YOKOGAWA OX100 - Sensor Operating Principles

<1. Overview>
1-6
IM 11M10A01-01E
Standard
Gas
OX100 Sensor
K9424JD
(255)
(310)
(90)
∅75
Pressure
Gauge
Gas Vent Tubing
Needle Valve Assembly
Needle Valve Assembly, with Pressure Reducing Valve
and Fixed Throttle
Rc1/8 (Nominal diameter of piping
connection for K9424JD)
Standard Gas Cylinder
Standard Calibration
Gas (6 bottles/box)
K9424JC
Approx. 340
Approx. 180
Part Number Specications
K9424GA Sampling unit
K9424JA Calibrationkit:1000ppm,6cylinders(1L)+needlevalveassembly,withowadjustment
K9424JB Calibrationkit:1000ppm,6cylinders(1L)+needlevalveassembly,withoutowadjustment
K9424JR Calibrationkit:10000ppm,6cylinders(1L)+needlevalveassembly,withowadjustment
K9424JS Calibrationkit:10000ppm,6cylinders(1L)+needlevalveassembly,withoutowadjustment
Figure1.4 CalibrationKit(Optional)
1.5 SensorOperatingPrinciples
Pt leadwire
Pt leadwire
Pt leadwire
Anode
Cathode
Perforated alumina substrate
Pt heater
(heated to 700°C)
Fixed Electrode
(Zirconia)
CurrentowingintheZirconiaxedelectrolytecausesoxygentomovefromthenegativeto
positiveelectrode(actsasanoxygenpump).Iftheowofoxygentothenegativeelectrodeis
restricted by the alumina substrate then a current saturation area is created and the same current
owsregardlessoftheappliedvoltage.Thecurrentthatowsiscalledthelimitingcurrent.When
axedvoltageisapplied,thecurrentowisproportionaltotheoxygenconcentration.
4th Edition : Oct. 23, 2019-00