemical attack, while the titanium ground electrode ensures long-term stability. For engineers managing water treatment or chemical processing, this sensor offers reliable performance where others degrade quickly.

Key Features and Technical Specs of the PD1P1

• Range: -2.0 to 14.0 pH with ±0.02 pH accuracy.
• Drift: 0.03 pH per 24 hours, non-cumulative.
• Temperature compensation: automatic with NTC 300 Ω thermistor.
• Cable: 4.5 m, 5-conductor with XLPE jacket rated to 150 °C.
• Pressure: max. 10.7 bar sensor only.
• Weight: 0.9534 kg; diameter: 34.9 mm; length: 196.3 mm.
• Sensor thread: 1" NPT at both ends for flexible mounting.

One standout spec is the automatic temperature compensation with selectable correction factors for ammonia, morpholine, or user-defined pH/°C linear slope. This allows precise pure water compensation from 0.0 to 50 °C, reducing drift in variable-temperature streams.

Applications and Use Cases for the PD1P1

In wastewater treatment, the PD1P1 monitors pH across aeration basins and effluent channels. Its wide range and high accuracy make it suitable for chemical dosing control. For power plants, the sensor handles high-purity water loops where temperature compensation is critical. The convertible mounting option simplifies installation in pipes or tanks.

Installation Guide for the PD1P1

Mount the sensor using the 1" NPT threads at either end. Ensure the cable is routed without sharp bends to protect the XLPE jacket. For submersion, use the convertible mounting hardware (check pressure rating separately). Calibrate using two-point automatic or manual methods as needed. Verify the NTC 300 Ω thermistor is connected for automatic temperature compensation.

Maintenance and Reliability Tips

Inspect the sensor body and ground electrode periodically for fouling. The PEEK material resists most chemicals, but heavy scaling may require cleaning. The non-cumulative drift of 0.03 pH per 24 hours means recalibration intervals can be extended in stable processes. For high-temperature applications (up to 105 °C), verify cable jacket integrity regularly.

Compatibility and Integration

The PD1P1 uses analog communication via a 5-conductor cable. It works with HACH analyzers that support NTC 300 Ω thermistor temperature input. For systems requiring MODBUS, pair with a compatible HACH transmitter. The sensor is designed for direct connection to analog pH controllers.

FAQ about the PD1P1

Q: What is the operating temperature range of the PD1P1?

A: The sensor operates from -5 to 105 °C.

Q: How accurate is the PD1P1 pH measurement?

A: Accuracy is ±0.02 pH across the full range.

Q: What cable length is included with the PD1P1?

A: The sensor comes with a 4.5 m cable.

Q: Can the PD1P1 be used in high-pressure applications?

A: Yes, up to 10.7 bar for the sensor only; check mounting hardware separately.

Q: What temperature sensor is built into the PD1P1?

A: An NTC 300 Ohm thermistor for automatic compensation.

Q: Is the PD1P1 compatible with MODBUS systems?

A: Yes, the sensor supports MODBUS communication.

Product Support and Availability

The PD1P1 is in stock and ready to ship from PetroPartsOnline. Contact our team for technical support or to verify compatibility with your existing HACH analyzer. We provide fast delivery for industrial maintenance needs.