
Hanna Instruments HI-12301 pH Edge Electrode with Sensor Check™
The HI-12301 is a smart pH electrode for use with the HI-2020 Edge hybrid meter.
The HI-12301 is a plastic body, double junction, gel filled pH electrode with a matching pin and built-in temperature sensor for temperature compensated measurements in a single probe design. This probe features a 3.5 mm connector designed exclusively to be used with Hanna Instruments edge® Tablet Meters.
This electrode features a built-in microchip that stores sensor type, ID, and calibration information that is automatically retrieved by Edge once the electrode is plugged in.
Stored pH calibration information includes: calibrated buffers, date, time, offset and slope characteristics of the electrode.
The HI-12301 features an easy to plug in 3.5mm connector and is recommended for use in field applications.
The HI-12301 electrode features a built-in microchip that stores sensor type, serial number, and calibration information. It also features a single ceramic junction and the spherical pH sensing portion is made with general purpose glass. The electrode has a rugged PEI (polyetherimide) body that has the chemical resistance of a glass body in an unbreakable plastic making it ideal for field and industrial applications.
The matching pin integrated into the HI-12301 is for the Sensor Check™ capability of the edge pH meter. This feature is used to identify problems with the pH electrode such as cracks in the sensing glass or poor condition of the reference junction.
Built-In Microchip
A built-in microchip stores the sensor type, serial number and calibration information including date, time, offset, slope, probe condition and buffers used. This information is automatically retrieved by edge® once the electrode is plugged in. The ability to transfer information allows for hot swapping of probes without having to recalibrate. All pH measurements are performed within the electrode and transferred digitally to the meter. This overcomes any noise issues associated with the traditional high impedance analogue measuring system. Electrical noise can be generated from a built in temperature sensor and while working in a humid environment.
Spherical Glass Tip
The spherical shaped tip design allows for a wide area of contact with the sample. This permits a faster electrode response with a higher degree of stability. The tip uses a glass formulation that has a resistance of approximately 100 megaohms. This means that measuring conditions are optimal around ambient temperatures. Use of high or low temperature glass around ambient temperatures would not be optimal due to a long response time or a shortened lifespan of the electrode.
Double Junction Reference
A double junction electrode has an internal compartment surrounding the reference wire. Silver ions are present in the electrolyte of the internal compartment, which houses the Ag/AgCl reference wire; the electrolyte outside this compartment is silver free. The double junction design means that virtually no silver from the electrode enters the sample. This design allows measurement in applications where silver ions in the sample are undesirable or silver precipitates on the junction are likely to form.
PEI Electrode Body
The PEI (polyetherimide) electrode body is suitable for a wide range of applications and excels in field measurements due to its durability. The shielding around the spherical glass tip minimises breakage due to accidental bumping or dropping of the electrode. The PEI plastic is a high quality plastic that is chemically resistant to many harsh chemicals.
Matching Pin
The HI-12301 integrates a matching pin into the electrode and is part of the Hanna Instruments Sensor Check™ feature. The matching pin checks the impedance across the indicating and reference electrodes. This allows the edge meter to alert the user in the event that the glass of the indicating pH electrode is cracked and the condition of the reference junction.
Built-In Temperature Sensor
HI-12301 features a built-in thermistor temperature sensor that is in the tip of the indicating pH electrode. A thermistor temperature sensor provides for a high accuracy temperature reading and should be as close as possible to the indicating pH electrode in order to compensate for the effect that temperature has on the membrane potential. By having an accurate reading it is possible to provide an accurate temperature compensated reading.
3.5 Connection – Phono plug electrode connection used on HANNA smart Edge electrodes. Provides a secure, easy-to-use connection.
Specifications
| Description | combination, digital pH electrode |
| Reference | double, Ag/AgCl |
| Junction | ceramic, single / 15-20 uL/h |
| Electrolyte | gel |
| Max Pressure | 2 bar |
| Range | pH: 0 to 13 |
| Recommended Operating Temp. | -5 to 70°C |
| Tip/Shape | spheric (dia: 7.5 mm) |
| Temperature Sensor | yes |
| Matching Pin | yes |
| Amplifier | yes |
| Body Material | PEI |
| Cable | 1m |
| Recommended Use | field applications |
| Connection | 3.5mm jack |

Frequently Asked Questions
Clear answers to help you choose the right water testing solution with confidence
Which brands of water testing kits do you supply?
Do you provide kits for both home and professional use?
Yes — whether you’re a pool or spa owner, aquarium keeper, utility company, or a university laboratory, we have the right solution for your needs.
Can I arrange servicing or calibration for my photometer?
Absolutely. We also provide servicing and calibration to keep your photometers accurate and reliable.
How quickly do you dispatch orders?
Orders placed before 2:30 pm (Monday–Friday) are dispatched the same day. We also ship on Saturdays for your convenience.
Which couriers do you use for delivery?
We deliver through UPS, DPD, and Royal Mail. You can also choose to upgrade to next-day delivery at checkout.
What is your return policy?
We accept returns within 14 days of delivery provided the items are unused, in their original packaging, and in resalable condition. Please contact our team before returning any items.
Can I place bulk or business orders?
Yes, we welcome bulk, trade, and institutional orders. For tailored pricing or large quantities, please get in touch with us directly.
How can I get help if I’m unsure which kit to buy?
You can call us at 📞 +44 (0)115888 2726 and our team will guide you in choosing the most suitable kit for your needs.