Portable Conductivity/TDS/Salinity/Resistivity Meter Kit with Datalogger and USB Data Output

What the EC400S Is

The Apera EC400S (SKU AI422) is a handheld, multi-parameter water quality meter designed for accurate conductivity measurement under real-world field conditions. It measures electrical conductivity (EC), total dissolved solids (TDS), salinity, and resistivity simultaneously, converting between parameters from a single calibration in conductivity mode. The meter is built around Apera's proprietary BPB (Brush-Resistant Platinum Black) conductivity sensor — a design that minimizes electrode polarization, extends measurement range, and holds accuracy more consistently over time than standard stainless-steel electrodes.

The meter covers a wide EC range of 0 to 200 mS/cm across multiple sub-ranges (down to 0.00–19.99 µS/cm at the low end and up to 20.0–199.9 mS/cm at the high end), making it equally useful for RO or filtered source water checks and high-strength feed solutions. TDS reads out to 100 g/L; salinity to 100 ppt; resistivity to 100 MΩ·cm. Temperature is measured simultaneously with ±0.5°C accuracy across a 0 to 80°C range, and auto temperature compensation (ATC) adjusts EC readings for accuracy across varying solution temperatures.

Who This Meter Is For

Commercial cannabis and hemp cultivation teams that need a reliable, documented record of feed EC and source water quality will find the EC400S well-suited to the workflow. Environments with high humidity, wash-down areas, or general moisture exposure are squarely in scope: the IP57 dust and waterproof rating means the meter can be submerged to 1 meter for up to 30 minutes, making it durable enough for a busy fertigation room or a tissue culture lab.

For operations where compliance documentation, SOPs, or QA audits require traceable water-quality records, the onboard GLP data management is directly useful. Up to 500 measurement groups can be stored with time-stamp data, then pulled to a Windows PC via USB for logging, reporting, or integration into batch records. The meter can also be run continuously from USB power rather than batteries, useful for stationary monitoring setups at a mixing or irrigation station.

Key Features

Calibration is handled through a 1 to 4 point auto-calibration routine with automatic buffer/standard recognition. Premixed calibration solutions are included in the kit. A smart self-diagnosis function evaluates probe condition during calibration, flagging issues before they affect measurement accuracy. A calibration reminder keeps the instrument on a consistent calibration schedule — important when meters cycle between multiple staff members.

The large backlit LCD simultaneously displays EC and temperature, with on-screen icons confirming reading stability (the meter flags when a stable value has been reached, removing guesswork) and completed calibration points. A timed data-logging mode allows interval-based automatic measurement capture. The TDS conversion factor is user-adjustable from 0.40 to 1.00 (factory default 0.71) to match the ion profile of specific nutrient solutions. The BPB electrode (model 2301T-S) is a replaceable unit — probe replacement does not require purchasing a new meter body.

How It Fits a Commercial Grow Operation

In a commercial cultivation environment, EC is a daily — often multiple-times-daily — measurement. Feed EC, drain EC, reservoir EC, and source water EC all inform nutrient management decisions. The EC400S handles all of those check points in one instrument, with enough data storage to log an entire run without offloading. At end of batch or on a weekly cadence, the USB connection to a PC pulls that data out for batch records or internal QA reporting.

The IP57 housing and rubber-grip sleeve make it practical for a production floor rather than just a lab bench. The ability to power the meter through USB means it can stay stationary at a mixing station without cycling through batteries. For operations already running Apera's broader instrument lineup — pH meters, pocket testers — the EC400S fits the same ecosystem and calibration workflow, keeping staff training requirements consistent. Request a quote through HSC to confirm availability and lead time.