When voltage is applied to a zirconia electrolyte cell, oxygen is pumped through the zirconia disc from the cathode side to the anode side because the carriers of the current flowing through the zirconia electrolyte are oxygen ions. By attaching a cap with a pinhole on the cathode side of the cell and by increasing the voltage over the cell the current shows saturation due to the rate limiting step in the transfer of oxygen to the cathode. This saturation current is called limiting current and is nearly proportional to the ambient oxygen concentration.
Warm up time: Min. 30 s
Maximum permissible operating temperature: 350 °C (*)
*Depending on the cable and filter assembly (see paragraph: specification, Cable assembly)
Permissible volumetric flow rate (Purging the sensor)
For all sensor types, the maximum flow rate depends on the way of purging the sensor (sensor in direct gas flow, gas beam shape, etc.) and the size of the measuring chamber. Exception: SO-E1-xxx
(TO8 + hose connection for direct gassing). Permissible flow
[ml/min]: 100 - 500 (optimal: 250)
Lifetime (MTTF): ~ 20.000 hours (*)
* Depending on measuring medium. Stated lifetime refers to a heated, operated sensor of type SO-xx-250 and SO-xx-960. A failure or reaching the lifetime typically means a slight deviation
from the dispatch specifications.
Vibration resistance
Sensors based on the TO8 socket as well as those built with a TO39 socket (SO-Bx-xxx, SO-Ex-xxx, SO-Ax-xxx) meet the European Norm EN60068-2-6 (Sinusoidal vibration tests).
SO-E2-960 Limiting Current Type Zirconia Oxygen Sensors operational principle When voltage is applied to a zirconia electrolyte cell, oxygen is pumped through the zirconia disc from the cathode side to the anode side because the carriers of the current flowing through the ...
SO-E2-960 Limiting Current Type Sensor Oxygen sensors When voltage is applied to a zirconia electrolyte cell, oxygen is pumped through the zirconia disc from the cathode side to the anode side because the carriers of the current flowing through the zirconia electrolyte are ...