Advantage of flat tip electrodes

• In a continuous in-line installation, the glass sensor of the pH electrode can be physically damaged by solution streams containing suspended solids.

• Our Flat Tip electrodes are the best answer to this problem. The flat tip virtually eliminates deposits that can foul the electrode, significantly reducing necessary maintenance.

• This characteristic makes flat tip electrodes ideal for continuous in-line monitoring and for solutions containing aggressive chemicals.

Each pH electrode is provided with an internal matching pin that can avoid typical problems caused by grounding loop current, such as:

• progressive damage of the electrode
• fluctuating measurements
• poor process regulation

In many industrial applications, especially in plating baths, grounding loop current is a very common problem.
When a traditional electrode/controller system is used with the electrode reference connected both to the electrode and to the instrument, a current flow occurs through the reference half cell, causing fluctuations in reading and serious damage to the Ag/AgCl element. The potential matching pin shields the reference from external electrical fields. Shown above, the matching pin allows the measurement to stabilize and ensures effective process regulation. In order to function properly, the matching pin has to be continuously immersed in the measured solution and for this reason is placed near the electrode junction.

Installation

These electrodes have been designed with ¾” external thread on both ends for easy installation. HANNA instruments® also provides a series of probe holders for in-line, tank or by-pass installations for these electrodes, as shown below.

Front thread ¾” NPT

• Direct in-line installation ¾” standard tee 
• Immersion installation in vessel, tank, plating bath with HI 60501 (PVC) or HI 60503 (PVDF) electrode holders with adjustable immersion level: min 10 cm, max 70 cm 
• Direct pipe installation with HI 60542 PVC electrode holder, 2″ thread

Back thread ¾” NPT

• Immersion installation with ¾” threaded pipe 
• By-pass installation with HI 60545 By-pass electrode holder “Loop” configuration Liquid inlet: ¾” Liquid outlet: ¾

Junction

Three junction types are available:

•  Annular non-clogging PTFE junction, for testing solutions with high content of suspended solids or for high pressure installation
• Open junction, ideal for wastewater analysis
• Ceramic junction

Glass Sensor

• Hanna has developed four types of specialized glass. First is a durable sensor glass for general purpose, industrial use. This glass can withstand the stress of daily use. The remaining types of electrode glass allow continuous monitoring in highly acidic solutions containing fluoride ions, as well as high or low temperature process and streams significantly increase the electrode life

Temperature Sensor

• The pH electrodes with built-in 3-wire Pt100 or Pt1000 temperature sensor allow for the temperature compensation of pH readings as well as temperature measurements.

Connection Type

• Electrodes are wired for direct connection to a transmitter or process controller, or with the standard BNC connector.

Built-in Amplifier

• Models with a built-in amplifier are necessary for long distance measurements, where it is not possible to install a transmitter. The internal amplifier can be powered directly from select Hanna process controllers or a power source that supplies the appropriate voltage.

Cable Length

• Non-amplified electrodes are provided with a 5, 10 or 15 m cable (16’, 33’ or 49’)

PVDF Body

• The PVDF body used for the Flat Tip Series withstands high pressure and high temperature applications, and guarantees a high chemical and mechanical resistance. These characteristics makes the PVDF material the most recommended for many industrial applications. PVDF is also non-toxic and compatible with food applications.