Hanna’s HI11313 refillable glass pH electrode is built for reliable, general‑purpose measurements, combining high‑temperature (HT) glass, a spherical sensing bulb, glass body, single ceramic frit, and a double‑junction reference system. Filled with 3.5M KCl electrolyte, it provides stable, accurate pH readings across a wide range of laboratory applications.

High Temperature Glass Formulation

High‑temperature glass improves electrode durability by resisting thermal stress that can shorten the life of standard pH bulbs. General‑purpose glass typically measures around 100 megaohms at 25 °C, while HT glass is closer to 400 megaohms at 25 °C, maintaining stability as temperatures rise. The HI11313 supports measurements from 0 to 100 °C, making it suitable for demanding sample conditions.

Spherical Glass Tip

The spherical sensing bulb is ideal for general‑purpose pH testing, offering consistent contact with a wide variety of sample types. While conical tips are used for penetration and flat tips for surface measurements, the spherical design provides broad compatibility and dependable performance in routine laboratory work.

Glass Body Construction

The glass body is well‑suited for laboratory environments, offering chemical resistance and easy cleaning for consistent performance. Glass also promotes rapid heat transfer to the internal reference electrolyte, helping the reference potential stabilize quickly for steady, repeatable readings.

Single Ceramic Double Junction Reference

The HI11313 uses a double‑junction reference with a single ceramic frit to maintain a steady ion flow through the junction. The ceramic material integrates cleanly with the glass body and provides a typical flow rate of 15–20 µL/hour, supporting stable readings while reducing clogging and contamination in challenging samples.

Refillable Design

This electrode is refillable with HI7082 3.5M KCl solution, a silver‑free electrolyte suited to double‑junction designs. Without silver present, the risk of silver chloride buildup at the junction is minimized, helping prevent drift and ensuring long‑term measurement reliability.

Quick Connect DIN Connector

The HI11313 features a Quick Connect DIN interface for fast, secure attachment to compatible Hanna meters such as the HI98190. This proprietary connector simplifies installation and removal while ensuring a stable electrical connection for accurate pH measurement.

Single Junction Versus Double Junction pH Electrodes

Single‑junction electrodes typically use silver‑containing fill solutions such as HI7071 (3.5M KCl + AgCl). Under harsh conditions—high pressure, high temperature, or extreme pH—sample solution can migrate into the reference compartment, contaminating the electrode and causing unstable readings.

Double‑junction electrodes add an intermediate electrolyte chamber that physically separates the reference element from the sample. This design reduces contamination risk and minimizes silver chloride precipitation, helping prevent junction clogging and improving long‑term stability in samples containing Tris buffers or heavy metals.