The HI2550 is a rugged and highly accurate multiparameter benchtop meter that measures pH/ORP/ISE, EC/TDS/Salinity, and temperature with a clear LCD display, data logging capability, and USB port for computer connectivity.

The HI2550 is a dual channel meter that allows for measurement of pH, ORP, and ISE on one channel and EC, TDS, and salinity, on the other. Readings for pH and EC can be manually or automatically compensated for temperature variations with the separate HI7662 temperature probe or from the built-in temperature sensor of the conductivity probe on channel two.

As a pH meter, the HI2550 can be calibrated up to five points with a choice of seven standard buffers or two custom buffers. As an EC/TDS/Salinity meter, the HI2550 can be calibrated at one point for offset and at one point for slope with a choice of six conductivity standards. The % NaCl is calibrated to a single point at 100% with the optional HI7037 salinity standard. The calibration data including date, time, standards used, offset, slope, cell constant, and cell factor can be accessed at any time by pressing the dedicated GLP button.

Features at-a-glance

HI1131B pH Electrode - The HI2550 is supplied with the HI1131B glass body, double junction, refillable pH electrode with an indicating sensor made of High Temperature (HT) glass. The double junction and HT glass design allows the HI1131B to be used in a wide variety of application from samples with metals and Tris buffer to samples at elevated temperatures.

HI76310 Conductivity Probe - The HI76310 platinum, four-ring probe measures EC, TDS, and salinity. The probe features a built-in temperature sensor and operates over a wide range from 0.00 μS/cm to 500.0 mS/cm (actual conductivity), 0.00 to 400.0 g/L (actual TDS), and 0.0 to 400.0% NaCl.

Temperature Compensation - Temperature measurements for pH and EC can be compensated for automatically (ATC) or manually (MTC) from -20.0 to 120.0°C, or compensation can be disabled for actual conductivity or TDS measurements. The temperature correction coefficient for EC or TDS, also referred to as β, is adjustable from 0.00 to 6.00 %/°C.

Automatic Calibration – The pH channel offers up to five-point pH calibration with seven standard buffers and up to two custom buffers. EC and TDS are automatically calibrated at one point with a choice of six pre-programmed standards. Salinity is calibrated at one point using the HI7037 100% NaCl standard solution.

Autoranging - In the EC and TDS measurement modes, the HI2550 automatically chooses the optimum measurement scale based on the sample solution to maintain the highest possible accuracy.

Adjustable TDS Factor - The factor that relates conductivity to total dissolved solids is based on the type of sample being measured. For users to get an accurate determination of TDS based on their unique solution, the TDS factor is adjustable from 0.40 to 0.80.

GLP Data – The calibration data including date, time, standards used, offset, slope, cell constant, and cell factor can be accessed at any time by pressing the dedicated GLP button.

Data Logging –  The log-on-demand feature allows up to 200 data points to be recorded. Up to 500 data points can be recorded when utilizing interval logging, which allows the user to specify time intervals from 5 seconds to 180 minutes.

Data Transfer – With a built-in logging function, measurements are stored in non-volatile memory, and can be transferred to a PC through the USB port using the optional HI92000 software and HI920013 USB cable (both sold separately).