A rugged digital pH electrode with matching pin for field measurements
The Hanna Instruments HI12301 is a digital, double-junction, gel-filled pH electrode with a durable PEI (polyetherimide) body. It also has a built-in temperature sensor, so one probe handles pH and temperature compensation.
A microchip inside the electrode stores the sensor type, serial number and calibration data, and all pH measurements are made inside the electrode and sent digitally to the meter. Because the meter reads the calibration from the probe, you can swap electrodes without recalibrating. It connects through a 3.5 mm connector for meters that use Hanna digital electrodes.
Key features
- Digital electrode: The built-in microchip stores calibration information (date, time, offset, slope, probe condition and buffers used), and the meter retrieves it automatically.
- Matching pin and Sensor Check: The matching pin checks the impedance between the indicating and reference electrodes, so a compatible meter can flag a cracked sensing glass or a poor reference junction.
- Double junction reference: The inner compartment holds silver ions and the outer electrolyte is silver-free, so very little silver reaches the sample.
- Gel-filled: A gel electrolyte reduces maintenance compared with a refillable electrode.
- Durable PEI body: Hanna describes it as chemically resistant, with shielding around the tip to reduce breakage from bumps and drops.
- Spherical glass tip: The 7.5 mm bulb gives a wide area of sample contact for faster response and stable readings, according to Hanna.
- Built-in thermistor: Temperature compensation from the same probe.
Ideal for
- Field pH measurements
- Industrial applications
- Labs and field teams that want to swap probes without recalibrating
Technical specifications
| Brand | Hanna Instruments |
|---|---|
| Model / item number | HI12301 |
| Measurement range | pH 0 to 13 |
| Reference | Double junction |
| Junction | Ceramic, single; flow rate 15-20 µL/h |
| Electrolyte | Gel |
| Body material | PEI (polyetherimide) |
| Tip shape | Spherical, 7.5 mm diameter |
| Matching pin | Yes (Sensor Check) |
| Temperature sensor | Built-in thermistor |
| Operating temperature | -5 to 70 °C (23 to 158 °F), low-temperature glass |
| Maximum pressure | 2 bar |
| Body length | 120 mm |
| Overall length | 181 mm |
| Outer diameter | 12 mm |
| Cable length | 1 m |
| Connector | 3.5 mm, for meters that use Hanna digital electrodes |
| Digital electrode | Yes, built-in microchip stores calibration data |
| Recommended use | Field applications |
| Weight | 0.32 kg (0.71 lb) |
What's included
- HI12301 digital PEI body pH electrode with 1 m cable and 3.5 mm connector
Compatibility
The 3.5 mm connector is proprietary to meters that use Hanna digital electrodes. Check that your meter supports digital electrodes, and Sensor Check if you want to use the matching pin. Contact Delta Scientific if you are unsure which meter you need.









