WE420 Sodium Analyzer

The WE420 Sodium Analyzer is an online continuous analyzer that uses an ion selective electrode and reference electrode to measure the sodium concentration. Sodium measurement can be used to monitor and control online water and steam quality. The measurement results serve as a good indicator of condensate leakage and possible turbine corrosion. With turbine corrosion repairs costing up to $30 billion a year, sodium monitoring ultimately reduces the costs to generate, transmit, and distribute electricity.

The WE420 is ideal for power generation water applications such as feedwater, boiler water, deaerator inlet/outlet, condensate discharge, and economizer inlet.

Why measure sodium?

About OpreX

OpreX is the comprehensive brand for Yokogawa’s industrial automation (IA) and control business and stands for excellence in the related technology and solutions. It consists of categories and families under each category. This product belongs to the OpreX Analyzers family that is aligned under the OpreX Measurement category.



Process Guard

Calibration utilizes the online process sample with Double Known Addition for low range standards, ensuring the most accurate calibration and online measurement readings.

Expert Guide

WE420 Sodium AnalyzerThe WE420 is extremely easy to use and maximizes uptime. It features simple step-by-step scrolling instructions for setup including calibration, operation, and diagnostics menus.

View measurements at a glance from any distance in even the lowest light conditions using the large operator friendly backlit display.

Reduced Maintenance

The WE420 minimizes operator time and maintenance without the use of complicated moving parts or pumps, which often require frequent attention and expensive spare part expenditures. The low level of reagents that the WE420 uses extends reagent consumption for up to three months.

Unlike other units on the market that require thorough soaking time in high levels of sodium followed by pure water rinsing, the ion selective sensor used in the WE420 only requires quick etching in a low dilution sample of hydrofluoric acid (HF) that is less concentrated than what is in a prescription toothpaste.

Advanced Flexibility

With the WE420, users have the ability to select from three different reagents to meet the needs of the applications and environmental compliance.

Why measure sodium?

Sodium is always present with chlorides, sulfates, and hydroxide, all of which are highly corrosive. At high pressures and high temperatures, sodium is readily soluble in steam, which can cause stress corrosion cracking of superheater tubes and may lead to deposits on turbines.

Sodium ions are the first to slip off in any reaction, quickly detecting exhaustion and leakages. This is especially important in condenser cooling water, where leakage detection can prevent contamination of boiler water.

Giving You More Insight




Yokogawa's Wet Chemistry analyzers are used for measurement of Sodium, Silica, Hydrazine, and Phosphate, and are suitable for keeping water quality at an optimal level for steam generation.