Product Core Brief

• Model: ZR402G-T-E-E-A
• Brand: YOKOGAWA
• Series: OpreX Analyzers
• Core Function: Processes zirconia sensor signals to calculate and output combustion oxygen concentration.
• Product Type: Single Channel Oxygen Analyzer Converter
• Key Specs: English LCD Touchscreen | HART Protocol | 4-20mA DC Dual Output
• Condition: New Original / New Surplus

Product Introduction

YOKOGAWA ZR402G-T-E-E-A converters serve as the central processing unit for in-situ zirconia oxygen probes. This industrial automation unit features an intuitive English-language LCD touchscreen for easy calibration and trend monitoring.

The YOKOGAWA ZR402G-T-E-E-A handles 0.01 to 100 vol% O2 ranges with dual 4-20mA outputs and HART digital communication. Field engineers rely on its built-in self-diagnostics to reduce maintenance costs and prevent unplanned downtime.

Key Technical Specifications

Quality Control Process

Every YOKOGAWA ZR402G-T-E-E-A undergoes a rigorous functional validation before shipping. We first verify the English LCD touchscreen responsiveness and check for dead pixels across all calibration and trend display menus. Next, technicians simulate a 4-20mA loop using precision process calibrators to ensure both output channels maintain accuracy across the 550Ω maximum load.

We also test the HART communication stack using a multi-drop simulator to verify remote configuration capabilities. The four relay contact outputs and two contact inputs are physically triggered to confirm proper fail-safe logic. Finally, the unit is sealed in anti-static packaging to protect the sensitive internal circuitry during transit.

Replacement Pitfall Guide

❗ Never ignore the load resistance limit. The YOKOGAWA ZR402G-T-E-E-A outputs max out at 550Ω. If your legacy DCS card has high impedance or long cable runs, you risk signal dropout. Always calculate total loop resistance first.

❗ Verify the fail-safe relay configuration. The unit provides four contact outputs, with one dedicated as a normally open fail-safe. Miswiring this during a retrofit can cause your DCS to ignore critical sensor faults.

❗ Check the sample gas pressure compensation. Standard probes handle up to +250 kPa, but pressures over +5 kPa require the pressure compensation option. Installing a standard converter without this option in a high-pressure stack will yield false O2 readings.

❗ Mind the HART multi-drop limits. When daisy-chaining devices, ensure your loop power supply can handle the cumulative current draw. HART communication can fail if the minimum operating voltage drops below 12V.

Keep these in mind and you’ll cut 90% of rework time.

Compatibility Matrix & Benchmarks

• Measurement Range: 0.01 to 100 vol% O2, providing wide-range flexibility for various combustion processes.
• Digital Communication: Native HART protocol enables remote troubleshooting and eliminates the need for ladder climbing.