Yokogawa PH402G-E-1-E pH/ORP Analyzer Transmitter

The Yokogawa PH402G-E-1-E EXA pH/ORP Analyzer Transmitter is an online dual-input pH and ORP analyzer that converts high-impedance sensor signals into standardized process outputs for continuous liquid monitoring in industrial environments. Commonly used in chemical plants, water treatment facilities, wastewater treatment, food and beverage production, and power generation systems, it provides real-time measurement, alarm handling, and control outputs for dosing or neutralization with built-in PI control for accurate mA and relay-based control. Key specifications include pH measurement from -2 to 16 and ORP from -1500 to +1500 mV; dual sensor inputs (≥10¹³ Ω), dual isolated 4–20 mA outputs plus relay outputs, RS-485 digital communication, and an LCD with diagnostic and calibration interface. Power is 100–240 VAC at 50/60 Hz with about 10 VA consumption, and the enclosure is IP65 / NEMA 4X, suitable for panel, wall, or pipe mounting. This is a discontinued legacy model, with common replacements such as the Yokogawa FLXA21 and FLXA202 pH analyzers or the PH450G Converter.