Yokogawa ZR22G Zirconia Oxygen/Humidity Analyzer

• No complex gas sampling system required; insert probe directly into duct/furnace to measure hot flue gas continuously.
• Solid zirconia cell sensing principle, supports dual measurement modes: oxygen concentration & high-temperature vapor humidity.
• Ultra-fast response: 90% value reached within 5 seconds, ideal for real-time combustion closed-loop controlYokogawa E....
• Wide measuring range:
  • O₂: 0.01 ~ 100 vol%
  • H₂O vapor: 0 ~ 100 vol%
  • Mix ratio: 0 ~ 1.000 kg/kgYokogawa E...

• Standard probe: 0 ~ 700°C process gas
• Optional high-temperature adapter ZR22P: extend measuring range up to 1800°C (SiC tube option for extreme high temp)web-materi...

• Standard range: -5 ~ +20 kPa
• Optional pressure compensation module for -0.725 ~ +36.3 psi fluctuating furnace pressureweb-materi...

• Probe ambient working temp: -20 ~ +150°C
• Wetted materials: SUS316 stainless steel, zirconia ceramic core
• Multiple insertion lengths available: 0.15m / 0.4m / 0.7m / 1.0m up to 5.4m, customizable flange connections
• Three reference air supply modes: natural convection, instrument dry air, pressure compensated air supplyweb-materi...

• Oxygen accuracy: ±3% FS for 0–25 vol% O₂; ±5% FS for 0–100 vol% O₂
• Humidity accuracy: ±2 vol% H₂O under stable pressure; ±3 vol% under ±2 kPa fluctuation
• Low drift: Zero & span drift ≤ ±2% FS per month for oxygen
• Repeatability ≤ ±0.5% FS for low oxygen range (0–5 vol%)Yokogawa E...
• Built-in heating module stabilizes zirconia cell temperature automatically, eliminates cold-start measuring deviation (20-min warm-up time)Yokogawa E...

• Detachable zirconia sensor cell + heater assembly: replaceable on-site without removing full probe from pipeline, greatly cut downtime and maintenance costYokogawa E...
• Optional blowback tee structure to clear dust, ash and tar accumulation on probe tip, extend service life in dusty flue gas
• Front accessible calibration gas inlet for zero/span gas calibration without disassembly
• Rotatable flange housing, flexible installation orientation for narrow industrial spaces

When paired with ZR402G/ZR802G converter, complete signal output options:

• Dual isolated 4–20mA analog outputs (max load 550Ω)
• Digital communication protocols: HART 7, RS485 Modbus RTU, Ethernet Modbus TCP
• Multi-channel relay contacts: configurable for high/low O₂ alarm, maintenance alert, calibration status, blowback trigger, fault diagnosis signalweb-materi...

Continuous real-time monitoring of probe health status:

1. Zirconia cell impedance aging & degradation warning
2. Heater abnormal temperature detection
3. Reference air supply pressure shortage alarm
4. Probe surface fouling/ash blockage early reminder
5. Full fault log stored in converter for traceable troubleshooting

• Predictive maintenance reminder reduces unnecessary offline inspection frequencyYokogawa E...

• Standard ZR22G: general industrial IP66 protection
• Explosion-proof variant ZR22S available, certified ATEX, FM, CSA, IECEx for Class I Div 1 hazardous combustion zones
• Compliant with IEC61010 safety standard, RoHS certified

1. Power plant boiler, waste incinerator flue gas oxygen control for energy saving & NOx reduction
2. Steel, ceramic, kiln low-oxygen firing atmosphere monitoring
3. Petrochemical furnace, heating furnace combustion optimization
4. Pulp & paper, food, textile high-temperature drying oven humidity control
5. Industrial thermal treatment, heat treatment furnace atmosphere detection

1. Sampling system eliminated: no cooler, filter, pump & regular sampling pipeline maintenance
2. Modular replaceable sensor reduces spare parts cost
3. Blowback accessory prolongs probe service life in dusty gas
4. Precise oxygen control improves combustion efficiency, cuts fuel consumption and lowers exhaust pollutant emissions