The HI1285-5 is a 3-in-1 pre-amplified multiparameter probe that measures pH, EC/TDS, and temperature within a single polypropylene body. The pH portion of this probe is constructed with a cloth junction, maintenance-free polymer gel electrolyte, and a low-temperature glass sensing bulb. The EC/TDS portion of this probe utilizes two stainless steel pins for an amperometric determination of conductivity and total dissolved solids. A built-in temperature sensor ensures that both pH and EC/TDS readings are compensated for temperature variations in both standards and samples. The design consideration for the HI1285-5 is ideal for measuring the pH, EC/TDS, and temperature in greenhouses, hydroponics, environmental monitoring, water treatment, and boilers and cooling towers. The HI1285-5 is designed for use with Hanna’s HI9813-5, HI9812-5, and HI9811-5 portable multiparameter meters.
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 HI1285-5 provides a speedy temperature reading which is then used to adjust the pH and EC/TDS results accordingly.
Polypropylene Body
The polypropylene body of the HI1285-5 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.
DIN Connector
The HI1285-5 uses a DIN connector. This type of connector is generally proprietary to the meters they are supplied with and may not be interchangeable. The HI1285-5 is designed for use with Hanna’s HI9813-5, HI9812-5, and HI9811-5 portable multiparameter meters.
| 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 | DIN |
| Applications | boilers, cooling towers, environmental monitoring, greenhouses, hydroponics, water treatment |
