31050381 HONEYWELL

This electrode belongs to the Meredian I family of pH sensors. It is a "combination" electrode, meaning it contains both the glass measuring electrode and a reference electrode within a single body. This specific model features a glass body construction and is integrated with an Automatic Temperature Compensator (ATC) to ensure that pH readings remain accurate regardless of temperature fluctuations in the process liquid. It comes with a 12-foot (approximately 3.66 meters) cable with tinned leads for easy integration into industrial transmitters or controllers.

Product Parameters

• Electrode Type: Glass Combination with Automatic Temperature Compensation (ATC)

• Measurement Range: 0 to 14 pH

• Operating Temperature: 10°C to 80°C ($50 \text{°F}$ to $176 \text{°F}$)

• Pressure Rating: Designed for processes under pressure up to 50 psig (when used with compatible 7774 assemblies)

• Body Material: Glass with specialized internal reference fill

• Cable Length: 12 feet (3.66 meters)

• Connection Type: Tinned leads for terminal block connection

• Mounting Compatibility: Fits Honeywell 7774 and 7774D stainless steel insertion/removal ball valve assemblies

• Mechanical Connection: Compatible with 1.25-inch or 1.5-inch NPT connections

Product Advantages

• Accurate Temperature Compensation: The built-in ATC allows the sensor to automatically adjust the pH signal for temperature-induced errors, providing stable readings in dynamic thermal environments.

• Rugged Meredian Technology: Honeywell’s Meredian technology utilizes a unique reference junction design that minimizes clogging and poisoning, leading to a longer service life compared to standard industrial electrodes.

• Ease of Maintenance: When used with the 7774 ball valve assembly, this electrode can be inserted or removed from a pressurized pipeline without shutting down the process, significantly reducing maintenance downtime.

• Versatile Orientation: The electrode is designed to function effectively in any position—vertical, horizontal, or at an angle—making it suitable for diverse piping and tank configurations.

• High Chemical Resistance: The glass combination construction provides excellent resistance to a wide range of corrosive chemical processes.

Important Considerations and Precautions

• Handling Fragility: As a glass electrode, the sensing bulb is extremely fragile. Avoid any physical impact and never wipe the glass bulb with a dry cloth, as static charge or scratches can permanently damage the sensor.

• Storage and Hydration: The electrode must never be allowed to dry out. It should always be stored in a suitable hydration solution (typically $4.0 \text{ pH}$ buffer or $KCl$ solution) when not in use. If the electrode dries out, it may require a long soaking period to restore functionality, or it may fail entirely.

• Pressure Limits: Do not exceed the 50 psig pressure rating. Operating beyond this limit risks breaking the glass body or causing seal failure within the mounting assembly.

• Interference: Ensure the cable is routed away from high-voltage power lines or variable frequency drives (VFDs) to prevent electrical noise from distorting the sensitive millivolt signal of the pH electrode.

• Calibration: Regular calibration using standard buffer solutions (e.g., pH 4.0, 7.0, and 10.0) is necessary to maintain accuracy, as all pH electrodes naturally drift over time.

Product Applications

The 31050381-501 is primarily used in industrial sectors where process liquid monitoring is essential for quality control or environmental compliance.

• Water and Wastewater Treatment: Monitoring the pH of influent and effluent streams to ensure effective neutralization and compliance with discharge permits.

• Chemical Manufacturing: Managing the acidity or alkalinity of reaction vessels and process loops in real-time.

• Power Plant Water Chemistry: Controlling the pH of boiler feed water and cooling tower water to prevent scale build-up and corrosion.

• Pulp and Paper: Monitoring bleach plant processes and wastewater neutralization.

• Food and Beverage: Used in Clean-in-Place (CIP) systems to monitor cleaning solution concentrations and final rinse water quality.