Hanna Instruments offers a wide variety of electrodes that are designed for many different applications. The sensing material, body material, and connection type used are just some of the design considerations.
Pre-Amplified pH Electrode
The pH electrode circuit has a built-in amplifier that serves to reduce the effects of electrical noise on the high impedance pH measurement. Electrical noise can come from motors and pumps that are common in greenhouses. The single reference junction design of the pH electrode has a cloth junction that allows ion movement between the inner gel electrolyte and the sample being measured. The advantage of the cloth junction is that it can be extracted from the probe, exposing a fresh surface when readings become drifty or erratic. These features make this probe ideal for use in fertilizer solutions.
Amperometric EC/TDS Sensor
EC/TDS readings are performed by a two-pin amperometric sensor. An alternating voltage is applied to the sensor and the amount of current that passes between the two stainless steel pins determines the amount of dissolved ionic solids present.
Built-In Temperature Sensor
pH and EC/TDS readings must be temperature compensated in order to obtain accurate results. The built-in temperature sensor of the HI1285-7 provides a speedy temperature reading which is then used to adjust the pH and EC/TDS results accordingly.
The polypropylene body of the HI1285-7 houses all three sensors within a sturdy, single body design. This body material is suitable for a wide range of applications and excels in measurements with portable meters due to its durability. The fins around the spherical glass pH bulb minimizes breakage due to accidental bumping or dropping of the electrode. The polypropylene plastic is a high-quality plastic that is chemically resistant to many aggressive chemicals.
Quick Connect DIN Connector
The HI1285-7 uses a Quick Connect DIN connector that makes attaching and removing the probe simple and easy. This type of connector is generally proprietary to the meters they are supplied with. The HI1285-7 is designed for use with Hanna’s HI9814 GroLine hydroponic waterproof pH/EC/TDS/Temperature portable meter.
Body Material polypropylene Reference single, Ag/AgCl Junction / Flow Rate cloth Electrolyte gel Range pH: 0 to 13, EC Max Pressure 0.1 bar Tip Shape spheric (8 mm) Diameter 16 mm Body Length / Overall Length 95 mm / 185 mm Recommended Operating Temperature 0 to 50°C (32 to 122°F) - LT Temperature Sensor yes Matching Pin no Amplifier yes Digital no Cable 7-pole; 1 m (3.3') Connection Quick connect DIN Applications agriculture, greenhouses, hydroponics Warranty 6 months